JPH0637352A - Optical coupling device and manufacturing method - Google Patents

Abstract

(57) [Summary] [Object] To provide an optical coupling device having high performance reliability and low manufacturing cost, and a manufacturing method thereof. A light-shielding cap 10 having a light-emitting element 13 and a light-receiving element 14 on a bottom surface of a concave portion of an insulating concave case 20 having conductor wirings (1-1) and (1-2), and a reflecting surface 9 on an upper surface thereof. In the optical coupling device provided with, the light-transmissive light guide plate 24a is provided on the light-receiving element 14 and the light-emitting element 13, and the conductor wiring (1-3) provided on the lower surface of the light-transmissive light guide plate 24a.
And bump-connect the upper electrodes of the light-receiving and light-emitting elements 14 and 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical coupling device and a method of manufacturing the same, which has high performance stability and reliability,
Moreover, the present invention relates to a chip-type optical coupling device and a manufacturing method thereof, in which the manufacturing method is easy, the working time required for manufacturing is short, and the manufacturing cost can be reduced.

[0002]

2. Description of the Related Art An optical coupling device of this type, particularly a chip type optical coupling device, has conventionally been constructed as shown in FIGS. 13 (a) to 13 (c). 13A shows a perspective view of a conventional chip type optical coupling device, and FIG. 13B shows FIG.
13A is a sectional view taken along line AA, and FIG. 13C is a sectional view taken along line BB in FIG. 13A. The conventional chip-type optical coupling device described above has an insulating property in which conductor wirings (1-1) and (1-2) for connecting to a light emitting element and a light receiving element are provided on the inner surface of a recess of a case having an inner surface formed in a concave shape. The concave case 20, the conductor wirings (1-1) and (1-2) extending on the bottom surface of the concave portion of the insulating concave case 20, and the bottom electrodes (3) of the light emitting element and the light receiving element installed in the concave portion. -1), (4-1)
Of the chip type light emitting element 3 and the light receiving element 4 connected to each other by a conductive adhesive (not shown), and the upper electrodes (3-) of the chip type light emitting element 3 and the light receiving element.
2) and (4-2), the conductive wires 5 and 6 connected to each other by wire bonding, and the chip type light emitting element 3 and the light receiving element 4 are embedded in the recess of the insulating recessed case 20. It is composed of a layer 26 and a light-shielding cap 10 having a reflecting surface 9 on the side of the translucent sealing layer 26, which is provided above the opening of the insulating concave case 20.

[0003]

However, the conventional chip-type optical coupling device described above has the following drawbacks. (1) Upper electrodes (3-2) of the chip type light emitting device 3 and the light receiving device 4 installed in the recess of the insulating recessed case 20,
Since it takes time to bond (4-2) and the electrodes (3-1) and (4-1) formed on the insulating concave case 20 with the conductive wires 5 and 6, the manufacturing cost is reduced. Bulky. (2) Further, since the conductive wire used is a thin wire for bonding and crimping, the area of the connecting portion is small and it is difficult to obtain high adhesion strength. (3) Further, since wire bonding is performed in the concave portion of the insulating concave case 20, there is a drawback that an electrode for wire bonding must be formed. Therefore, the process for forming the electrode is limited, and the process must be strictly controlled.

In order to eliminate the above-mentioned unsatisfactory point, as shown in FIG. 14, the surroundings of the chip type light emitting element 3 and the light receiving element 4 installed in the concave portion of the insulating concave case 20 are transparent. The non-translucent resin layer 11 which is embedded in the sealing layer 26 and has a wiring conductor (not shown) on the lower surface is provided on the translucent sealing layer 26, and the wiring on the lower surface of the non-translucent resin layer 11 is provided. A method of bump-connecting the conductor and the upper electrodes of the light emitting element 3 and the light receiving element 4 can be considered. However, according to this method, the light emitted upward from the light emitted from the light emitting element 3 is blocked by the non-translucent resin layer 11, so that the light reaching the light receiving element 4 becomes extremely small.

Therefore, according to the present invention, the above-mentioned disadvantages of the optical coupling device having the conventional structure are eliminated, and the conductor wiring and the light emitting element connected to the light emitting element and the light receiving element electrode extending on the bottom surface of the concave portion of the insulating concave case, Easy and strong connection with the electrode of the light receiving element, and its connection processing time is short,
It is an object of the present invention to provide an optical coupling device and a manufacturing method that can reduce the manufacturing cost, have stable performance, and have high reliability.

[0006]

In order to achieve the above object, an optical coupling device according to a first aspect of the present invention is a light emitting element and a light receiving element electrode provided on the bottom surface of a recess of a case having an inner surface formed in a concave shape. An insulative concave case provided with a conductor wiring to be connected to, and a pair of a light emitting element and a light receiving element in which a bottom electrode provided on the bottom surface of the concave portion of the insulative concave case is connected to the conductor wiring and arranged adjacent to each other. A pair of light-emitting element and light-receiving element and a translucent sealing layer arranged so as to fill the bottom of the concave portion of the insulating concave case; and a light-transmitting property of filling the bottom of the concave portion of the insulating concave case. On the sealing layer, a translucent light guide layer having conductor wirings which are respectively connected to the upper electrodes of the light emitting element and the light receiving element in the insulating concave case, and on the opening of the insulating concave case. In addition, a reflective surface is provided on the translucent light guide layer side. The light-shielding cap provided.

In order to manufacture this optical coupling device, as described in claim 2, an insulating concave case having conductor wirings for connecting to the light emitting element and the light receiving element electrode is prepared in advance on the bottom surface of the concave section, and then this insulating case is prepared. First step of arranging a light emitting element and a light receiving element having bumps previously mounted on the upper electrode on the bottom surface of the concave portion of the concave concave case, and a light emitting element on the bottom surface of the concave portion inside the insulating concave case after the first step, and A second step of disposing a translucent light guide plate as a translucent light guide layer provided with conductor wiring connected to the upper electrode of the light receiving element, and a light emitting element through the translucent light guide plate after the second step And a third step of irradiating the upper electrode of the light receiving element with infrared rays to heat and melt the bumps mounted on the upper electrode to connect the conductor wiring on the lower surface of the translucent light guide plate to the upper electrodes of the light emitting element and the light receiving element. And the third
After the step of, a fourth step of injecting a transparent resin into the bottom surface of the concave portion of the insulating concave case to fill the concave portion with a transparent resin layer which is a transparent sealing layer, and After the step, a fifth step of installing a light-shielding body as a light-shielding cap having a reflecting surface on the side of the translucent light guide provided on the opening of the insulating concave case is included.

[0008]

According to the optical coupling device of the present invention, the pair of the light emitting element and the light receiving element, in which the bottom electrode is connected to the conductor wiring and are disposed adjacent to each other, are provided on the bottom surface of the recess of the insulating concave case. A pair of the light emitting element and the light receiving element, and a translucent sealing layer arranged so as to embed the recessed bottom surface of the insulating concave case, and a translucent light embedded in the recessed bottom surface of the insulating concave case. A light-transmitting light guide layer, which is provided on a transparent sealing layer and has conductor wiring connected to the upper electrodes of the light-emitting element and the light-receiving element in the insulating concave case at the bottom, and,
Since the light shield having the reflecting surface on the translucent light guide side is provided on the opening of the insulating concave case, the light emitted from the light emitting element can be efficiently incident on the light receiving element. . According to the manufacturing method of claim 2, the pair of the light emitting element and the light receiving element connected to the light emitting element side conductor wiring and the light receiving element side conductor wiring on the bottom surface of the concave portion of the insulating concave case are provided on the respective upper electrodes. Via the bumps mounted on the light-transmitting encapsulating layer and the conductor wiring under the light-transmitting light guide layer, and the light-emitting element and the conductor wiring on the bottom of the recess of the insulating recessed case also pass through the bumps. Connect electrically. Therefore, a plurality of such pairs of light emitting element and light receiving element can be simultaneously connected through the insulating concave case and the translucent light guide plate as described later. Therefore, the manufacturing cost and the manufacturing time can be significantly reduced as compared with the conventional optical coupling device configured by connecting one by one to the electrode on the bottom surface of the concave portion of the insulating concave case by wire bonding. Further, in the optical coupling device connected by wire bonding, it is difficult to obtain a large adhesion strength at the connection portion because the area of the connection portion between the electrode and the wire is small, but the optical coupling device of the present invention has a bump such as solder. Since the conductor wiring of the translucent light guide layer is connected to the upper electrodes of the light emitting element and the light receiving element via the above, the dimension of the connection conductor can be short, and the connection area is large. Since it is no longer necessary to provide the conductor layer required for wire bonding in the recess of the case, which is necessary in the above case, the recessed case can be manufactured at low cost.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical coupling device and a manufacturing method of the present invention will be described below with reference to the drawings. The optical coupling device 30 of the present embodiment has the configuration shown in FIGS. However, FIG. 1 is a perspective view of the optical coupling device of the present embodiment, FIG. 2A is a sectional view taken along the line AA of FIG. 1, and FIG.
It is a -B sectional view. The optical coupling device 30 of the present embodiment has a concave inner surface, and the light emitting element 1 described later is formed on the bottom surface of the concave portion.
3 and insulating concave case 20 provided with conductor wirings (1-1) and (1-2) connected to the bottom electrode of the light receiving element 14.
And the bottom electrodes on the bottom surface of the concave portion of the insulating concave case 20 are the conductor wirings (1-1) and (1-2), respectively.
A pair of the light emitting element 13 and the light receiving element 14 that are adjacently connected to each other, the light emitting element 13 and the light receiving element 14 of this pair, and the translucent epoxy filled so as to fill the recess of the insulating concave case 20. A translucent sealing layer made of a resin layer 26 and a translucent epoxy resin layer 26 filled in the concave portion of the insulating concave case 20 are provided on the lower portion of the insulating concave case 20. Light-emitting element 13 and light-receiving element 1 of
Translucent guide plate 24 as a translucent light guide layer including conductor wirings (1-3) respectively connected to the upper electrodes of No. 4 of FIG.
And a light-shielding body 10 as a light-shielding cap having a reflecting surface 9 on the light-transmitting guide plate 24 side, which is provided above the opening of the insulating concave case 20.

The optical coupling device of the present embodiment is constructed as described above, and since the upper electrodes of the light receiving and light emitting elements and the conductor wiring are bump-connected, the connecting portion does not break.
It is a highly reliable optical coupling device. Further, the optical coupling device of the present embodiment uses the insulating concave case which is not wire-bonded as the substrate, so that the manufacturing cost is low. Further, the electrodes of a large number of pairs of receiving and emitting elements can be connected to the conductor wiring at once. Further, since the translucent light guide plate on the upper surface of the insulating concave case is transparent, the light emitted from the light emitting element is received by the light receiving element without any interference.

The above-described optical coupling device can be manufactured by the steps described below. 4 to 12 are manufacturing process diagrams of the optical coupling device 30. In the optical coupling device of this embodiment, first, as shown in plan view 4, a plurality of slits 21, 21, 21, ... Are made of an insulating resin material and are parallel to each other in the same direction at equal intervals. Recesses 22 are formed between the adjacent slits 21 and 21. Stepped wall surfaces 22-1, 22- are provided on both left and right side surfaces of the recess 22.
An insulating concave case 20 having No. 1 formed therein is prepared. Then, on the left and right wall surfaces of the concave portion 22 of the insulating concave case 20, a pair of adjacent conductor wirings (1-
1), a plurality of pairs of (1-2) are provided, and conductor wirings (1-1) and (1-2) provided on both left and right wall surfaces are taken along the line CC.
As shown in (a), the bottom surface of the recess is separated by a predetermined distance, and the conductor wirings on the left and right are arranged so as not to be continuous. Further, as shown in the D-D cross-sectional view 5 (b), there is no stepped portion at the end of the recess where the conductor wirings (1-1) and (1-2) are not provided (the traveling direction of the recess). It is an inverted U shape with an open top.

Then, as shown in FIG. 6, a chip type is formed on each pair of conductor wirings (1-1) and (1-2) on the bottom surface of the recesses 22, 22, ... Of the insulating recessed case 20. The bottom electrodes of the light emitting devices 13 and 14 are connected to the conductive adhesive 15 (see FIG.
(See (a)). Bumps 17 (see FIG. 7A) such as solder are previously placed on the upper electrodes of the chip type light emitting element 13 and the light receiving element 14. In addition, the bumps 18 are placed in advance on the stepped wall surface of the concave portion 22 of the insulating concave case 20. After the above working steps are finished, as shown in FIG. 8 and CC sectional view thereof, a translucent light guide plate 24a having a conductor wiring (1-3) on the lower surface and having a thickness of about 0.5 mm is provided. As a translucent light guide layer, it is installed in the recess 22 above the chip type light emitting element 13 and the light receiving element 14. After that, when infrared light is radiated from above the translucent light guide plate 24a and heated, the (solder) pumps 17 and 18 are melted and the conductor wiring (1-3),
(1-3) is connected to the upper electrodes of the chip type light emitting element 13 and the light receiving element 14. The translucent light guide plate 24a is made of a glass substrate or a transparent epoxy resin. The shape of the translucent light guide plate 24a is a spheroidal shape in which the upper surface is spherical or the focal point is located on the light emitting element and the light receiving element as shown in FIG. Alternatively, those having a partial shape thereof may be used. When the translucent light guide plate 24a having such a spherical or ellipsoidal shape is used, the optical coupling ratio between the light receiving element and the light emitting element is improved as compared with the case where the flat plate-shaped translucent light guide plate 24a is used.

Next, as shown in FIG. 8, the resin injection port 23 at the end of the transparent light guide plate 24a (the end position of the transparent light guide plate 24a is displaced from the end position of the recess 22 is arranged. The transparent epoxy resin is injected. Then, the space between the recess 22 and the translucent light guide plate 24a is embedded and sealed by the translucent epoxy resin layer 26a, and then heated and cured at 100 to 180 ° C. in a heating oven (not shown).
Then, the dicing point 27 shown in FIG. 10 (a) is half-diced with a thick blade having a thickness of 0.9 mm,
As shown in FIG. 10B, the surface of the insulating concave case 20 is cut. After that, as shown in FIG. 11, a resin light-shielding body 28 having a reflecting surface 9 formed on the lower surface is bonded by a transparent epoxy resin. The light shield 28 is formed in a male and female shape with the translucent light guide plate 24a so that the gap between the light shield 28 and the lower translucent light guide plate 24a is small. For example, the upper surface of the translucent light guide plate 24a is When it is convex, the lower surface of the light shield 28 is concave. Also,
The reflection surface on the lower surface of the light shield 28 is formed by plating or printing a resin having a high light reflectance. Next, the half-diced portion 27 shown in FIG. 11 is cut with a thin blade having a thickness of 0.3 mm to obtain an optical coupling device 30 having the structure shown in FIGS. 12 and 1. The chip-type optical coupling device obtained by the above manufacturing method has been described as an example in which a large number of chip-type optical coupling devices are manufactured from one insulating concave case 20. An optical coupling device having the same structure can be manufactured by using the insulating concave case 2 of 1. In the method of manufacturing the optical coupling device according to the present embodiment, the bumps are previously mounted on the upper electrodes of the light emitting element and the light receiving element of the pair which are arranged adjacent to the bottom surface of the concave portion of the insulating concave case (first step), After providing a light-transmitting light guide plate having conductive wirings connected to the upper electrodes of the light-emitting element and the light-receiving element on the insulating concave case (second step), infrared rays are passed through the light-transmitting light guide plate. After heating, the bumps previously placed on the upper electrodes of the light-emitting element and the light-receiving element are heated and melted to connect the conductor wiring with these and the upper electrode of the light-emitting element (third step) Since the translucent epoxy resin is injected and filled in the recess of the insulating concave case, the translucent epoxy resin injected naturally fills and seals between the translucent light guide plate and the bottom surface of the recess, Harden. According to the method of manufacturing the optical coupling device of the present embodiment, since the insulating concave case can be used and the substrate having no wire bonding property can be used, the manufacturing cost can be reduced. Further, since a large number of electrodes of the receiving and light emitting chips can be connected to the wiring conductors on the insulating concave case at a time, the manufacturing time can be shortened and the manufacturing cost can be reduced.

[0014]

As is apparent from the above description, according to the present invention, since the optical coupling device is provided with the transparent translucent light guide layer on the upper surface of the light receiving element, the light is emitted from the light emitting element. The emitted light can be incident on the light receiving element with high efficiency. Further, according to the method of manufacturing the optical coupling device of the present invention, since a large number of light emitting elements and electrodes on the light receiving elements can be simultaneously connected in one insulating concave case, the manufacturing time can be shortened and the manufacturing cost can be reduced. . Further, since the insulating concave case used can have no wire bonding property, the substrate cost can be reduced. Further, since the upper electrode on the chip and the conductor wiring under the translucent light guide layer are bump-connected, a highly reliable optical coupling device can be obtained without disconnection at the connection portion.

[Brief description of drawings]

FIG. 1 is a perspective view of an optical coupling device according to an embodiment of the present invention.

2A and 2B are respectively an AA sectional view and a BB sectional view of the optical coupling device shown in FIG.

FIG. 3 is a vertical sectional view showing the structure of an optical coupling device according to another embodiment of the present invention.

FIG. 4 is a plan view showing the structure of an insulating concave case used in an embodiment of the present invention.

5 (a) and 5 (b) are respectively a C-C sectional view and a DD sectional view of the insulating concave case shown in FIG.

FIG. 6 is a plan view showing a state in which a chip-type light emitting element and a light receiving element are mounted in each concave portion of the insulating concave case shown in FIG.

7A and 7B are respectively a C-C sectional view and a DD sectional view of FIG. 6.

FIG. 8 is a plan view showing a state in which a translucent light guide plate is installed on an insulating concave case, and the conductor wiring in the concave portion and the light emitting element and the light receiving element are bump-connected.

FIG. 9 is a CC of the optical coupling device obtained by the process of FIG.
FIG.

10A and 10B are cross-sectional views taken along the line D-D showing the dicing position of the insulating concave case and the translucent light guide plate and the state after dicing, following the step of FIG. 8 respectively. .

11 (a), (b), and (c) are plan views showing a state in which a light-shielding light guide plate is further installed after the step of FIG. 10, a sectional view taken along line CC of FIG. A D sectional view is shown.

FIG. 12 is a cross-sectional view showing a state after dicing separation of each chip type optical coupling device.

13 (a), (b), and (c) are a perspective view, an AA sectional view, and a BB sectional view showing the structure of a conventional optical coupling device, respectively.

FIG. 14 is a vertical sectional view of an improved structure expected from a conventional optical coupling device.

[Explanation of symbols]

 1-1, 1-2, 1-3 Conductor wiring 9 Reflecting surface 10 Light-shielding cap 13 Light emitting element (present invention) 14 Light receiving element (present invention) 17, 18 Bump 20 Insulating concave case 21 Slit 22 Recess 24 Transparent Light-transmitting light guide layer (present invention) 24a Light-transmitting light guide plate (example) 26 Light-transmitting sealing layer (present invention) 26a Light-transmitting epoxy resin layer (working example) 27 Dicing point 28 Light shield 30 Light Coupling device (present invention)

Claims (2)

[Claims] 1. An insulative recessed case having conductor wiring for connecting to a light-emitting element and a light-receiving element electrode on a bottom surface of a recessed portion of an inner surface formed in a recess, and a bottom portion of the recessed bottom surface of the insulative recessed case. A pair of light emitting element and light receiving element whose electrodes are connected to the conductor wiring and are arranged adjacent to each other, and a pair of light emitting element and light receiving element and the translucent light arranged so as to be embedded in the bottom surface of the concave portion of the insulating concave case. Insulating encapsulation layer and a translucent encapsulating layer that fills the bottom of the recess of the insulating concave case, and is connected to the upper electrodes of the light emitting element and the light receiving element in the insulating concave case at the bottom. And a light-shielding cap having a reflective surface on the light-transmissive light guide layer side, which is provided on the opening of the insulating concave case. Optical coupling device. 2. An insulative concave case having conductor wirings connected to a light emitting element and a light receiving element electrode is prepared in advance on the bottom surface of the recess, and a bump is previously mounted on the upper electrode on the bottom surface of the recess of the insulative recess case. The first step of arranging the placed light emitting element and the light receiving element adjacent to each other, and after the first step, the light transmission in which the conductor wiring connecting to the upper electrodes of the light emitting element and the light receiving element on the bottom surface of the recess in the insulating concave case is provided. The second step of disposing the translucent light guide plate as the transmissive light guide layer, and after the second step, the upper electrodes of the light emitting element and the light receiving element are irradiated with infrared rays through the translucent light guide plate and mounted on the upper electrode. A third method for heating and melting the placed bump to connect the conductor wiring on the lower surface of the translucent light guide plate to the upper electrodes of the light emitting element and the light receiving element
And the third step, the fourth step of injecting a transparent resin into the bottom surface of the concave portion of the insulating concave case and filling the concave portion with the transparent resin to form a transparent sealing layer. And a fifth step of, after the fourth step, installing a light shield having a reflecting surface on the side of the translucent light guide layer on the opening of the insulating concave case. 1. The method for manufacturing the optical coupling device according to 1.