WO2002103811A1 - Appareil semi-conducteur d'emission de lumiere - Google Patents

Appareil semi-conducteur d'emission de lumiere Download PDF

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Publication number
WO2002103811A1
WO2002103811A1 PCT/JP2001/005097 JP0105097W WO02103811A1 WO 2002103811 A1 WO2002103811 A1 WO 2002103811A1 JP 0105097 W JP0105097 W JP 0105097W WO 02103811 A1 WO02103811 A1 WO 02103811A1
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Prior art keywords
layer
nitride semiconductor
conductivity type
electrode
emitting device
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PCT/JP2001/005097
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English (en)
Japanese (ja)
Inventor
Shinichi Nagahama
Tomoya Yanamoto
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Nichia Corp
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Nichia Corp
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Priority to PCT/JP2001/005097 priority Critical patent/WO2002103811A1/fr
Priority to TW091113100A priority patent/TW558846B/zh
Priority to PCT/JP2002/005998 priority patent/WO2002103813A1/fr
Priority to JP2003506019A priority patent/JP3956941B2/ja
Publication of WO2002103811A1 publication Critical patent/WO2002103811A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/80—Constructional details
    • H10H20/83—Electrodes
    • H10H20/832—Electrodes characterised by their material
    • H10H20/833—Transparent materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/80—Constructional details
    • H10H20/81—Bodies
    • H10H20/816—Bodies having carrier transport control structures, e.g. highly-doped semiconductor layers or current-blocking structures
    • H10H20/8162—Current-blocking structures
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/80—Constructional details
    • H10H20/81—Bodies
    • H10H20/822—Materials of the light-emitting regions
    • H10H20/824—Materials of the light-emitting regions comprising only Group III-V materials, e.g. GaP
    • H10H20/825—Materials of the light-emitting regions comprising only Group III-V materials, e.g. GaP containing nitrogen, e.g. GaN
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/80—Constructional details
    • H10H20/83—Electrodes
    • H10H20/831—Electrodes characterised by their shape
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
    • H10W72/00—Interconnections or connectors in packages
    • H10W72/90—Bond pads, in general
    • H10W72/921—Structures or relative sizes of bond pads
    • H10W72/926—Multiple bond pads having different sizes

Definitions

  • the present invention relates to a light emitting device using a nitride semiconductor, and in particular, relates to G a NA 1 N or In n N, or a III-V group nitride semiconductor (I nbA G a N 0 ⁇ b, 0 ⁇ db + d ⁇ 1), light-emitting device, floodlight, collective lamp, illumination, optical coupling device, photodetection device, optical communication device, optical fiber
  • the present invention relates to a light-emitting element used as a light source of a light emitting device.
  • nitride semiconductor lasers for use in optical disk systems, such as DVDs, capable of recording and reproducing high-capacity, high-density information.
  • semiconductor laser devices using nitride semiconductors have been actively studied.
  • light-emitting elements and laser elements using nitride semiconductors can emit light in a wide wavelength range and visible light range from ultraviolet to red, so their application range is the light source of the optical disk system described above. Not only that, but it is also expected to be a wide variety of light sources, such as laser printers, optical network light sources, full color display light sources, and signal light sources.
  • surface-emitting light-emitting elements have been realized using many semiconductor materials, such as being capable of optical integration, a light source with a small spot, and an array light source in which a plurality of light sources are arranged.
  • semiconductor materials such as being capable of optical integration, a light source with a small spot, and an array light source in which a plurality of light sources are arranged.
  • a light-shielding film having an opening corresponding to the shape of the light source, and an end surface and a side surface of the device using a reflective film.
  • a structure that covers the back and the like is used. In this case, in addition to the light emitted from the opening, light reflected inside the element by the reflective film is generated, and a loss due to the light is generated. Therefore, only light with low light extraction efficiency can be obtained.
  • a structure is used to increase the luminous efficiency by forming a transparent overall electrode and expanding the current flow in the p-type layer, but on the other hand, loss occurs due to light absorption by the translucent electrode, It was difficult to increase the light extraction efficiency. In this way, even if the P electrode is provided on the entire surface, the current tends to flow unevenly in the structure in which a pair of positive and negative electrodes are provided on the same surface, and the directivity of light emitted to the outside of the device is anisotropic.
  • the intensity of the light from the end face of the active layer is higher than the light from the upper surface of the p-type layer surface, and the directional element emits light of higher intensity to the upper surface of the p-type layer.
  • Light-emitting elements with such a biased directivity require a special design for external reflectors and optical lenses, such as LED lamps, to provide a light source with the desired directivity in the application. This hindered the application of semiconductor light emitting devices.
  • FIGS. 7B to 7D a structure in which a pair of positive and negative electrodes are arranged on the same surface side of a substrate is used for a rectangular, square, rhomboid, or parallelogram element. Attempts have been made to prevent current localization by disposing them at a diagonal line or at the center of or near a pair of opposing sides and increasing the distance between the p and n electrodes to separate them. It has been. However, in any case, when the cross section is cut by a straight line connecting the positive and negative electrodes in FIGS.
  • the cross section has the structure shown in FIG. 7A, and the current is localized in a region near the n electrode. This is because, as is clear from FIG. 7A, the current spreads in the inward direction of the pn junction between the p-type layer and the entire surface of the electrode (light-transmitting). This is because the flow of the current in the in-plane direction is prioritized. That is, in the cross section shown in Fig. 7A, the current flow in the lateral direction (in the direction of the pn junction plane) is given priority in the electrode with lower resistance than in the p-type layer, and most of the current flows in the lateral direction in the whole electrode.
  • the path X that flows in the vertical direction (thickness direction) through the P-type layer, active layer, and n-type layer near the n-electrode Path for example, a path Z that flows vertically in the region directly below the extraction electrode of p and flows horizontally in the n-type layer, a p-side electrode, and a path Y that flows horizontally in the n-type layer.
  • n-electrode on the n-type layer surface is In the cross section of Fig. 7A, the n-electrodes are arranged on both the left and right sides of the active layer, or the p-extraction electrodes are extended to two planes intersecting the active layer end faces. Attempts have been made to spread the word.
  • the current in the active layer surface has a higher priority in the vicinity of the end surface of the active layer near the n-electrode than in the region away from the end surface of the active layer, the center, and the like. Since there is no change in the flowing structure, the intensity of light from near the edge of the active layer is higher than that from the surface of the p-type layer, and the directivity in the active layer is improved. Light is not extracted upward from the surface of the mold layer, so that is not improved.
  • DISCLOSURE OF THE INVENTION According to the present invention, it is possible to obtain a light-emitting element with improved light extraction efficiency from the element structure forming surface side of a substrate, which has been conventionally difficult.
  • the laminated structure of the nitride semiconductor light-emitting device of the present invention is a device obtained by laminating a nitride semiconductor layer on a substrate 1. 11, a second conductivity type layer 12, and an active layer 3 between them.
  • This is a light emitting device having a constriction layer 5 and a window 40 or a light-transmitting film 30 and an electrode 20 partially formed on the second conductivity type layer 12.
  • a third nitride layer having an opening 41 between at least the first nitride semiconductor layer 4 and the second nitride semiconductor layer 6 thereon is provided in the second conductivity type layer.
  • the third nitride semiconductor layer 5 may be a layer of the first conductivity type different from the second conductivity type, that is, an inversion layer, and is a high-resistance i-type layer or an anti-insulating layer.
  • the light emitting element of the present invention has a structure in which an electrode on the second conductivity type layer or a window for light extraction is provided to facilitate light extraction upward and in the stacking direction.
  • An element structure with a current confinement layer that restricts the current path in the conductivity type layer and disperses the current in the plane by providing an opening to increase the light extraction efficiency from the top surface It will be.
  • the upper p-type layer in many cases cannot have a high carrier concentration, and the current due to the p + -type high carrier concentration layer is low.
  • the current path in the plane is limited to the opening, and the openings are distributed in a plurality of planes, so that the current path is large and wide in the plane.
  • the structure is distributed and dispersed to increase luminous efficiency.
  • the first conductivity type layer may include a substrate, that is, may have a structure using a first conductivity type substrate.
  • the current confinement structure allows light from the active layer immediately below the opening to be efficiently extracted from the window located above.
  • a translucent electrode having a large sheet resistance reduces the suppression of current spreading in the plane, and enables efficient extraction of surface-emitting light by using it in combination with a current confinement layer.
  • the window portion is an electrode, particularly a first electrode 20 for ohmic contact, on the surface of the second conductivity type layer. Is provided partially, so that the region where no electrode is provided becomes a window.
  • the translucent film may be formed only on a part of the window part, and is preferably formed on almost the entire surface of the window part because light can be efficiently extracted upward from the entire surface of the window part.
  • the translucent film covers a part of the electrode of the second conductivity type layer, in particular, a part of the first electrode for the ohmic contact, and can form a light extraction structure even if it is formed thereon. There is no problem, and when the first electrode is a light-transmitting electrode, a structure can be obtained in which light transmitted through the light-transmitting electrode can be efficiently extracted to the outside via the light-transmitting film.
  • the reflection layer when the reflection layer is formed on the substrate surface on which the second conductivity type layer is laminated or on the substrate surface opposite thereto, light is propagated in a direction perpendicular to the substrate surface. It can be efficiently expressed, and in particular, can have a structure that guides light to the surface of the second conductivity type layer provided with the window.
  • a reflective layer is formed between the active layer and the substrate, in particular, a semiconductor multilayer film in which layers having different compositions or refractive indices made of a nitride semiconductor are alternately or periodically laminated is formed so as to be close to the active layer.
  • the reflection layer can be arranged in such a manner that the light can be emitted to the upper surface.
  • the first electrode 20 for ohmic contact provided on the surface of the second conductivity type layer is a translucent electrode
  • the first electrode 20 is electrically connected to the first electrode.
  • a second electrode 22 connected to the first electrode 22 is provided as shown in FIG. 3, and the second electrode 22 is spread over the surface of the first electrode 20 as shown in FIGS. 12B and 12C.
  • the current is spread in the plane by the second electrode 22 having a small sheet resistance, while the light propagating upward from within the element structure is formed by the first electrode 20 having a light-transmitting property.
  • the first electrode 20 is opened not only in the window but also in a form in which the first electrode 20 is opened, a structure capable of extracting light upward can be obtained, and a light-emitting element with improved light extraction efficiency and in-plane diffusion of current can be obtained.
  • the light emitting device of the present invention can have a structure in which a current path is selectively provided in the opening.
  • a structure can be achieved in which photoelectric conversion is efficiently performed in the active layer, improving luminous efficiency it can.
  • windows corresponding to the plurality of openings in-plane A structure can be obtained in which light propagating upward from the dispersed openings can be efficiently extracted to the outside.
  • the light emitting device of the present invention described above is applicable to a self-standing type light emitting device in which a pair of positive and negative electrodes are opposed to each other across a substrate, and a so-called flip chip type in which a pair of positive and negative electrodes are disposed on the same surface side of the substrate. Is what is done. Further, in a light emitting element in which a pair of positive and negative electrodes are arranged on the same surface side of a substrate, an exposed surface 2 s that exposes a part of the first conductivity type layer that is to be one of the electrode forming surfaces is formed so that the exposed surface is formed.
  • an electrode of the first conductive type layer is formed. 21 is formed so as to surround the convex portion or along the side surface of the convex portion, so that the current path can be spread in the plane of the convex portion, and the luminous efficiency and light extraction efficiency can be improved. An improved light emitting element structure can be obtained.
  • the electrode may have a shape that is closed so as to surround the entire side surface of the projection, or may have an electrode shape that partially surrounds the projection.
  • the current constriction layer surrounds the side surface of the convex portion, that is, the current is applied to the side surface of the convex portion.
  • the current confinement layer 5 is provided on the side surface of the convex portion 51 so that the side surface of the current confinement layer surrounds the side surface of the convex portion. It is formed in When almost the entire side surface of such a convex portion is formed so as to be surrounded by the current confinement layer, the current flow near the side surface of the convex portion is reduced by current constriction corresponding to the electrode 21 formed so as to surround the convex portion. It can be limited by providing a layer.
  • a light-emitting element having a structure in which the opening of the current constriction layer is formed so as to open on at least a part of the side surface of the projection may be used.
  • the opening is arranged on the side surface of the convex portion 51 without providing the current constriction layer.
  • an opening portion 41 where the side surface of the current confinement layer 5 partially opens is formed. It becomes a broken structure.
  • the current flows through the opening portion that opens on the side surface of the convex portion, so
  • the active layer which is the light-emitting layer located at the point
  • a large amount of light can be extracted from the side surface of the convex portion near the light-emitting point.
  • a light-emitting element that achieves light extraction not only from above but also from the side can be realized, and light extraction efficiency can be improved.
  • a current confinement layer that is partially opened, but not entirely, on the side surface of the convex as shown in FIG.
  • a large amount of current is also distributed within the internal surface, and current concentration on the side of the convex portion, which is a short circuit between a pair of positive and negative electrodes, especially during large current operation, resulting in light emission from the side Prevents concentration and enables efficient light extraction from the top surface That.
  • FIG. 17 is a schematic perspective view (FIG. 17A) showing a light emitting element chip according to an embodiment of the present invention, and a schematic oblique view showing the current confinement layer 5 in FIG. 17A.
  • Figure 17B A thick line 23a in FIG. 17B and a hatched region 22a in the figure respectively represent a third electrode (first electrode) and a second electrode 22 with a current confinement layer.
  • 5 Image projected on the surface. 5A and 5B show a part of the side surface of the convex portion facing the electrode of the first conductivity type layer, particularly the bonding electrode 24 in FIG. 17A.
  • the side surface not facing the electrode 24, for example, 5c indicates that the opening 41 is open on the side surface.
  • FIG. 17A shows a schematic perspective view showing a light emitting element chip according to an embodiment of the present invention
  • Figure 17B shows a schematic oblique view showing the current confinement layer 5 in FIG. 17A.
  • Figure 17B A thick line 23a in FIG. 17B
  • FIG. 18 is a schematic perspective view (FIG. 18B, D) of a part of the light emitting element chip (FIG. 18A, C) and the current confinement layer 5 extracted similarly to FIG.
  • FIGS. 18A and 18B and FIGS. 18C and 18D are different embodiments, both of which show a part of the convex region 51, particularly near the end, for example, in the longitudinal direction.
  • Figure 12 shows the vicinity of the end of the convex portion having the shape or the stripe-shaped convex portion. In the above description, the vicinity of an end of a stripe-shaped convex portion forming a part of the convex portion will be described. Further, hatched regions 23a and 30a in FIGS.
  • the notched area 22 a is an image in which the bonding electrode is projected on the pn junction surface.
  • the opening 41 should not be provided immediately below the bonding electrode 22, that is, the image of the electrode 22 should not overlap the image of the opening on the pn junction surface.
  • the electrode 23 is formed in a region other than the region 30a (40a).
  • the light emitting device of the present invention is particularly suitable for the case where the first conductivity type layer has higher electric resistance than the second conductivity type layer, that is, the carrier concentration of the second conductivity type layer is higher than that of the first conductivity type layer.
  • the first conductivity type layer is an n-type nitride semiconductor layer
  • the second conductivity type layer is a p-type nitride semiconductor layer, which corresponds to the above condition.
  • the electrodes of the first conductivity type layer are provided so as to surround the corners or corners where the side surfaces intersect.
  • current tends to be locally injected into the corners and corners, but in the present invention, by providing a current constriction layer at the corners and corners, current concentration is prevented, and a plurality of currents are prevented.
  • a high luminous efficiency can be realized by making it possible to have a structure in which the current is spread by dispersing it in the opening, and a device structure in which the local concentration of the current is eliminated. Specifically, as shown in FIGS.
  • the current confinement layer 5 is provided at the corner or corner where the side surfaces of the convex portion 51 intersect, so that the current path at this location is eliminated.
  • the current can be distributed to the openings.
  • the corners where the convex side surfaces intersect are as shown in Figs. 17 and 18.
  • the corner where the chamfered, rounded, or rounded portion is formed in the area where the side surfaces of the convex portion 51 intersect.
  • the tendency of current concentration tends to be reduced more than this, but by providing a current confinement layer also at this corner, the current path can be distributed to other openings arranged in the plane.
  • the shape of the openings is smaller than that of the structure having the corners.
  • the current path is formed by the electrodes for each of the openings that have been received by forming them so that they do not overlap and surround the periphery ( Figure 19A, Figure 19B). Structure.
  • the area and width of the opening are large, a large amount of current flows through the periphery of the opening, and a region where the current density is sparse at the center of the opening is created. At times, the tendency for short-circuiting increases, and this tendency becomes greater, and a situation arises in which the current confinement layer, which functions as an in-plane spread of current, does not function well.
  • the electrodes 20 are arranged so as to partially overlap the openings in the projected image of the pn junction surface. Current can be prevented from becoming sparse and uniform current spreading can be achieved in the opening area. Preferably, one opening is divided into a plurality of areas as shown in the figure. In addition, by forming the electrodes 20 so as to crosslink, it is possible to improve the form in which such current paths are sparse. At this time, the first electrode is the first electrode for ohmic contact, but is realized by the current being widely diffused in the plane.
  • the electrode is formed with a sufficient film thickness and is formed as an opaque film having a low transmittance, that is, the first electrode for ohmic contact and the second electrode 2 for current diffusion. 3, and its shape and pattern can be a lattice shape or the like for the purpose of current diffusion described later, similarly to the second electrode.
  • the first electrode 20 is transparent
  • FIGS. 19A and 19B show the electrode arrangement or shape and the aperture, using an image obtained by projecting the opening 41 a and the first electrode or the third electrode 23 a onto the pn junction surface 50. It explains the relationship between the arrangement and the shape, and particularly, how the two are close to each other, or how the electrodes are provided along the opening, and how the electrodes partially overlap or bridge the opening.
  • a first electrode 20 is provided along the longitudinal direction, preferably substantially parallel to the longitudinal direction, so that the periphery of the opening is A structure in which electrodes are arranged along the long side allows the current to be distributed in the opening in the longitudinal direction and to operate with an appropriate distribution.Efficient current diffusion without increasing the resistance of the element Can be realized.
  • a first electrode 20 substantially parallel to the longitudinal direction is formed along an opening 41 having a longitudinal direction, at least a part thereof. It is formed as an electrode substantially parallel to the longitudinal direction.
  • the longitudinal direction of the opening and the electrode, or a part thereof is provided along or substantially parallel to the longitudinal direction, also holds between the electrode 21 of the first conductivity type layer. It is. Specifically, as shown in FIG. 18, at least a part of the electrode 21 extends in the longitudinal direction or the stripe direction along or almost parallel to the longitudinal direction of the opening 41 or the stripe direction. That is, the shape to be provided. At this time, at least a part of the convex region 51 has a longitudinal direction and a stripe direction, and by disposing the longitudinal direction of the opening substantially parallel to the direction, the electrode 21 of the first conductivity type layer is formed. Is preferable because it can be easily arranged along the opening.
  • a current confinement layer is provided on the side of the convex portion facing the bonding electrode of the first conductivity type layer so as to surround the same. That is, it is preferable to provide a current confinement layer that is opened on at least a part of one side surface on the other side surface of the convex portion without providing an opening portion that is opened on the side surface, since good light extraction from the side surface is realized. This is because, as shown in FIG. 17, since the bonding electrode 24 has a ball formed at the time of wire connection, the bonding electrode 24 has a ball warp (approximately 50 / im to 100) to provide the bonding surface.
  • the active layer 3 which is the light-emitting layer because it tends to be formed with a thick film to obtain durability in device operation.
  • the current confining layer is formed so as to surround the entire surface of the convex portion, thereby preventing the side emission from being shielded by the electrode 24, while the other convex portion is formed.
  • On the side surface by providing an opening that partially opens on the side surface of the protrusion as described above, a structure can be obtained in which light emitted from the side surface is efficiently extracted to the outside.
  • the convex side surface facing the electrode 24 is a straight line arbitrarily connecting the electrode 24 or its side surface and the convex side surface, and the straight line does not pass through, intersect, or cross the convex region.
  • This corresponds to the convex side surface that is connected without being connected, and when the convex side surface has a curved surface, a part of the continuous side surface may correspond to the convex side surface facing the electrode.
  • the present invention can be applied to the case where the side surface of the convex portion is a curved surface.
  • the third nitride semiconductor layer, A 1 of the quaternary mixed crystal I n y G a x - y N (0 ⁇ ⁇ 1, 0 ⁇ y ⁇ l, x + y ⁇ 1) is preferable because it can function as a good current confinement layer.
  • the third nitride semiconductor of quaternary mixed crystal A 1 InGaN is an AND layer, for example, as compared with the case where the third conductivity type is doped with impurities of the first conductivity type.
  • the current constriction layer can be formed with good crystallinity.
  • the resistance is increased due to the deterioration in crystallinity. It is preferable because a p-type layer can be formed with good crystallinity.
  • the first nitride semiconductor layer (lower layer) and the second nitride semiconductor layer (upper layer) sandwiching the third nitride semiconductor layer are formed more than the quaternary mixed crystal third nitride semiconductor layer.
  • a nitride semiconductor having a small number of group III and III constituent elements By using a nitride semiconductor having a small number of group III and III constituent elements, a favorable crystalline laminate can be realized. Specifically, a nitride semiconductor composed of a compound of N and at least one or two of the Group III elements selected from the group consisting of In, Ga, and A 1 Good crystallinity can be realized. BRIEF DESCRIPTION OF THE FIGURES
  • FIG. 1 is a schematic sectional view illustrating an element structure according to an embodiment of the present invention.
  • FIG. 2 is a schematic sectional view illustrating an element structure according to one embodiment of the present invention.
  • FIG. 3 is a schematic sectional view showing an element structure according to an embodiment of the present invention.
  • FIG. 4 is a schematic cross-sectional view illustrating a lamination process of the current confinement structure according to the embodiment of the present invention.
  • FIG. 5 is a schematic sectional view illustrating an embodiment of the present invention.
  • FIG. 6 is a schematic cross-sectional view illustrating a method for growing a lateral growth layer according to one embodiment of the present invention.
  • FIG. 7 is a top view (plan view) showing an electrode arrangement of a conventional light-emitting element, and a schematic cross-sectional view for explaining the element structure.
  • FIG. 8 is a top view illustrating an embodiment of the present invention, and a schematic cross-sectional view taken along the line AA.
  • FIG. 9 is a schematic cross-sectional view illustrating an embodiment of a light emitting device using the light emitting element of the present invention.
  • FIG. 10 is a schematic cross-sectional view illustrating an element structure according to an embodiment of the present invention and a sealing mode using a sealing member.
  • FIG. 11 is a schematic diagram illustrating an arrangement relationship between an opening and a window according to the present invention on a pn junction surface 50.
  • FIG. 12 is a schematic top view illustrating an electrode arrangement and the like according to an embodiment of the present invention.
  • FIG. 13 is a schematic perspective view illustrating an embodiment of the present invention.
  • FIG. 14 is a schematic cross-sectional view illustrating an embodiment of the present invention and a top view illustrating an electrode arrangement.
  • FIG. 15 is a schematic cross-sectional view illustrating one embodiment of the present invention.
  • FIG. 16 is a schematic sectional view illustrating an embodiment of the present invention.
  • FIG. 17 is a schematic perspective view illustrating the arrangement of electrodes and openings according to an embodiment of the present invention.
  • FIG. 18 is a schematic perspective view illustrating the arrangement of electrodes and openings according to one embodiment of the present invention.
  • FIG. 19 is a schematic plan view illustrating an opening, an electrode shape, an arrangement, and the like according to an embodiment of the present invention.
  • BEST MODE FOR CARRYING OUT THE INVENTION The nitride semiconductor used in the nitride semiconductor light-emitting device of the present invention, G aN, A 1 N or I nN, or these mixed crystal III-V nitride semiconductor (I n x A 1 y G af, N, 0 ⁇ x, 0 ⁇ y, x + y ⁇ 1) .
  • B was used as a group III element, and part of N was replaced with P and As as a group V element. Mixed crystals may be used.
  • the first conductivity type layer and the second conductivity type layer each include at least a first conductivity type nitride semiconductor and a second conductivity type nitride semiconductor.
  • a Group IV or Group VI element such as Si, Ge, Sn, S, O, Ti, or Zr can be used. , G e, S n, and most preferably S i.
  • the p-type impurity is not particularly limited, but includes Be, Zn, Mn, Cr, Mg, and Ca, and preferably Mg is used. Thereby, a nitride semiconductor of each conductivity type is formed, and each conductivity type layer is formed.
  • an insulating substrate such as sapphire or spinel (MgAl 2 ⁇ 4 ) having any one of the C-plane, R-plane, and A-plane as a main surface, SiC (6H, Conventional nitrides capable of growing nitride semiconductors such as ZnS, ZnO, GaAs, Si, and oxide substrates that lattice-match with nitride semiconductors
  • SiC nitride semiconductors
  • a heterogeneous substrate made of a substrate material different from that of a semiconductor, or a nitride semiconductor substrate such as GaN or A 1 N can be used.
  • Preferred heterogeneous substrates include sapphire, spinel, and SiC, which allow good crystal growth.
  • the heterogeneous substrate may be off-angled.
  • the substrate is turned off at an angle of 0.1 ° to 0.5 °, preferably 0.1 ° to 0.2 °, and is preferably turned off in steps. It is preferable to use those that have been used.
  • a nitride semiconductor such as GaN or A1N can be formed on a heterogeneous substrate with a thickness large enough to be taken out as a single substance, and the heterogeneous substrate can be removed to obtain a nitride semiconductor substrate.
  • an element structure to be a light emitting element is formed on the above-mentioned heterogeneous substrate, a low-temperature growth buffer layer, a lateral growth layer described later, or an underlayer made of an undoped nitride semiconductor is used. It is preferable to form the element structure with good crystallinity and using these underlayers as growth substrates.
  • the light emitting device of the present invention has a structure in which a first conductivity type layer 11 and a second conductivity type layer are laminated on a substrate 1 as shown in FIG.
  • the first embodiment has a structure having a current confinement layer having an opening 41 between the first nitride semiconductor layer 4 and the second nitride semiconductor layer.
  • the second conductive type layer 12 has a structure in which a window 40 and a first electrode 20 are partially provided. At this time, as shown in FIG. 2, the window 40 serves as an opening for extracting light emission from the active layer.
  • a light-transmitting film 30 can be provided in the window 40.
  • the first conductivity type layer, the active layer, and the second conductivity type layer are stacked on the first main surface.
  • the light-emitting device of the present invention has a structure in which the reflective layer 10 is provided on the first main surface (FIG. 1) or the second main surface (FIG. 2) of the substrate 1, A structure that efficiently extracts light from the surface and windows can also be used.
  • a reflective layer is provided on the first main surface of the substrate 1
  • a reflective layer is provided between the substrate and the active layer, and in a structure in which a pair of positive and negative electrodes is provided on the same surface side of the substrate, the substrate
  • a reflective layer between the second conductive type layer and the second conductive type layer
  • the light-emitting element of the present invention has a structure in which the first electrode is partially provided on the second conductivity type layer, and a window is mainly provided in a region where the first electrode is not provided,
  • the surface emitting type light emitting element has a structure in which light is efficiently emitted from the surface of the second conductivity type layer, that is, a structure in which a large amount of light perpendicular to the substrate surface is extracted.
  • a large amount of light is emitted from the end face of the active layer, and a small amount of light is emitted in a direction perpendicular to the substrate surface.
  • Luminescent element of the present invention As shown in FIG. 2, the current or carrier can be selectively emitted just below the opening in the surface of the active layer 3 by partially injecting the current or carrier into the opening of the current confinement layer 5. Further, light passes through the window 40 arranged above the opening 41, and light can be efficiently extracted in the direction perpendicular to the substrate surface, in the direction of the white arrow in the figure. Become. This is because, as described above, on the same surface side, the vicinity of the end surface of the active layer near the n-electrode strongly emits light and the luminous efficiency is reduced.
  • the active layer surface is provided by having the current confinement layer. The current flowing through the inside can be controlled, and the light emitting region can be controlled, so that light can be extracted efficiently.
  • the window 40 is provided on or on the second conductivity type layer 12, and the first electrode 20 is partially formed on the second conductivity type layer. As a result, it is formed mainly in a region where the first electrode 20 is not provided. That is, by selectively providing the first electrode 20 on the second conductivity type layer, a window portion for mainly extracting light emitted from the active layer 3 to the outside is provided on the second conductivity type layer. .
  • the first electrode 20 is partially provided on the second conductivity type layer 12 and the second conductivity type layer 12 is
  • the window 40 can be obtained by being exposed.
  • the window 40 may have a recess in the second conductivity type layer 12 as shown in FIG. 3B, and a projection in the second conductivity type layer 12 as shown in FIG. 3C. It may be provided. Further, a translucent film 30 described later may be formed in the window 40.
  • one light emitting element has multiple windows.
  • the 40 can also be formed.
  • a structure in which a plurality of light emitting regions and current injection regions are distributed in the active layer surface can be provided, and light emission can be dispersed.
  • a structure for extracting light from the light emitting surface can be obtained.
  • FIG. 13B in the relationship between the window 40 and the opening 41 of the current confinement layer 5, the image of the window 40 and the opening 41 are formed on the pn junction surface 50. Projecting an image can explain its size, shape, and pattern.
  • the pn junction surface 50 specifically refers to a surface parallel to the active layer surface or the substrate surface, and the window 40 and the opening 41 of each shape are substantially perpendicular to this surface 50.
  • the image can be obtained in the plane.
  • Figure 11 shows the shape and pattern of the window 40 and the opening 41.
  • the image of the window and the opening can be extracted from the light emitting surface (the surface of the second conductivity type layer) by forming at least a part of the image as shown in 1I in Fig. 11.
  • the image of the window (dotted line in the figure) is large enough to cover almost the entire surface of the image of the force opening (solid line), and is formed from the window efficiently. Light can be extracted.
  • one window corresponds to a plurality of openings (solid lines). Part (dotted line) may be provided (Fig. 11B), multiple windows may be provided for one opening (Fig. 11C), and one window may be provided for one opening.
  • a window may be provided and a plurality of windows may be provided (Fig. 11A). That is, the relationship of the window to the opening may be any of one-to-one, many-to-one (n-to-one), one-to-many (one-to-n) [n is an integer of 2 or more].
  • FIG. 11E a configuration in which a plurality of windows are provided for one opening in one part, and one window is provided for a plurality of openings in another part, many-to-many (N vs. n).
  • the current confinement layer 5 provided between the first nitride semiconductor layer 4 and the second nitride semiconductor layer 6 has an opening 41 provided in a plane
  • the composition is a nitride semiconductor layer (third nitride) represented by A 1 x In y G a t -x-yN (0 ⁇ ⁇ 1, 0 ⁇ y ⁇ l, x + y ⁇ 1).
  • Semiconductor layer Conventionally, a current confinement layer made of A1Gan has been known, but the current confinement layer of A1Gan can be a high-resistance layer, and is formed between the current confinement layer and an adjacent layer sandwiching the current confinement layer.
  • the nitride semiconductor containing 1 has a structure in which the current confinement layer and the adjacent layer are laminated, and the generation of cracks and the deterioration of crystallinity become problems.
  • this problem can be avoided by using a quaternary mixed crystal of AlInGaN for the current confinement layer, and the current confinement layer can function as a good current confinement layer and a current blocking layer.
  • This uses a nitride semiconductor containing In and A 1 as the current confinement layer.
  • In nitride semiconductor containing In
  • A1 By containing In, it is possible to prevent the generation of cracks due to the inclusion of A1 by including In, and it is difficult to form a p-type even by diffusion of Mg.
  • the third nitride semiconductor layer is formed by making the A1 composition ratio X larger than the In composition ratio y to be an A1 rich layer, thereby forming a layer having high resistance and a large barrier.
  • the preferred In composition ratio y is 0 ⁇ y ⁇ 0.3, and the reaction between In and A1 caused by increasing the In composition ratio from 0.3 is suppressed to increase the crystallinity. Can be stabilized. More preferably, 0.01.y ⁇ 0.1.
  • the above-described effect of containing In can be obtained, and when it is set to ⁇ 0.1 or less, it can be formed with good crystallinity.
  • the range of ⁇ .02 ⁇ y ⁇ 0.05 is suitably used to extract the effect of containing In, and the range of 05.05 or less is favorable for the reaction between In and A 1. It is possible to form a film with excellent surface morphology by suppressing it.
  • the thickness of the current confinement layer is not particularly limited, but is specifically in the range of 10 nm to 1 / m, preferably in the range of 50 nm to 200 nm. It has good crystallinity and functions well as current constriction. Further, the current confinement layer may be formed as a single film as shown in FIG. 1 or the like, may be formed as a multilayer film as shown in FIG. 5, and may be formed as a superlattice multilayer film structure. it can. As shown in FIGS. 4A to 4D, the current confinement layer is formed by laminating down to the current confinement layer, providing a mask 18 (FIG. 4A), providing an opening 41 (FIG.
  • a second nitride semiconductor layer 6 and the like are laminated (FIG. 4C), and a window, a light-transmitting film 30, and a first electrode 20 are partially formed on the second conductivity type layer corresponding to the opening. (Fig. 4D).
  • a projection is provided on the first nitride semiconductor layer 4 (FIG. 4E), and a layer 5 is grown and embedded in the recess (FIG. 4E). 4F), a form in which the second nitride semiconductor layer 6 is grown.
  • the current confinement layer 5 and the second nitride semiconductor layer 6 need to go through different growth stages, so that the number of growth steps is larger than that in FIGS. 4A to 4D. Therefore, preferably, as shown in FIGS.
  • An embodiment is used in which an opening 41 is provided in the flow constriction layer 5 and the second nitride semiconductor layer 6 is grown.
  • the width of the opening is not particularly limited, but is specifically in a range of 50 nm or more and 10 im or less, It is preferably in the range of 1 m to 5 m, and more preferably in the range of 2 m to 3 jum. This is because, when the nitride semiconductor layer has a structure in which a p-type nitride semiconductor layer is laminated on the active layer, current does not easily spread in the P-type layer, particularly in the plane thereof.
  • the current confinement layer of the present invention may be composed of a multilayer film, and in this case, the current confinement layer may be a layer having a composition different from the composition of the third nitride semiconductor layer.
  • a layer different from the third nitride semiconductor layer may be provided above and below the third nitride semiconductor layer.
  • a nitride semiconductor layer containing In such as InGaN is provided as an upper or lower layer of the third nitride semiconductor layer to form a light absorbing layer, which is taken out of the window through the opening. The shape of the light may be adjusted.
  • a nitride semiconductor layer containing 1 such as A 10 & ⁇ may be provided above or below the third nitride semiconductor layer to form an etching stop layer (evaporation prevention layer). Layer). More specifically, the nitride semiconductor layer containing A1 has a smaller etching rate than other compositions or a nitride semiconductor layer having a smaller A1 mixed crystal ratio, that is, the A1 mixed layer. Taking advantage of the fact that the etching rate decreases as the crystal ratio increases, the nitride semiconductor layer containing A1 such as AlGaN and A1N (A1 highly mixed crystal layer) can be used as a substrate.
  • a third nitride semiconductor layer with a low mixed crystal ratio or another nitride semiconductor layer with a low A 1 mixed crystal ratio is disposed on the upper layer to form a nitride semiconductor layer containing A 1 (A (1 high mixed crystal layer)
  • the nitride semiconductor layer containing A 1 (A 1 high mixed crystal layer) can function as a top layer, and the third nitride semiconductor layer having a smaller A 1 mixed crystal ratio, or A 1
  • an evaporation prevention layer that suppresses the evaporation of the current confinement region other than the opening and the adverse effect on etching when the opening is formed Can function as
  • the effect of this evaporation prevention layer is that the nitride semiconductor layer containing A1 (A1 high mixed crystal layer) power and another nitride semiconductor layer with a small A1 mixed crystal ratio (nitride semiconductor layer containing no A1) This is because the vaporization temperature is higher than
  • the composition and the like of the first nitride semiconductor layer and the second nitride semiconductor layer are not particularly limited.
  • the layer is located below the current confinement layer 5, and the second nitride semiconductor layer is a layer located above the current confinement layer 5.
  • the first nitride semiconductor layer and the second nitride semiconductor layer may have substantially the same composition or different compositions.
  • the interface between them becomes a regrowth interface. It is preferable to use a nitride semiconductor because good regrowth and bonding can be achieved.
  • the first nitride semiconductor layer is provided at a position closer to the active layer than the second nitride semiconductor layer.
  • the second nitride semiconductor layer can be a layer having a large light-transmitting property, or a layer having a different function in each layer as a good contact layer with an electrode.
  • a nitride semiconductor is used so as to have a band gap energy larger than that of the active layer or the well layer.
  • n GaN is used, a nitride semiconductor containing In such as In GaN or a GaN having a lower In mixed crystal ratio, or GaN can be used.
  • a nitride semiconductor layer containing A1 such as A1 GaN preferably allows carriers to be preferably contained in the active layer. Can be confined.
  • the contact layer InN, GaN, A1N, or a mixed crystal thereof can be used.
  • GaN is used to obtain good crystallinity and contact.
  • nitride semiconductor containing In such as InGaN
  • nitride semiconductor containing p It is preferable because a better p-type and a higher concentration of p-type carriers tend to be obtained.
  • a 1 G aN the non-gap energy is lower than other compositions, It can be a layer that is transparent to light emission, enhances light transmission, reduces loss due to light absorption, and enables efficient light extraction from windows.
  • the efficiency of extracting light from the window greatly changes. Specifically, as shown by the outline arrows in FIG. 2, light is extracted from the window in a direction perpendicular to the substrate surface.
  • the first nitride semiconductor layer and the second nitride semiconductor layer By setting the refractive index to be different between and, light extraction will be affected.
  • the first nitride semiconductor layer 4 by setting the first nitride semiconductor layer 4 to have a low refractive index and the second nitride semiconductor layer 6 to have a high refractive index, light emitted from the active layer passes through the opening, Light is efficiently propagated to the second nitride semiconductor layer 6 which is on the low refractive index side, and even if the light is reflected in a region other than the window, the first nitride semiconductor layer 6 moves upward. It functions as a light confinement, and prevents light from returning to the lower side of the active layer again, so that light can be efficiently extracted to the outside of the device.
  • the nitride semiconductor such as A1GaN having a small refractive index has a large bandgap energy that can be suitably used as a cladding layer. If the semiconductor layer is a cladding layer, and the band gap energy is smaller than that of the cladding layer, GaN and InGaN are the second nitride semiconductor layers, and the contact layer is used as a contact layer, a good ohmic contact can be obtained. The resulting laminated structure is realized. When light is extracted upward, light propagates through the first nitride semiconductor layer and the second nitride semiconductor layer.
  • a nitride semiconductor containing In for example, In n G
  • the light absorption loss tends to be larger as compared with other nitride semiconductors not containing I ⁇ , so the nitride containing I ⁇ is preferably contained in the layer immediately below the window. It is preferable not to use a semiconductor, and in particular, there is a large loss in light propagating through the second nitride semiconductor layer from the opening. Therefore, it is preferable that a nitride semiconductor containing In is not used for the second nitride semiconductor layer.
  • the first nitride semiconductor layer and the second nitride semiconductor layer positioned as the upper layer and the lower layer of the current confinement layer are also affected by the relationship with the current confinement layer 5, particularly the third nitride semiconductor layer.
  • the crystallinity of the third nitride semiconductor layer serving as the current constriction layer is affected by the crystallinity of the first nitride semiconductor layer serving as the underlying layer for growth, and the third nitride semiconductor layer serves as the regrown layer.
  • the second nitride semiconductor layer is to be affected by the crystallinity of the third nitride semiconductor layer to be the regrowth surface.
  • the third nitride semiconductor layer composed of a quaternary mixed crystal of InA1Gan which is the preferred embodiment, as the favorable underlayer, InNaN, A1Ga
  • a ternary mixed crystal of N or the like or a binary mixed crystal of GaN for the first nitride semiconductor layer. This is because, as described above, in the growth of a quaternary mixed crystal, the constituent elements, in particular, In and A 1 react with each other, which hinders good growth and tends not to form a film with good crystallinity.
  • the underlying layer is a quaternary mixed crystal and the third nitride semiconductor layer is a quaternary mixed crystal, the quaternary mixed crystal is continuously formed.
  • the crystallinity of the current confinement layer 5 tends to be deteriorated as compared with a case where a binary mixed crystal such as a ternary mixed crystal or GaN is used as an underlayer. If the current confinement layer 5 is not formed with good crystallinity, it may cause a leak current or the like and may not function as a good current blocking layer, which is not preferable.
  • the first nitride semiconductor layer serving as an underlayer is a ternary mixed crystal such as InGaN, A1GaN, or a binary mixed crystal of GaN, With G aN, the most crystalline of these compositions can be formed.With A 1 G aN, a large band gap energy difference can be formed between the active layer and the well layer.
  • a nitride semiconductor containing In such as InGaN
  • it can be formed as a layer that is more elastic than other compositions, and is close to other compositions, especially nitride semiconductors containing A1. By arranging them in this way, they can function as a buffer layer.
  • the first nitride semiconductor layer as such an underlayer is most effective when it is formed in contact with the current confinement layer 5, particularly the third nitride semiconductor layer. For this reason, these underlayers may be arranged next to the quaternary mixed crystal third nitride semiconductor layer as a part of the current confinement layer 5, and more specifically, as shown in FIG. It goes without saying that the current confinement layer made of a film can be a current confinement layer in which the lower layer 5a is used as a base layer and the upper layer 5b is used as a third nitride semiconductor layer, and the base layer is effectively laminated.
  • the second nitride semiconductor layer which is an upper layer of the current confinement layer, is similar to the above-described quaternary mixed crystal being continuously stacked in order to make the current confinement layer a regrowth surface or an underlayer.
  • the second nitride semiconductor layer be made of a ternary mixed crystal such as InGaN or A1GaN or a binary mixed crystal of GaN, A good nitride semiconductor layer can be grown on the constriction layer.
  • InGaN and GaN are preferably used for the same reason as the first nitride semiconductor layer, and the use of A1GaN is preferably a nitride semiconductor containing A1.
  • composition of the above Compared to the composition of the above, it has excellent pit reduction effect, forms a good laminated structure surface, can form a window surface excellent in light extraction, and has surface flatness suitable for forming electrodes 20 It can be a layer, and on the other hand, it can be a layer with less loss of light in the propagation of light, which is preferable.
  • a mixed crystal nitride semiconductor having fewer constituent elements (group III elements) than the third nitride semiconductor layer that is, a ternary mixed crystal (InGaN, A1GaN), binary
  • a mixed crystal GaN, A1N
  • each layer can be grown with good crystallinity, and the function of each layer, specifically, the cladding layer and the second layer in the first nitride semiconductor layer
  • the nitride semiconductor layer has a structure that can function as a light propagation layer and a contact layer.
  • the second nitride semiconductor layer 6, which is the upper layer of the current confinement layer 5, is formed of a superlattice multilayer film, or at least a part thereof is provided with a superlattice multilayer film, as shown in FIG.
  • the mobility of carriers in the horizontal direction and the in-plane direction of the substrate surface is increased, and the resistance value of the second nitride semiconductor layer 6 is substantially reduced, and the resistance value and operating voltage of the device are reduced. be able to. This is thought to be due to the provision of the superlattice multilayer film on the current confinement layer, whereby the two-dimensional electron gas facilitates the lateral movement of carriers by traveling.
  • two-dimensional electron gas is generated between the high impurity concentration layer and the low impurity concentration layer by modulation doping, and it is assumed that the resistivity is reduced by the influence of the two-dimensional electron gas.
  • a nitride semiconductor layer with a large band gap doped with an n-type impurity and a non-doped nitride semiconductor layer with a small band gap are laminated.
  • the barrier layer side is depleted, and electrons (two-dimensional electron gas) ) Accumulates.
  • the two-dimensional electron gas is formed on the side with the small band gap, the electrons are not scattered by impurities when traveling, so that the mobility of the electrons in the strained superlattice increases and the resistivity decreases.
  • the superlattice layer with an n-type impurity, it is desirable to dope the first nitride semiconductor layer having a large band gap energy with a large amount.
  • the preferable doping amount is adjusted to a range of 1 ⁇ 10 17 / cm 3 to 1 ⁇ 10 20 / cm 3, more preferably 1 ⁇ 10 18 / cm 3 to 5 ⁇ 10 19 cm 3 .
  • each layer of the superlattice multilayer film is specifically 100 A or less, preferably 75 A or less to achieve a critical film thickness or less, and more preferably 5 OA or less.
  • composition of the superlattice multilayer film, the laminated pair and the like are not limited, and two or more layers having different compositions may be alternately or periodically laminated.
  • a nitride semiconductor containing A1 A multilayer film having a nitride semiconductor (A layer) and a nitride semiconductor (B layer) having a different composition
  • Membrane, etc. Specifically, A l xG at- X N (0 ⁇ x ⁇ l) / I n y G a N (0 ⁇ y ⁇ l). It is advisable to increase the dog gap energy.
  • a transparent film that satisfies the following conditional expression can be used.
  • the refractive indices of the second nitride semiconductor layer 6, the translucent film 30, and the sealing member (or gas sealing) 100 are n L, n 2 , and n 3 , respectively.
  • the film thicknesses are dd 2 and d 3 , respectively.
  • the material of the light-transmitting film is not particularly limited, and may be the same as the material of the reflective layer described later.
  • the insulating film and the dielectric film are preferably used.
  • a light-transmitting film made of these insulating films and dielectric films is formed so as to cover the side surfaces of the convex portions 51, thereby insulating the pair of positive and negative electrodes. It can also function as a short-circuit prevention layer.
  • the second nitride semiconductor layer can be replaced with the active layer 5 and applied.
  • the light-transmitting film of the present invention is not limited to this, and may be any film that transmits light.
  • a film that satisfies the above formula is provided.
  • By forming the light-transmitting film in this manner light emitted from the window can be efficiently extracted to the outside of the element without loss, so that the light extraction efficiency is improved, A light-emitting device using a light-emitting element has excellent light-emitting output. Further, such a light-transmitting film seals a light-transmitting resin as shown in FIGS. 9A and 9B in various forms of light-emitting devices using the light-emitting element 200 as shown in FIG. As shown in FIG.
  • each part in the figure is a sealing member 100, a lead electrode 101, a reflecting part (external reflecting mirror) 102, a wire 103, an internal electrode 104, an external electrode 1 5, a base (106, 107), a housing 108, a light extraction window 109, and a light emitting element chip 200.
  • the first nitride semiconductor layer 4 may be used as a second nitride semiconductor layer, and the light-transmitting film may be used in place of the second nitride semiconductor layer. That is, the second nitride semiconductor layer can be provided as a film that transmits light emitted from the opening of the current confinement layer including the third nitride semiconductor layer 5.
  • the nitride semiconductor layer interposed between the opening of the current constriction layer and the window is formed according to the above-mentioned conditional expression so as to be a light-transmitting film, and a multilayer film is formed therebetween.
  • the uppermost layer is made of a light-transmitting film between the uppermost layer in the window and the layer below the uppermost layer so as to satisfy the above conditional expression.
  • a second nitride semiconductor layer 6 is formed on the opening 41, and a contact layer 7 is further formed as an uppermost layer (cap layer).
  • the contact layer 7 is formed as a light-transmitting film, and is formed so as to satisfy the above-mentioned conditional expression of the light-transmitting film in relation to the second nitride semiconductor layer 6 located thereunder. Further, by applying this, it is also possible to apply a structure in which the contact layer 7 for ohmic contact with the electrode 20 and the uppermost layer in the window portion have different compositions. Specifically, as shown in FIGS.
  • the window 40 when the distance from the active layer is different between the uppermost layer of the window portion 40 and the contact layer in contact with the electrode 20, the window This can be achieved by forming a multilayer film structure in the convex portion or the concave portion in the portion 40 and making the uppermost layer in a region in contact with the electrode 20 and the uppermost layer in the window portion different.
  • a specific laminated structure as a multilayer film in which the uppermost layer (1) and the layer (2) located thereunder are laminated, a region other than a window portion for forming an electrode is exposed at a depth where the layer (2) is exposed. By removing a part, a window 40 having a convex portion as shown in FIG. 3C is formed.
  • the uppermost layer becomes the layer (1), and when the surface on which the electrode 20 is formed is removed.
  • the structure is a lower layer (2), which is the exposed surface of.
  • the exposed layer (the uppermost layer) in the window portion becomes the lower layer (the uppermost layer). 2), and the surface on which the electrode 20 is formed (the uppermost layer) can be configured to be the upper layer (1). Also, as shown in FIG. 3B, by removing a part of the window portion at a depth where the lower layer (2) is exposed, the exposed layer (the uppermost layer) in the window portion becomes the lower layer (the uppermost layer). 2), and the surface on which the electrode 20 is formed (the uppermost layer) can be configured to be the upper layer (1). Also, as shown in FIG.
  • the concave portion due to the opening of the current confinement layer 5 is carried over to the upper layer, and the uppermost layer is formed.
  • the top layer immediately above the opening is laminated with a concave shape at the stage of lamination, the area other than the concave part is partially removed so that the concave part in the uppermost layer has a substantially flat surface.
  • the above-mentioned upper layer (1) is the uppermost layer of the window 40, and the electrode 20 is formed on the lower layer (2) exposed by the partial removal. It can be a laminated structure having an upper layer.
  • the uppermost layer serving as the surface on which the electrode 20 is formed can be a contact layer, and a semiconductor having an excellent contact layer is used. It is possible to use a nitride semiconductor having a composition excellent in light extraction as the uppermost layer.
  • the following semiconductor multilayer film and dielectric film can be used.
  • semiconductor multilayer film semiconductor multilayer film
  • a structure in which A layers having a low refractive index and B layers 10b having a high refractive index are alternately laminated More preferably, by laminating two or more of either the A layer or the B layer, it functions as a good reflection film.
  • a layer having a different composition from the A and B layers may be provided. As shown in FIG. 1, the structure is such that the A layer 10a and the B layer 10b are alternately stacked, and the A and B layers are paired to form one or more pairs, preferably two or more pairs.
  • the difference in refractive index between the A layer and the B layer can be increased by increasing the difference in the A 1 composition ratio (ct ⁇
  • 8), and a reflective layer with high reflectance is formed. Is done. Specifically, by setting the difference ( ⁇ _) in the A1 composition ratio to 0.3 or more, the light is reflected by the reflective layer and light is well extracted from the window, and preferably 0.5 or more. As a result, a reflection layer having a high reflectance is formed, and light emitted upward from the window can be efficiently extracted. In addition, it is preferable to use G a ⁇ ⁇ ⁇ with A 1 composition ratio] 3 0 for the ⁇ layer.
  • a first conductivity type impurity may be added to each layer of the semiconductor multilayer film layer, and a reflection layer may be provided inside the first conductivity type layer as the first conductivity type layer.
  • doping impurities deteriorates the crystallinity, so that each layer is undoped to form an electrode 21 of the first conductivity type layer between the first conductivity type layer and the substrate, or as shown in FIG.
  • the element structure provided thereon can be formed with good crystallinity.
  • a part of the reflection layer can be provided in the first conductivity type layer, and a part of the reflection layer can be doped with an impurity.
  • the reflective layer when the reflective layer is formed of a dielectric film, either a single film or a multilayer film may be used. However, preferably, a high reflectivity can be obtained by using a multilayer film.
  • T I_ ⁇ 2 as a material of high refractive index, Z r O 2, H f ⁇ 2, S c 2 Rei_3, Y 2 ⁇ 3, MgO, a l 2 ⁇ 3, S i 3 N 4, at least one of the T hO 2 can be selected, a low refractive S i ⁇ 2, Th as material of rate
  • L a F 3, Mg F 2, L i F, Na F can at least one selected among N a 3 A 1 F 6, and these high refractive index material, and low refractive index material Are appropriately combined to form a reflective layer as a multilayer film layer.
  • Si 2 , Ti 0 2 , Zr 2 , ZnO, A 1 2 3 , MgO, and polyimide are a single film, preferably a multilayer film, and more preferably It is formed with a film thickness that satisfies.
  • the thickness of the reflective layer is not limited to the above-mentioned film thickness. Even if each layer is changed from the wavelength of 1 to 4, the reflectance is deteriorated, but the reflective layer can function as a reflective layer.
  • the material of the reflective layer is not limited to the above, and the reflective layer may be formed of a reflective film made of a metal such as Au, Al, Pt, and Rh.
  • the first electrode 20 partially provided on the second conductivity type layer is an electrode that is electrically connected to the second conductivity type layer and mainly causes an omic contact.
  • it may be a translucent electrode or a non-translucent electrode.
  • a light-transmitting electrode When a light-transmitting electrode is used, light can be mainly extracted from the window portion, transmitted through the first electrode 20 and extracted therefrom, and can be a light-emitting element that emits surface light from the entire surface of the second conductivity type layer.
  • the first electrode 20 is formed of a thick film and the light transmittance is extremely low, or when the first electrode 20 is an opaque electrode, the light emitting element can selectively take out light from the window.
  • a small point light source or an array light source can be used, and as shown in FIG. 8, the windows 20 can be arranged in a row to provide an inline light source.
  • the second electrode 22 is provided on the first electrode 20, as shown in FIG. 13 and the like, and serves as a pad electrode for wire bonding. Further, when the first electrode 20 is a light-transmitting electrode, the third electrode 23 This will spread the current. Since the light-transmitting electrode has a large resistivity, the current hardly spreads in the first electrode 20.However, the third electrode electrically connected to the second electrode is connected to the first electrode. By extending and partially forming the electrode on the second electrode 20, the current flow can be expanded in the first electrode surface.
  • the first electrode 20 for ohmic contact separates a window serving as a light extraction port from an electrode forming surface serving as a current injection unit.
  • the light transmittance lower than in the case of transmitting light through the window or the window.
  • the light-emitting element of the present invention mainly aims to extract light from the window portion, when the first electrode 20 is a translucent electrode, the electrode is dropped.
  • Such a light emitting element can be obtained by providing the first electrode 20 having a light transmittance smaller than that of the window so that the light from the window is prioritized over the light extracted therefrom.
  • the first electrode 20 may be a light-transmitting electrode 20 or an opaque film having a large film thickness and a reduced sheet resistance.
  • the second electrode 22 may be formed in a rectangular shape having a diameter of ⁇ or more or a length of a side so as to have a size in which a ball is formed.
  • the third electrode 23 electrically connects the first electrode 20 and the second electrode 22, as shown in FIGS. 12A and 12C, and is connected to the first electrode 20.
  • the current from the second electrode 22 is efficiently conducted to the first electrode 20 and the current spread in the surface of the second conductivity type layer surface 7 s. Can be injected. This is to improve the sheet resistance when the first electrode 20 is a translucent electrode and to make it difficult to spread the current in the in-plane direction. Conducts current to the first electrode 20 via 23 to achieve good current injection and diffusion, resulting in excellent luminous efficiency Light emitting element.
  • the shape of the third electrode 23 having such a low resistance is not particularly limited, and specifically, the shape of the opening or the window is set so as to cover the window or the opening. It is preferable to form them by arranging them on both sides along the longitudinal direction, preferably as shown in FIGS. 12B and 12C. This is because current is intensively injected into the opening where the current is selectively formed by the current constriction layer. At this time, the periphery of the opening or the window is surrounded by the current or the window so as to surround the opening or the window. This is because, by wiring along the opening shape of the opening and the opening, the current can be efficiently injected into the opening serving as the current constriction region.
  • the third electrode 23 only describes one embodiment thereof, and does not limit the shape and pattern of the third electrode 23. Needless to say, they may be arranged in the form of a branch branched from one to a plurality.
  • the third electrode 23 is not limited to the case where it is formed on the first electrode 20 as shown in FIG. 3 and the like. Even if the first electrode 20 is formed so as to cover the electrode 23 after the formation of the electrode 23, the above-described operation can be obtained, and such a form is also included. It goes without saying that a structure may be formed simultaneously with the second electrode 22 which is an electrode, that is, the second electrode 22 may be extended on the first electrode 20 and wired.
  • the openings and the windows are arranged so as to surround the vicinity of the periphery thereof.However, in the form of surrounding these closed regions, it does not mean that all of them are surrounded, but at least a part of the periphery.
  • the opening and the window have a longitudinal direction, the current is efficiently injected along the longitudinal direction if they are provided substantially in parallel with each other along the longitudinal direction. Therefore, the current diffusion function can still be sufficiently performed 1 ".
  • the difference between Fig. 12B and Fig. 12C is that the diffusion spreads almost completely around the window and opening. Even if a third electrode 23 is provided (Fig. 12B) and the third electrode 23 is provided along the longitudinal direction (Fig. 12C), almost the same excellent current spreading is obtained. Is realized.
  • the electrode provided in the second conductivity type layer has been described above. Next, the electrode provided in the first conductivity type layer will be described.
  • the drawings attached to the specification of the present application show a so-called flip-chip type element in which a pair of positive and negative electrodes are provided on the same surface side of the substrate, but the light emitting element of the present invention is not limited to this. So that the A structure in which a pair of positive and negative electrodes are opposed to each other with a plate interposed therebetween may be used.
  • FIG. 3B a structure in which the reflection layer 10 is used as one electrode and an electrode formed on an element structure provided on the front surface side of the substrate can be used as a counterpart can be adopted. .
  • the current flow is preferably perpendicular to the substrate surface.
  • the electrodes 21 and 24 of the first conductivity type layer when a pair of positive and negative electrodes are provided on the same surface side of the substrate will be described below.
  • the electrodes 21 surround the pn junction and the convex region 51 having the active layer. Is preferably formed.
  • the electrode 21 is mainly an electrode for ohmic contact with the first conductivity type layer
  • the electrode 24 is a pad electrode for wire bonding.
  • the convex portion 51 may be formed so as to substantially surround the entire region.
  • FIGS. 13 to 16 are partially open and surround the convex portion 51. As shown, it may be formed.
  • FIG. 12B in a shape in which a plurality of rectangular or strip-shaped convex portions 51 having a longitudinal direction are connected, along the longitudinal direction as in the case of the third electrode 23 described above.
  • the electrode 21 in the case of having a longitudinal region, particularly an opening and a window in the longitudinal region, by disposing the electrode 21 in the vicinity of the convex portion 51 along the longitudinal direction, The current is efficiently diffused and injected into the opening in the longitudinal region and the lower part of the window.
  • the electrodes 22 and 24 for bonding are arranged diagonally with respect to the rectangular element chip, and each electrode is positioned near one corner. It may be arranged in a form, or may be arranged close to a rectangular chip along one side thereof. By arranging these electrodes, it is possible to increase the light emitting area, and when the electrodes 22 and 24 are arranged along one side, the chip is used for chip bonding and wire bonding to the electrodes. Since the electrode is biased on one side, wire bonding is facilitated, which is preferable.
  • the shape of the element chip is not limited to a rectangular shape, but may be a rhombus shape, a trapezoidal shape, a parallelogram shape, or a polygonal shape.
  • the second electrode 22 is shown in FIG. As described above, it may be provided on the convex portion 51, and is extended on the electrode forming surface 2s of the second conductivity type layer via an insulating film or the like so as to have almost the same height as the electrodes 21 and 24. It can also be provided. Further, as a material used for the above-mentioned electrode, a conventionally known electrode material of a nitride semiconductor and a laminated structure can be used. Specific examples of the electrode material include Ni Au WPt Ti Rh A1 and the like.
  • the light emitting element chip 200 such as an LED is usually used as a light emitting device sealed and packaged by a sealing member 100 as shown in FIG. Therefore, as shown in FIG. 10, the light extraction efficiency in the light emitting device can be increased by the refractive index between the window portion 40 and the sealing member 100 or the refractive index between the light transmitting film and the sealing member. .
  • the sealing member is made of a light-transmitting material that transmits light from the light emitting element chip 200.
  • the sealing member (mold member) 100 includes: Epoxy resins (1.5.1.6) and silicone resins (1.4.1.5) are commonly used as translucent resins (refractive index in parentheses).
  • a sealing material containing a diffusion material such as polyimide resin or filler, particles such as phosphor and pigment, micron-order particles, and particles of sub-micron order can be partially used.
  • the active layer 3 has at least a nitride semiconductor containing In, and has an In x A 1 y G a y N (0 ⁇ x ⁇ 1, 0 ⁇ y ⁇ 1, 0 ⁇ x + A nitride semiconductor represented by y ⁇ 1) is used.
  • a nitride semiconductor containing In may be at least one of a well layer and a barrier layer having a quantum well structure, or may be both layers.
  • a heterogeneous substrate is used as the substrate, as shown in FIG. 1 and the like, an element structure in which the first conductive type layer 11, the active layer 3, and the second conductive type layer 12 are stacked, and the substrate
  • a low-temperature growth buffer layer is used as the underlayer 12, crystallinity can be improved.
  • a l xG a i- X N (0 ⁇ x ⁇ 1) can have use of.
  • a nitride semiconductor grown by EL0G (Epitaxially Laterally Overgrowth) and a lateral growth layer 60 are used as a base layer provided on the substrate, a growth substrate having good crystallinity can be obtained.
  • the E LOG layer as shown in Fig. 6, a nitride semiconductor layer 13a is grown on a substrate and a protective film on which nitride semiconductor growth is difficult is provided on the surface.
  • FIG. 6B Lateral growth results in a layer 13b of nitride semiconductor that also grows over the mask area.
  • an opening may be provided in a nitride semiconductor layer grown on a heterogeneous substrate, and a layer may be formed by growing laterally from a side surface of the opening.
  • the feature of the nitride semiconductor grown by lateral growth (ELOG) or the nitride semiconductor layer 13b grown thereon is that it has a surface with a crystalline distribution.
  • a region A having good crystallinity and a region B having poor crystallinity are provided.
  • the good crystallinity region A and the bad crystallinity region B are determined mainly by evaluating the dislocation density, and the dislocation density of the good crystallinity region A The ratio depends on the crystallinity of the underlayer 13a, but a dislocation density difference of 1/10 or more, preferably 1Z100 or more appears.
  • the dislocation density in the region A having good crystallinity is l X l O / cm 2 or less, preferably 1 X 1 C ⁇ Zcm 2 or less.
  • the dislocation density in the bad region B is higher than 1 ⁇ 10 3 Z cm 2 , and when there are many defects, it is higher than 1 ⁇ 10 13 / cm 2 .
  • the in-plane distribution of threading dislocations is such that the threading dislocations in nitride semiconductor 13b extend in the lateral direction during lateral growth and do not propagate in the film thickness direction.
  • the threading dislocations are reduced in the area A grown in the direction A.
  • hatching is applied to tighten the low defect area A
  • Figs. 6A to 6C show the laterally grown layer 13b.
  • FIGS. 6D and 6E show a low defect area A and a high defect area in the lateral growth layer 13 b (60) surface or in the pn junction surface 50. This shows the distribution of the region B.
  • a current is selectively injected into the active layer in a favorable region, and a high output, excellent device life, and high luminous efficiency can be obtained.
  • the relationship between the image of the low defect region A and the image of the opening is as follows. However, in the above-described relationship between the image of the window portion and the image of the opening portion, it is preferable that the light emitting element has a relationship in which the window portion is replaced with the low defect area A.
  • the mask shape at the time of the lateral growth that is, the lateral growth area in the substrate surface, and the mask shape when using a mask
  • a nitride semiconductor in the form of a projection or an island is formed and grown from the nitride semiconductor, thereby exhibiting lateral growth, thereby forming a film with lateral growth.
  • FIGS. 12 to 16 in a structure in which a pair of positive and negative electrodes are provided on the same surface side of a substrate, a pn junction, specifically an active layer, There is a so-called flip-chip type element in which a projection 51 having a conductive type layer is provided partially on a substrate surface.
  • the form of the convex portion 51 will be specifically described.
  • the shape may be substantially rectangular, and the bonding electrode 24 is provided with a part of the rectangular shape (corner).
  • the convex shape 51 with the region formed Fig. 14A
  • the shape may be as shown.
  • FIG. 14A The shape may be as shown.
  • the shape is such that a plurality of rectangular regions and strip-shaped convex portions 51 are connected.
  • the electrodes of each conductivity type layer are formed around the opening, the window, or along the longitudinal direction, thereby forming a gap between the electrodes. This is because the flowing current can be dispersed in the pn junction plane and concentrated in the opening, and the electrodes of each conductive type layer are connected to the side surface of the convex region 51 and the top surface in FIG.
  • by increasing the length of the side of the protrusion 51 it is possible to arrange the electrodes of each conductive type layer in a close and long area, reduce the distance between the positive and negative electrodes, and increase the large current.
  • the convex region 51 is provided with a stripe-shaped or rectangular-shaped projection (the window in the figure is provided). It is preferable to form a protruding region extending in the longitudinal direction in view of the arrangement of the electrodes and the flow of current. As shown in the figure, the convex portion 51 is formed by joining a strip-shaped region and a stripe-shaped region. As shown in FIG. 8, a plurality of stripe-shaped protrusions 51 are provided independently, that is, a pn junction (active layer) is separately provided and electrically connected to an electrode or an electrode.
  • the shape may be electrically joined by wiring.
  • a window and an opening that make the longitudinal direction substantially parallel to the projected area of the projection 51, preferably in the striped area it is preferable that the light emission is preferable in terms of the current injection and light emission.
  • An element is preferably obtained.
  • a shape in which a window portion and an opening portion may be provided also in a region where stripe-shaped protrusions are connected. This is because, as can be seen from the figure, the convex portion 51 has a shape in which a plurality of stripe-shaped regions are connected, so that the convex portion 51 extends in a direction substantially perpendicular to the window in the drawing. This is because the area 51) is striped.
  • FIG. 8 shows an example in which, as described above, a plurality of stripe-shaped regions in which the convex portions 51 have the longitudinal direction are provided with the active layer being separated.
  • a region indicated by a short arrow in the drawing may be one light emitting element, and a region indicated by a long arrow may be one element.
  • the pn junction is separated, and a plurality of independent projections 51 can be electrically connected (connected) by a conductive material to form a light-emitting element. (Aperture, window and projection of current confinement layer 5 1)
  • FIG. 1 is a cross-sectional view schematically showing a part of the AA cut surface (one stripe-shaped protruding portion of the convex portion 51) or the BB cut surface in FIG. 12, and FIG. FIGS. 16A and 16B show a state in which a plurality of openings or windows can be received in these cut surfaces.
  • FIGS. 1 and 16 show the relationship between the opening and the window in the region of the convex portion 51 or the strip-shaped protruding portion of the convex portion 51 at a cross section perpendicular to the stripe direction.
  • FIG. 15 shows a mode in which an opening 41 that opens on the side surface of the projection 51 according to the present invention is provided in the current confinement layer 5.
  • the current confinement layer by providing the current confinement layer with an opening at the end face of the projection 51, the current confinement layer is provided between the electrode 21 of the first conductivity type layer disposed close to the end face or the side face of the projection 51.
  • the light is efficiently guided to the side surface of the projection without being affected by the layer, and light can be extracted from the side surface. As shown in FIG.
  • FIG. 15A in the form of opening on the side surface of the projection 51, the opening and the electrodes 20 and 23 are arranged so that their images overlap each other. It has a shape that allows a large amount of current to be distributed in the plane to the opening, and allows a large amount of light to be extracted from the side surface of the projection.
  • FIG. 15B when the openings and the electrodes 20 and 23 are arranged so as not to overlap, as shown in FIG.
  • FIG. 15 shows a cross-sectional structure in a part of the convex region, similarly to FIG. 16, and the structures of FIGS. 15A and 15B can be provided in a part of the convex part. It may be applied to almost all.
  • the shapes of the opening, the window, and the protrusion are respectively the current path, the luminous efficiency, This is an important factor in determining the directivity of the light emitting element chip.
  • FIG. 18A by providing a stripe-shaped opening 41 substantially parallel to the stripe direction with respect to the stripe-shaped protrusion, light is extracted in the stripe direction.
  • FIG. 18B a stripe-shaped light emission is similarly obtained from the upper surface even when the openings are arranged substantially parallel to the stripe direction with respect to the stripe-shaped protrusions.
  • a light emitting device shown in FIG. 14 is manufactured, and at this time, the first conductivity type layer 11 is formed as an n-type layer, and the second conductivity type layer 12 is formed as a p-type layer.
  • the present invention is not limited to this, and conversely, the first conductivity type layer may be a p-type layer, and the second conductivity type layer may be an n-type layer.
  • a heterogeneous substrate composed of a sapphire substrate having the C surface as the main surface and the orientation flat surface as the A surface is set in the reaction vessel, the temperature is set to 501 ° C, hydrogen is used as the carrier gas, and the raw material gas is used.
  • a buffer layer of GaN is grown to a thickness of 20 OA on a sapphire substrate using ammonia and TMG (trimethylgallium). After the growth of the buffer layer, stop only TMG and raise the temperature to 150 ° C. When the temperature reaches 150 ° C, use TMG, ammonia, and silane as the source gas, and use undoped GaN.
  • the underlayer 13a is grown to a thickness of 5 m. As shown in Fig.
  • a stripe-shaped photomask is formed on the underlayer 13a, and a stripe width of 6 ⁇ and an opening of 14! ! !
  • a mask 18 of i ⁇ ⁇ 2 is formed with a thickness of 0.5 ⁇ m.
  • the stripe direction of the mask shall be perpendicular to the sapphire A surface.
  • undoped A1 is used on the underlayer 13 at 1050 ° C using TMA (trimethylaluminum), TMG, and ammonia gas as source gases. . 5 G a 0. 5 N ( A layer 10 a), the raw material gas TMG, ammonia gas as and Ichipu of G a N (B layer 10 b), and three pairs stacked alternately (A / BZAZBZA / B), forming a reflection layer 10; At this time, the thickness of each layer is (4 n).
  • Active layer 3 In which Si is doped with 5 ⁇ 10 18 cm 3 . oi G a o. 99 N barrier layer (100A), undoped In. a. Multi-quantum well structure (MQW) with a total thickness of 55 OA by laminating 89 N well layers (50 A), barrier layers, well layers, well layers, barrier layers, well layers
  • P-side cladding layer (first nitride semiconductor layer 4): p-type A 1 doped with 1 ⁇ 10 2 ° / cm 3 of Mg. . 2 Ga. . 8 N, the third layer having a thickness of 4 nm, 1 to Mg ⁇ 10 2O / cm 3 dough flop was I n. . 03 G a 0. 97 N, and a fourth layer having a thickness of 2. 5 nm, as a pair, alternately five layers, 5 and pair laminated, finally superlattice formed by laminating a third layer multilayer current confinement layer 5 structure:.. undoped a 10. ⁇ I n 0 03 Gao 87 n, 100 nm
  • a mask 18 is provided and etching is performed to remove a part thereof.
  • a stripe-shaped opening 41 is formed with a width of 2 ⁇ and a length of 20 ⁇ m. Formed with ⁇ . At this time, the opening 41 is arranged in the low defect region ⁇ of the lateral growth layer as shown in the figure.
  • p-side contact layer (second nitride semiconductor layer 6)
  • p-type GaN doped with Mg at 1 ⁇ 10 2 ° / cm 3 is formed to a thickness of 1 ⁇ m.
  • the n-type contact layer is partially exposed to form an electrode formation surface, and a transparent electrode (first electrode 20) containing Ni and Au is formed on the p-type contact layer surface with a thickness of 20 nm and a width of 3 ⁇ m. m, length 2 10 jum, excluding the stripe area covering the entire surface of the opening 41 You.
  • An n-electrode 21 containing W and A1 is formed on the exposed n-type contact layer.
  • pad electrodes 22 and 23 are provided for each electrode.
  • a p-type contactors coat layer 6 surface, the window portion 4 0 of the stripe area to form a Z n O 2 transparent film 3 0 at a film thickness of the above-mentioned conditional expression.
  • the light emitting device chip thus obtained is die-bonded into a cup of the reflecting portion 102 of the lead electrode 101 as shown in FIG. 9A, and a translucent resin (epoxy resin, refractive index Mold at 1.5) to make a lamp-type light emitting device.
  • the nitride semiconductor light-emitting device obtained according to the present invention can actively and efficiently extract light above the light-emitting surface, and a light-emitting device capable of improving light extraction efficiency and increasing output can be obtained.
  • a structure can be obtained in which current is injected into the active layer by concentrating on the opening in the minute region, and a light-emitting element with excellent high-speed response can be obtained. It can be suitably used for optical communication.
  • the second conductivity type layer should be a p-type layer.
  • the current confinement layer plays a role of current diffusion for diffusing a current path into the plane, so that a light emitting device with excellent luminous efficiency can be obtained.

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Abstract

L'invention concerne un appareil semi-conducteur nitrure possédant une meilleure efficacité d'extraction de lumière et une production de lumière élevée. Sur un substrat, une structure multicouches est formée avec une couche (11) d'un premier type de conductivité, une couche (3) active et une couche (12) d'un second type de conductivité. Dans cette couche (12) de second type de conductivité, entre une première couche (4) semi-conductrice nitrure et une seconde couche (6) semi-conductrice nitrure de couverture, on trouve entre les deux une troisième couche (5) semi-conductrice nitrure d'InAlGaN qui agit comme une couche de constriction de courant dotée d'une ouverture (41). Sur la surface de la couche (12) de second type de conductivité, on trouve, partiellement formés, une électrode (20) et une fenêtre (40) ou un film (30) transparent dans la fenêtre (40). En conséquence, on peut extraire beaucoup de lumière de la face supérieure de la structure.
PCT/JP2001/005097 2001-06-15 2001-06-15 Appareil semi-conducteur d'emission de lumiere Ceased WO2002103811A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
PCT/JP2001/005097 WO2002103811A1 (fr) 2001-06-15 2001-06-15 Appareil semi-conducteur d'emission de lumiere
TW091113100A TW558846B (en) 2001-06-15 2002-06-14 Nitride semiconductor light emitting element and light emitting device using the same
PCT/JP2002/005998 WO2002103813A1 (fr) 2001-06-15 2002-06-17 Element emetteur de lumiere a semi-conducteur au nitrure, et dispositif emetteur de lumiere utilisant cet element
JP2003506019A JP3956941B2 (ja) 2001-06-15 2002-06-17 窒化物半導体発光素子及びそれを用いた発光装置

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US20220052242A1 (en) * 2020-08-17 2022-02-17 Japan Display Inc. Display device

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JPS60253283A (ja) * 1984-05-29 1985-12-13 Toshiba Corp 半導体発光素子
JPS618981A (ja) * 1984-06-23 1986-01-16 Oki Electric Ind Co Ltd 半導体発光素子
JPH0541537A (ja) * 1991-08-02 1993-02-19 Omron Corp 発光領域制限型発光ダイオード及びその製造方法
JPH06334213A (ja) * 1993-05-27 1994-12-02 Sharp Corp 半導体発光素子およびその製造方法
JPH09129932A (ja) * 1995-10-30 1997-05-16 Nichia Chem Ind Ltd 窒化物半導体発光素子
JPH10163531A (ja) * 1996-11-26 1998-06-19 Nichia Chem Ind Ltd 周縁に電極を有する発光ダイオード
JPH10190063A (ja) * 1996-12-25 1998-07-21 Sharp Corp 半導体発光素子および半導体発光装置
JP2000174340A (ja) * 1998-12-04 2000-06-23 Mitsubishi Cable Ind Ltd ＧａＮ系半導体発光素子

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JPS60253283A (ja) * 1984-05-29 1985-12-13 Toshiba Corp 半導体発光素子
JPS618981A (ja) * 1984-06-23 1986-01-16 Oki Electric Ind Co Ltd 半導体発光素子
JPH0541537A (ja) * 1991-08-02 1993-02-19 Omron Corp 発光領域制限型発光ダイオード及びその製造方法
JPH06334213A (ja) * 1993-05-27 1994-12-02 Sharp Corp 半導体発光素子およびその製造方法
JPH09129932A (ja) * 1995-10-30 1997-05-16 Nichia Chem Ind Ltd 窒化物半導体発光素子
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JPH10190063A (ja) * 1996-12-25 1998-07-21 Sharp Corp 半導体発光素子および半導体発光装置
JP2000174340A (ja) * 1998-12-04 2000-06-23 Mitsubishi Cable Ind Ltd ＧａＮ系半導体発光素子

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