JPS60180171A - Insulated gate type field-effect semiconductor device and trimming method - Google Patents

Abstract

PURPOSE:To enable trimming after forming a gate electrode by shaping a conductive film consisting of an oxide or a nitride mainly comprising tin or indium as a gate electrode material on a gate insulator. CONSTITUTION:A first conductive film 2, a first non-singular crystal semiconductor 3, a first insulator 4 and a third semiconductor 5 are laminated on an insulating substrate 1. A second conductive film 6 consisting of ITO, etc. and a second insulator 7 are laminated to the upper surface of the third semiconductor. An intrinsic or P<-> non-singular crystal semiconductor constituting a channel forming region is laminated as a third semiconductor 24 while covering such laminates 13, 14, 15 a conductor 16 and an insulator 17. A silicon nitride film 25 and a third conductive film 26 are formed. The conductive film 26 constituting a gate electrode is formed in a conductive film composed of an oxide or a nitride mainly comprising tin or indium and a conductive film having heat resistance and sublimating properties.

Description

Detailed Description of the Invention The present invention has a structure in which a gate electrode of an insulated gay I-type semiconductor device (hereinafter referred to as IGF) can be trimmed after formation, and the gate electrode is made mainly of tin or indium. (2) The purpose is to provide a conductive film using an oxide or nitride.

The present invention provides a trimmable IGF that includes a first conductive electrode, a first semiconductor, a first insulator, a second semiconductor, a second conductive electrode, and a second conductive electrode on a transparent insulating substrate. A channel formation region is formed by a third semiconductor formed on the first insulator on the side of the stacked body consisting of six layers of insulators, and a gate of silicon nitride or silicon carbide is formed on this formation region. This uses an IGF having an insulating film and a gate electrode formed of an oxide or nitride conductive film containing tin or indium as a main component on the insulating film.

By applying the IGF of the present invention, a solid-state display device connected to each picture element can be provided.

An object of the present invention is to provide a composite semiconductor device having such a matrix structure on a substrate and apply it to a display device such as a liquid crystal display type or an electrochromic display type that is a solid state display device.

This liquid crystal display or electrochromic display element can be represented by a capacitor (hereinafter referred to as C) as its equivalent circuit. For this purpose, IGF and (3)C are arranged in a 2×2 matrix, for example, as shown in FIG.

In FIG. 1, each address of the matrix constitutes a picture element of H[lil by two IGFs (10), (10') forming a pair and C (70) as a display section.

These are connected to the bit line as columns (leads in the Y direction>(51), <52), and on the other hand, rows (part X53 in the X direction) and (54) (word lines) are connected as gate branches. It is something that

Then, (if arranged, (51), <5 meetings) becomes 11'', (
If 52 pieces (54) are "0", ycp (10),
<10') are both turned on, and IGFs at other addresses are turned off. Then, by selectively turning on arbitrary bit lines and word lines one by one or as one row or column, the display section represented by the electrically equivalent element C (70) can be selectively turned on. can.

In the present invention, when the active picture elements in a solid-state display device are, for example, 640 x 525, the IG of all the picture elements is
It is completely impossible to operate F normally considering its product yield. Therefore, (4) in the present invention, if the gate of one IGI' of a pair of IGFs is damaged (short-circuited), the damaged IGF is laser trimmed from the lead in the X direction (hereinafter referred to as LT). Each pixel is equipped with a so-called redundant element, which makes it a good product by separating and removing it by applying an electric pulse, or by vaporizing and removing one side of the electrode that is short-circuited by applying an electric pulse. . For this purpose, the present invention uses a conductive film of an oxide or nitride whose main component is tin or indium, which has sublimation property, for the gate electrode of this IGF. It is characterized by being made of a small conductive film.

FIG. 2 shows a longitudinal cross-sectional view of a stacked IGF for carrying out the present invention and its manufacturing process.

This figure shows a manufacturing example in which two IGFs are used to drive display picture elements and are manufactured along one stacked body, but the same is true when a plurality of IGFs are manufactured on the same substrate.

In the drawings, an insulating substrate (1) such as a quartz glass (5) or a borosilicate glass substrate or an organic film is shown with a first layer on it.
A conductive film (2) was provided as the lower electrode and one electrode of the picture element. In this embodiment, a transparent conductive film whose main component is tin oxide doped with fluorine is formed to a thickness of 0.3 μm. Selective etching was performed on this using the first mask (3).

Furthermore, a first non-single crystal semiconductor (3) (hereinafter simply referred to as 31) having a conductivity type of P or N type is placed on the upper surface of the 100
~3000 people, first insulator (4〉hereinafter simply referred to as S2><0.3 to 3μ)4 third semiconductor (5) having the same conductivity type as the first semiconductor (hereinafter simply referred to as S3)〈 0.
1 to 0.5μ> were laminated (stacked or referred to as S). This lamination provided a NIN/PIP structure (I is an insulator).

On top of this is ITO (indium tin oxide).

MoS+, * Tl5IL + WStL+ W+
A second conductive film (6〉 (hereinafter also referred to as S5) of a heat-resistant metal whose main component is Ti + Mo + Cr, here a metal whose main component is chromium (500 to 30
00 people), and then put aluminum on the top surface.
．． A stack of 5 to 2μ, for example 1μ, was used (6). Furthermore, there is a second layer on the upper layer that is effective as an insulator between the eyebrows.
The insulator (7) (hereinafter simply referred to as 55) was laminated to a thickness of 0.5 to 5 μm, for example, 2 μm. This insulator was an organic resin such as PIQ.

The N and P layers of the first and third semiconductors are N'N or P"
It was effective to reduce the contact resistance between P or N and the first and second electrodes by using N'NINN'' as P and P''PIPP' (I is an insulator).

In this way, the first conductor (12), the first semiconductor (13), the first insulator (14), and the third semiconductor (
15), second conductor (16) and second insulator (17)
) was obtained by forming a laminate (60) using a mask (2).

Here, plasma gas phase etch, e.g. liver gas or CF,
+ oL mixed gas, 0.1 to 0.5 torr,
The etching speed was set at 30W and 500 people/min.

After this, these laminates SL (13), 52 (14)
, S3 (15).

A third layer is made of an intrinsic or P-type non-single crystal semiconductor that covers the conductor (16) and the insulator (17) and forms the channel formation region.
It was laminated as a semiconductor (24). This third (7) semiconductor (24) is prepared by silane glow discharge method (
PCVD method), photoCVD method, LT CVD method (IIOM
Temperatures from room temperature to 500°C, such as 200°C and 0.1 torr in the pcVD method.
, 30 W, and 13.56 Mllz, and is a non-single-crystal silicon semiconductor with an amorphous, semi-amorphous, or polycrystalline structure doped with hydrogen or fluorine. I am using it. The present invention focuses on amorphous or semi-amorphous semiconductors.

Furthermore, in the same reactor, a silicon nitride film (25) was heated with mercury using silane (disilane is also acceptable) and ammonia using the photo-CVD method, without exposing the third semiconductor surface to the atmosphere. The thickness is 300~300 mm.
It was set at 2,000 people.

This insulating film may be immersed in a nitrogen or ammonia atmosphere activated by electromagnetic energy at a frequency of 13.56 MI (z to 2.45 Gtlz) at 100 to 400° C. to form silicon nitride in a solid-vapor phase reaction.

In addition, DMS (I
f, 5i (8) (CI, ), ), MMS (11, Si (CTo
)) may be used to form silicon carbide (25).

Thus, in the vicinity of the S2 (14) side as shown in FIG. 2(B), a channel forming region (9), <9') and an insulator as a gate insulator (25) were formed thereon.

The third semiconductor (24) forms a diode junction with Sl and S3.

In FIG. 2(B), a third conductive film (18) is then formed to cover this laminate to a thickness of 30 to 1,500, for example, 5.
00 people were formed.

The conductive film (26) constituting this gate electrode was an oxide or nitride conductive film containing tin or indium as a main component, and was a heat-resistant and sublimable conductive film.

As a conductive film of an oxide or nitride containing tin or indium as a main component, for example, sublimable tin oxide or ITO (indium tin oxide) was fabricated by electron beam evaporation. Aluminum is generally used as a conductor. This aluminum has a melting point of 65B, 8°C, and a thermal conductivity of 0.487ca1. cm-1,5ec-'(9) deg'', specific resistance 2.75 x 10-'Ocm
It is. However, due to its high thermal conductivity and oxidizing properties,
When laser pulse light is irradiated, the thermal energy is propagated laterally, and the highly heated parts cannot be vaporized.

Furthermore, it undergoes an oxidation reaction with the gate insulator and the atmosphere, leaving conductive aluminum oxide. On the other hand, conductive films of oxides or nitrides whose main component is tin or indium are sublimable, so they do not appear in a molten state, but are directly vaporized by heating and have already been oxidized or nitrided, so they cannot be used as electrodes. The material itself should not react with the gate insulator, or heavy indium or tin metal may diffuse into the insulator, causing a short circuit with the semiconductor in the channel formation region or the source and drain electrodes. It turned out to be a very special material.

Furthermore, in order to make a lead connected to the gate electrode, aluminum is vacuum evaporated to a thickness of 0.5 to 3 μm, for example, 1.5 μm, on the top surface of the conductive film of oxide or nitride containing tin or indium as the main component. The sheets were laminated according to the method (10), and the sheet resistance was set to 0.1 Ω/hole or less.

After this, a resist is formed on this upper surface, and a third mask ■
The word line (X direction) shown in FIG.
51) Etched the aluminum for (lead wire X53). Furthermore, gate electrodes (19) and (19') were formed by etching using the fourth mask (2).

Thus, Figure 3(C) was obtained. Of course the lead wire (53
) and a gate electrode, this ■ mask is ■
is processed in the same way.

Thus, S4 (24) with source or drain 51 (13), channel forming region (9), <9'>
, a drain or a source is formed by 53 (15), and a gate insulator (18) is formed on the side surface of the channel formation region.
), <1.8') on its outer surface with a gate electrode (1
9), <19')
(10), <10').

When attempting to investigate the operating characteristics of these two IGFs,
For example, assume that one of the gate electrodes and the source (11) are short-circuited, or the drain (11) is short-circuited. Alternatively, since the gate electrode (19), <19'), the conductive electrode (36) constituting the picture element, and the element electrode (12) are one electrode of the capacitor, the charge accumulated for a certain period of time during the drive operation must continue to be held, and if the show] is occurring, this charge holding is impossible.

In such a faulty IGF, the current is 10 nA or more between the X direction lead and the Y direction lead of the drive punch of the IGF (each IGF
GF flows (with a channel length of 1μ and a channel length of 2mm). To detect a defective cell in one of these two IGFs, the channel forming region is irradiated with light (500 nm or less) from the substrate side through a conductive film of oxide or nitride whose main component is tin or indium. (preferably a wavelength of That is, if it is a good product, it will be greatly affected by the photocurrent, but if it is a defective product, it can be determined because there is almost no change. Furthermore, for defective IGFs, a Q-switch is added to the excimer laser (12) laser (wavelength 250-500 nm) from above (
(average output: 0.8 - IL pulse is performed once to several times), and the gate electrode handled by the X-direction lead was trimmed and electrically isolated.

The laser light may be a YAG laser (wavelength: 1.06μ).

However, since only the gate electrode is selectively removed, the optical E
Shorter wavelength laser light with g of 3 eV or more (wavelength 250
~500 nm) had a significant effect on gate electrode removal. In addition, such short wavelength light has a pulse duration of 5 to 30 ns, which is shorter than the 60 to 90 ns of a YAG laser, and therefore has less lateral conductivity of heat, making it possible to further promote sublimation trimming. .

Of course, in the present invention, the leads in the X direction have a sheet resistance of 0.1 Ω/hole or less and a thickness of 0.5 μ or more, since the main wiring is made of aluminum.

However, on the other hand, the gate electrode of the IGF branched from this lead is formed of a conductive film (sheet resistance 5 to 500 Ω/hole) of oxide or nitride mainly composed of tin or indium, and has a thin thickness of, for example, 30 (13). ~1000 people) For example, a major feature is that it uses sublimable conductors of 500 people.

In other words, if a metal with such sublimation property is used as a gate electrode and its thickness is thin, a pulse voltage is applied between the lead in the X direction and the lead in the Y direction.
A voltage that is high enough not to damage the good gate insulator between the leads in both directions (e.g. 1μ during pulse, voltage 30V)
I added it. Then, only the gate portion of this short-circuited defective IGF generated heat, making it possible to partially sublimate and remove the electrode material thereon.

Of course, as part of the trimming process, in order to investigate the defective IGF, an electric pulse is first applied to damage the gate electrode, and then the gate electrode is inspected visually or with a computer-aided detector (a CCD camera connected to a microcomputer). Needless to say, it is also effective to detect the defective IGF using a device that detects the defective IGF and trim the gate electrode from the lead using a laser beam to make it inoperable.

Furthermore, in the present invention, after trimming (14), ultrasonic cleaning is performed using acetone, Freon solution, etc.
It is effective to remove scattered objects by laser irradiation.

FIG. 3 is a plan view of a portion of the solid-state display device of the present invention shown in FIG. 1 using the IGP shown in FIG. 2.

Figure 3 (A) shows (1, 1), <1.2), (
2,1).

Corresponding to address (2, 2), especially I of address (L2 >)
It is a top view of GF. Furthermore, Fig. 4 (B) is similar to Fig. 3 (A
) is a longitudinal sectional view taken along line BB'. Also, A in Figure 3 (A)
-A' corresponds to the longitudinal cross-sectional view of FIG. 2(C).

The electrode extending from the lower electrode (12) of this IGF (provided on the lower side in Fig. 3) is connected to a liquid crystal (capacitor) (70) composed of picture elements. . The other is provided as a ground electrode (32) for the liquid crystal (70).

In FIG. 3, the gate electrode (19) provided along the laminate (60) (<19') is connected to the laminate (60).
The lead (53) in the X direction is provided perpendicular to the lead (53).
). A second conductive IJ provided (15) inside the laminate (60)! 1 (51) is configured as a lead wiring in the Y direction. In this way, it was possible to have a matrix configuration in the X and Y directions and an ITr/pixel structure.

Furthermore, in order to operate these picture elements at high frequencies, IGF
The frequency characteristics of the IGF of the present invention are extremely important.
is Vpb -8V, Vpb -8V, cutoff frequency 10MHz or more (19.5MHz XN channel IG
F>. V, -O,S~3v
This became possible by controlling the concentration of impurities added to 54 (25).

If one of the gate electrodes of a pair of IGFs is short-circuited like this, a laser beam, such as a Q-switched vAG laser beam, is irradiated from above to sublimate and vaporize the gate electrode, thereby damaging the panel. We were able to improve the overall yield from the previous state of only 3% to over 40% (defective picture elements are considered good if there are 5 or fewer defective picture elements). In the practice of the present invention, the laser light (here a YAG laser with a wavelength of 1.06μ was used) had a (16) diameter of 10 to 30μ. For this reason, since the gate electrodes of the pair of IGFs of the present invention are separated by 30 μm from each other, the picture element on the short-circuited side of one of the IGFs could be removed without causing any trouble to the other IGFs forming the pair.

Furthermore, four masks are sufficient for manufacturing, and the channel length is 0.
In addition to being able to make it very short to 2 to 1μ, it was also possible to have it.

Furthermore, after these trimming processes, the polyimide resin for overcoating of this IGF <zf> c:
More, picture element. In addition, this spacer was used to make the peripheral area of the picture element black (non-reflective) and used as a blasomatrix. By creating a blank matrix, we were able to improve the contrast of this picture element. Furthermore (31
) is the display body, for example GH (guest host)
Fill liquid crystal such as a mold, and convert this picture element into IGF (10), <
Control was performed by turning on (10') and off (17).

In the present invention, 2 which has been subjected to alignment treatment for liquid crystal (31)
The distance between the two electrodes (30>, <32) is 1 to 10μ, for example, GH type liquid crystal is injected into the gap, and in addition, the counter substrate (
By embedding red, green, and yellow filters in 1*), it is possible to display this display in color.

Then, the three elements of red, green, and yellow may be arranged alternately.

In the present invention, it is effective to use a semiconductor as the second stacked body and use the periphery of this side as a channel formation region. However, although such a structure has the advantage that there is no step of forming a third semiconductor, in such a case, the surface of this semiconductor is exposed to an etching atmosphere, so that the interface state density is lower than that of the method using the third semiconductor described above. It has the disadvantage that it is larger than the other IGFs, and variations occur between the IGFs.

In addition, in the present invention, a conductive oxide or a conductive film is coated with a metal mainly composed of chromium (18) having sublimation property on a conductive film of an oxide or nitride mainly composed of tin or indium on the gate insulating film. It is effective to form the material with a thickness thinner than that of the nitride for protection and to improve its mechanical resistance against subsequent handling.

In the present invention, the oxide conductive film containing tin or indium as a main component is tin oxide (SnO or SnO>,
ITO is deposited by electron beam evaporation, and the nitride conductive film is deposited by the so-called ion blating method, in which metal tin or indium is evaporated and the metal tin or indium is nitrided with ammonia, which is turned into plasma while in flight. Tin nitride, indium nitride, or indium tin nitride was prepared. Furthermore, by using SnO as a starting material and creating an ammonia plasma atmosphere, a tin oxynitride or an indium compound could be produced.

[Brief explanation of the drawing]

FIG. 1 shows an equivalent circuit of a solid-state display device according to the present invention having a matrix structure in which an insulated semiconductor device and a capacitor are used as picture elements. (19) FIG. 2 ('A), <B), <c) is a longitudinal sectional view showing the steps of the stacked insulated gate semiconductor device of the present invention. FIGS. 3(A) and 3(B) are longitudinal sectional views of a solid-state display device showing a flat display in which the stacked insulated gate semiconductor device of the present invention, a capacitor, and a display portion are integrated. Patent applicant (20) Certain 1■ Tsume 2 (2)

Claims (1)

[Claims] 1. A semiconductor provided on a substrate or a conductive electrode on the substrate, and an oxide or indium mainly containing tin or indium as a gate electrode material on a gate insulator on the semiconductor. An insulated gate field effect semiconductor device characterized by being provided with a nitride conductive film. 2. In claim 1, an insulated gate semiconductor device includes a first semiconductor on a first electrode, a first insulator,
It has a laminate in which a second semiconductor, a second conductive film, and a glabellar insulator are laminated in approximately the same shape, the first and second semiconductors constitute a drain and a source, and a side of the laminate is provided. A channel forming region is formed by a third semiconductor adjacent to the part, and a gate insulating film and a gate electrode of an oxide or nitride conductive film containing tin or indium (1) as a main component are formed on the semiconductor. An insulated gate field effect semiconductor device, characterized in that the insulated gate field effect semiconductor device is provided on a side surface of the laminate. 3. Irradiate a defective semiconductor device with laser light in an insulated gate field effect semiconductor device in which a gate electrode of an oxide or nitride conductive film containing tin or indium as a main component is connected to a lead. The semiconductor device is transformed into a non-defective product by electrically separating the defective portion of the gate electrode from the lead connected to the gate electrode, or by selectively removing a portion of the defective region within the gate electrode. A method for trimming an insulated gate field effect semiconductor device, characterized in that: