JPH05175233A - Manufacture of liquid crystal device - Google Patents

Abstract

PURPOSE:To reduce stray capacitance between electrodes, by forming a region where a channel region layer between regions for forming a source electrode and a drain electrode is formed and a gate electrode by a photolithgraphy method using a light shielding film on a transparent substrate as a mask. CONSTITUTION:By a photolithography method using the same light shielding film 22 as a mask, a gap where a channel region 32c between a source electrode 30 and a drain electrode 31 is formed and a gate electrode 36a on the channel region 32c are formed. Hence the width of the channel region layer 32c between the source electrode 30 and the drain electrode 31 is made nearly equal to the width of the gate electrode 36a, and the layer 32c and the electrode 36a can be so formed that the positions coincide with the upper part of the light shielding film 22. Thereby the overlap of the source electrode 30 and the drain electrode 31, and the gate electrode 36a is remarkably reduced, so that the parasitic capacitance of a TFT element is reduced and the high speed operation of a liquid crystal device is enabled.

Description

Detailed Description of the Invention

(Table of Contents) -Industrial application field-Conventional technology (Figs. 8 to 10) -Problems to be solved by the invention-Means for solving problems-Actions-Examples (Figs. 1 to 7) ) ·The invention's effect

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal device, and more particularly to a method for manufacturing a liquid crystal device (LCD) having a thin film transistor (TFT) as a control element.

[0003]

2. Description of the Related Art FIGS. 8 (a)-(c) and 9 (d)-
10 (f), 10 (g), and 10 (h) are cross-sectional views illustrating a method of manufacturing a conventional TFT active matrix LCD.

First, as shown in FIG. 8A, in a region on a transparent substrate 1 where a channel layer of a thin film transistor (TFT) is to be formed, backlight light for driving a liquid crystal device is applied to this channel layer. The light shielding film 2 is selectively formed so as not to hit. At this time, the width of the light shielding film 2 is formed to be larger than the width of the channel region layer formed in consideration of the alignment margin. Next, the light shielding film 2 is covered to form the insulating film 3. Subsequently, a resist film 4 whose photosensitive reaction is reversed by heat treatment is formed on the insulating film 3. In this conventional example, a resist film 4 whose photosensitive reaction changes from a negative type to a positive type by heat treatment is used. Then
Using the exposure mask 5a, the resist film 4 in the region other than the regions where the pixel electrode, the source electrode and the drain electrode are to be formed
Is selectively exposed (FIG. 8B).

Next, a heat treatment is performed to reverse the photosensitive reaction of the resist film 4 to a positive type (FIG. 8 (c)), and subsequently, another exposure mask 5b is used to form an upper portion of the light shielding film 2.
The resist film 4 in a region other than the strip-shaped region in which the channel layer of the TFT is to be formed is selectively exposed (FIG. 9D).

Next, when the resist film 4 is developed, a resist pattern 4a is formed in a region other than the regions where the pixel electrode, the source electrode and the drain electrode are to be formed and a region where the channel region layer is to be formed (FIG. 9). (E)). Subsequently, an ITO film 6 serving as a pixel electrode / amorphous silicon (n ⁺ a-Si) film 7 doped with phosphorus is formed on the entire surface (FIG. 9F).

Next, when the remaining resist pattern 4a is removed, the ITO film 6 / n ⁺ a-Si in the region other than the region where the pixel electrode, the source electrode and the drain electrode are to be formed and the region where the channel region layer is to be formed. The film 7 is removed together with the resist pattern 4a by lift-off, and the ITO film 6a / n ⁺ is formed in each of the regions where the pixel electrode and the source electrode are to be formed and the drain electrode is to be formed except the region where the channel region layer is to be formed. a-Si film 7a and IT
The O film 6b / n ⁺ a-Si film 7b remains. continue,
A first insulating film to be a part of the semiconductor layer and the gate insulating film is formed on the entire surface.

Then, the first insulating film, the semiconductor layer and the n ⁺
By selectively etching the a-Si films 7a and 7b,
The pixel electrode 10 made of the O film 6a, the source electrode 11 made of the ITO film 6a and the n ⁺ a-Si film 7c connected to the pixel electrode 10, and the source electrode sandwiching the strip-shaped region where the channel layer of the TFT is to be formed. 11 and the drain electrode 12 made of the ITO film 6b and the n ⁺ a-Si film 7d facing each other, and the semiconductor layer 8 and the first semiconductor layer 8 so as to bridge between the source electrode 11 and the drain electrode 12 facing each other.
Of the insulating film 14a is left. Thereby, the source electrode 11
The upper semiconductor layer is the source region layer 8a, the semiconductor layer on the drain electrode 12 is the drain region layer 8b, and the semiconductor layer between the source electrode 11 and the drain electrode 12 is the channel region layer 8c. Is completed.

Next, after forming a drain bus line 13 for connecting the drain electrode 12 of one TFT and the drain electrode 12 of another TFT (not shown) to each other, a second insulating film 14b which becomes a part of the gate insulating film is formed. To form. continue,
After forming the conductor film 15 serving as the gate electrode on the second insulating film 14b, the resist film 16 is formed on the conductor film 15.

Next, the resist film 16 is formed by using an exposure mask.
Of the resist film 1 after selectively exposing (FIG. 10 (g))
6 is developed to form a resist pattern 16a in the region above the channel region layer 8c where the gate electrode is to be formed. At this time, the width of the resist pattern 16a is formed larger than the width of the channel region layer 8c formed in consideration of the alignment margin. Then, the conductor film 15 is selectively etched and removed using the resist pattern 16a as a mask to form a gate electrode 15a (FIG. 10).
(H)). After that, a liquid crystal film (not shown) is formed on the entire surface to complete the liquid crystal device.

[0011]

By the way, according to the above manufacturing method, as shown in FIG. 10G, the resist film 16 is selectively exposed and developed using the exposure mask 5c to form the channel region. When forming the resist pattern 16a serving as a mask for forming the gate electrode 15a above the layer 8c, the width of the resist pattern 16a is made larger than that of the channel region layer 8c in consideration of the alignment margin in the photo process. It is formed in a large size. Therefore, a considerable overlap occurs between the formed gate electrode 15a and the source electrode 11 and the drain electrode 12 which are adjacent to the channel region layer 8c, and as a result, the parasitic capacitance is increased and the speed of the liquid crystal device is increased. There is the problem of being an obstacle.

The present invention was created in view of the problems of the prior art, and it is an object of the present invention to provide a method of manufacturing a liquid crystal device capable of reducing the parasitic capacitance and increasing the speed of the liquid crystal device. To aim.

[0013]

The above-mentioned problems are, firstly, by a step of selectively forming a light-shielding film on a transparent substrate and then forming an insulating film, and a photolithography method using the light-shielding film as a mask. On the insulating film above the light shielding film,
A first pattern forming film is selectively formed in a region where a channel region layer is to be formed between regions where the source electrode and the drain electrode are to be formed, and a photolithography method using a first exposure mask is used. A step of selectively forming a second pattern forming film on a region of the insulating film other than a region where the pixel electrode, the source electrode and the drain electrode are to be formed, and the first and second pattern forming films A step of forming a first conductor film that transmits exposure light on the insulating film via the step of removing the first and second pattern forming films, and lifting off the first conductor film from the first conductor film. A step of forming a pixel electrode, a source electrode, and a drain electrode, and a semiconductor layer and a first gate insulating film are selectively formed so as to bridge the source electrode and the drain electrode. Forming a drain bus line connected to the drain electrode; forming a second gate insulating film and a second conductive film that transmits exposure light on the first gate insulating film in sequence; A third pattern forming film is formed on the second conductor film above the light shielding film by the photolithography method using the light shielding film as a mask, and the gate bus is formed by the photolithography method using the second exposure mask. Forming a fourth pattern forming film on the second conductor film in a region where a line is to be formed, and using the third and fourth pattern forming films as a mask
Etching and removing the conductor film, and forming a gate electrode made of the second conductor film and a gate bus line connected to the gate electrode on the second gate insulating film. Achieved by the manufacturing method, the second
In the step of forming the first and second pattern forming films, a step of forming a first photosensitive film on the insulating film in which a photosensitive reaction type is reversed between a negative type and a positive type by heat treatment. From the surface side opposite to the transparent substrate, above the pixel electrode, the source electrode, the drain electrode, and the light-shielding film, and in the region other than the region where the channel region layer between the source electrode and the drain electrode should be formed After selectively irradiating the first photosensitive film with exposure light, a heat treatment is performed to reverse the photosensitive reaction type of the first photosensitive film, and the transparent substrate side is used as a mask from the transparent film side. A region where the first photosensitive film is selectively irradiated with exposure light, and then the first photosensitive film is developed to form a channel region layer on the insulating film and above the light shielding film. And the pixel electrode, the source electrode, and And a step of forming a first pattern forming film and a second pattern forming film in a region other than a region where a rain electrode is to be formed, respectively, and a method for manufacturing a liquid crystal device according to the first invention, Thirdly, in the step of forming the third and fourth pattern forming films, a second photosensitive layer in which a photosensitive reaction type is reversed between a negative type and a positive type by heat treatment on the second conductive film. Forming a photosensitive film, and selectively exposing the second photosensitive film in the region where the gate bus line is to be formed to exposure light, and then performing heat treatment to form a photosensitive reaction of the second photosensitive film. And irradiating exposure light selectively to a region above the drain bus line, and selectively irradiating exposure light to the second photosensitive film from the transparent substrate side using the light shielding film as a mask. After that, the second The photosensitive film is developed, and the third and fourth regions are formed on the second conductor film, above the light-shielding film, in a region where the gate electrode is to be formed and a region where the gate bus line is to be formed, respectively. And a step of forming a pattern forming film of
Alternatively, the present invention is achieved by the method for manufacturing a liquid crystal device according to the second invention, and fourthly, the drain bus line is a light-shielding conductor film such as an Al film. Achieved by the method of manufacturing a liquid crystal device, and fifth,
The first conductor film is a two-layer conductor film of an ITO film / n ⁺ a-Si film, the second conductor film is an ITO film, and the first and second gate insulating films Is a silicon nitride film. This is achieved by the method for manufacturing a liquid crystal device according to any one of the first to fourth inventions.

[0014]

[Operation] In the method for manufacturing a liquid crystal device of the present invention, a region where a channel region layer is to be formed between regions where a source electrode and a drain electrode are to be formed by a photolithography method using a light shielding film on a transparent substrate as a mask. And the gate electrode is formed by the photolithography method using the same light-shielding film as a mask. Therefore, since the source electrode and the drain electrode on both sides of the channel region layer and the gate electrode are self-aligned, the overlap between them can be minimized to the necessary minimum. This makes it possible to reduce the stray capacitance between the electrodes.

Further, a photolithography method in which a photosensitive film whose photosensitive reaction type is reversed between a negative type and a positive type is used, and exposure from the front surface and exposure through a light shielding film from the transparent substrate side of the back surface are combined, and By the lift-off method, the source electrode, the drain electrode, and the pixel electrode facing each other with the channel region layer self-aligned with the gate electrode sandwiched therebetween are formed by only one formation of the photosensitive film, which simplifies the process. Can be planned.

Further, by using a photolithography method in which a photosensitive film whose photosensitive reaction type is reversed between a negative type and a positive type is used and exposure from the front surface and exposure through a light shielding film from the transparent substrate side on the back surface are combined, Since the gate electrode self-aligned with the channel region layer and the gate bus line connected to this gate electrode are formed by forming the photosensitive film only once, the process can be simplified as described above. You can In addition, even if a light-shielding conductor film such as a drain bus line is included and exposure from the back surface is disturbed, by exposing this part from the front surface in advance, it is only necessary to form the photosensitive film once. Thus, since the gate electrode self-aligned with the channel region layer and the gate bus line connected to this gate electrode are formed, similar to the above,
The process can be simplified.

[0017]

Embodiments of the present invention will now be described with reference to the drawings. 1A to 7Q are diagrams illustrating a method of manufacturing a liquid crystal device (LCD) having a staggered thin film transistor (TFT) as a control element according to an embodiment of the present invention. It should be noted that FIG.
(D), FIG. 3 (f) to FIG. 4 (k), FIG. 6 (n), FIG.
2 (e), FIG. 5 (l), (m), FIG. 6 (o), and FIG. 7 (q) are top views, and FIG.
2D is a sectional view taken along the line, FIG. 6N is a sectional view taken along the line BB of FIG. 6O, and FIG. 7 is a sectional view taken along the line CC of FIG. 7Q.
It shows in (p).

First, as shown in FIG. 1 (a), a transparent substrate 21 made of synthetic quartz is formed so that the channel light of the liquid crystal device does not reach the channel region layer of the TFT.
A light shielding film 22 made of a chromium (Cr) film having a film thickness of about 600 Å is selectively formed in a region including a region where a channel region layer of a thin film transistor (TFT) is to be formed. At this time, the width of the light shielding film 22 is formed to be substantially the same as the width of the formed channel region layer. Next, the insulating film 2 which covers the light shielding film 22 and is made of a SiO ₂ film having a thickness of about 5000Å
3 is formed.

Next, after a resist film (first photosensitive film) 24 whose photosensitive reaction type is changed from a negative type to a positive type is formed on the insulating film 23 by heat treatment, a pixel electrode, a source electrode, a drain electrode and a source electrode are formed. The resist film 24 in the region other than the region where the channel region layer is to be formed between the drain electrode and the drain electrode is selectively exposed using the exposure mask (first exposure mask) 25 (FIG. 1B).

Next, heat treatment is performed under the conditions of a temperature of 120 ° C. and a time of 10 minutes to change the photosensitive reaction type of the resist film 24 from the negative type to the positive type (FIG. 1 (c)). Next, using the light-shielding film 22 as a mask, the resist film 24 in the strip-shaped region in which the channel region layer of the TFT is to be formed above the light-shielding film 22 from the transparent substrate 21 side is selectively exposed. At this time, the width of the non-exposed portion 26c on the light-shielding film 22 is made narrower than the width of the light-shielding film 22 by slightly exposing the light-shielding film 22 (FIGS. 2D and 2E).

Next, when the resist film 24 is developed, a region 26b irradiated with the exposure light as a negative type resist film.
Then, the resist film in the region 26c which is not exposed to the exposure light remains as a positive type resist film. That is, a resist pattern (first pattern forming film) is formed in each of a region between the source electrode and the drain electrode where a channel region layer is to be formed and a region other than the region where the pixel electrode, the source electrode and the drain electrode are to be formed. 24a and a resist pattern (second pattern forming film) 24b are formed (FIG. 3).
(F)).

Then, an ITO film 27 having a film thickness of about 500 Å to be a pixel electrode is doped with phosphorus by an n-type a-Si film (n ⁺ a-Si film) having a film thickness of about 300 Å by sputtering.
28 is sequentially formed on the entire surface by the plasma CVD method. The two conductor films of the ITO film 27 and the n ⁺ a-Si film 28 form a first conductor film 39 (FIG. 3G).

Next, the remaining resist patterns 24a, 24
When b is removed, the ITO film 27 / n ⁺ a-Si other than the region where the pixel electrode, the source electrode and the drain electrode are to be formed is formed.
The film 28 is removed by lift-off together with the resist patterns 24a and 24b, so that the ITO film 27a / n ⁺ a-Si film 28a is formed.
The two-layered conductive film remains in the regions where the pixel electrode and the source electrode are to be formed, and the ITO film 27b / n ⁺ a-Si
The two-layer conductor film of the film 28b remains in the region where the drain electrode is to be formed (FIG. 3 (h)).

Then, a-Si having a film thickness of about 200 Å is formed on the entire surface.
An insulating film made of a SiN film having a film thickness of about 500Å to be a part of the gate insulating film and a semiconductor layer made of is sequentially formed by the plasma CVD method. Then, an insulating film, a semiconductor layer, and n
^{The +} a-Si films 28a and 28b are selectively etched, and I
The pixel electrode 29 made of the TO film 27a, the source electrode 30 made of the ITO film 27a / n ⁺ a-Si film 28c connected to the pixel electrode 29, and the band-shaped region where the channel region layer of the TFT is to be formed are sandwiched between the sources. ITO film 27 facing the electrode 30
The drain electrode 31 made of the b / n ⁺ a-Si film 28d is formed, and the semiconductor layer 32 is formed so as to bridge between the source electrode 30 and the drain electrode 31 facing each other.
The first gate insulating film 33 remains. As a result, the semiconductor layer on the source electrode 30 becomes the source region layer 32a, the semiconductor layer on the drain electrode 31 becomes the drain region layer 32b, and the semiconductor layer between the source electrode 30 and the drain electrode 31 becomes the channel region layer 32c. The completed TFT is completed.

Next, after forming a drain bus line 34 for connecting the drain electrode 31 of one TFT and the drain electrode of another TFT (not shown) to each other (FIG. 4 (i)), a part of the gate insulating film is formed. A second gate insulating film 35 made of a SiN film having a thickness of about 3000 Å is formed.

Then, on the second gate insulating film 35, an IT having a film thickness of about 3000 Å to be a gate electrode and a gate bus line is formed.
An O film (second conductor film) 36 was formed (FIG. 4 (j)).
After that, a resist film (second photosensitive film) 37 in which the type of photosensitive reaction is changed from negative type to positive type by heating is formed on the ITO film 36 (FIG. 4 (k)).

Next, the resist film 37 in the region where the gate bus line is to be formed is selectively exposed using an exposure mask (second exposure mask) not shown (FIG. 5 (l)). Then, heat treatment is performed at a temperature of 120 ° C. for 10 minutes to change the negative type resist film 37 into a positive type resist film 37. Here, when the exposure light is normally irradiated from the transparent substrate 21 side in the next step, the resist film 37 above the drain bus line 34 is not exposed to the exposure light because it becomes a shadow of the drain bus line 34. Three
When 7 is developed, the resist film 37 remains in this portion. Therefore, next, the resist film 37 above the drain bus line 34 is previously exposed from the front surface side using an exposure mask (not shown) so that it can be removed by development (FIG. 5 (m)).

Next, the resist film 37 is selectively exposed from the transparent substrate 21 side using the light shielding film 22 as a mask (FIG. 6).
After (n) and (o), when the resist film 24 is developed, the resist 38 in the area 38b exposed to the exposure light as the negative type resist film 37 and the area 38e not exposed to the exposure light as the positive type resist film 37. The film remains. That is, a resist pattern (third pattern forming film) 37a having substantially the same width as the width of the channel region layer 32c is formed in the region above the channel region layer 32c where the gate electrode is to be formed, and the gate bus line is formed. A resist pattern (fourth pattern forming film) 37b is formed in the region where the pattern is to be formed.

Then, the ITO film 36 is selectively etched and removed by using the resist patterns 37a and 37b as a mask to form a gate electrode 36a and a gate bus line 36b made of the ITO film (FIGS. 7 (p) and 7 (q)). ). afterwards,
A liquid crystal device is completed by forming a liquid crystal film (not shown) on the entire surface.

As described above, according to the embodiment of the present invention,
A gap where the channel region layer 32c is formed between the source electrode 30 and the drain electrode 31 and the channel region layer are formed by the photolithography method using the same light shielding film 22 as a mask.
The gate electrode 36a is formed on 32c. Therefore, the width of the channel region layer 32c between the source electrode 30 and the drain electrode 31 and the width of the gate electrode 36a are substantially equal to each other, and both can be formed so as to be aligned above the light shielding film 22. Therefore, the overlap between the source electrode 30, the drain electrode 31, and the gate electrode 36a is extremely small, so that the parasitic capacitance of the TFT element can be reduced and the speed of the liquid crystal device can be increased.

Further, although the exposure light is selectively irradiated from the surface opposite to the transparent substrate 21 using the exposure mask, the exposure light is selectively irradiated by using a device that can restrict the exposure light without using the exposure mask. May be irradiated.

[0032]

As described above, according to the embodiments of the present invention, the channel region layer between the regions where the source electrode and the drain electrode are to be formed by the photolithography method using the light shielding film on the transparent substrate as a mask. The gate electrode is formed by the photolithography method using the same light-shielding film as a mask. Therefore, since the source electrode and the drain electrode and the gate electrode on both sides of the channel region layer are self-aligned, the overlap between the source electrode and the drain electrode and the gate electrode can be extremely reduced. As a result, the stray capacitance between the electrodes can be reduced, and thus the speed of the liquid crystal device can be increased.

[Brief description of drawings]

FIG. 1 is a diagram (No. 1) explaining a method for manufacturing a TFT active matrix LCD according to an embodiment of the present invention.

FIG. 2 is a diagram (No. 2) explaining the manufacturing method of the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 3 is a diagram (No. 3) explaining the method of manufacturing the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 4 is a view (No. 4) explaining the method of manufacturing the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 5 is a view (No. 5) explaining the method of manufacturing the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 6 is a view (No. 6) explaining the method for manufacturing the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 7 is a view (No. 7) explaining the method of manufacturing the TFT active matrix LCD according to the embodiment of the present invention.

FIG. 8 is a cross-sectional view (No. 1) for explaining the method for manufacturing the conventional TFT active matrix LCD.

FIG. 9 is a sectional view (No. 2) for explaining the method for manufacturing the conventional TFT active matrix LCD.

FIG. 10 is a conventional TFT active matrix LCD.
FIG. 7 is a cross-sectional view (3) explaining the manufacturing method of.

[Explanation of symbols]

 21 transparent substrate, 22 light-shielding film, 23 insulating film, 24 resist film (first photosensitive film), 24a resist pattern (first pattern forming film), 24b resist pattern (second pattern forming film), 25 exposure Mask (first exposure mask), 26a, 26c, 38a, 38c, 38e Unexposed part, 26b, 26d, 38b, 38d Exposed part, 27, 27a, 27b ITO film, 28, 28a, 28b, 28c, 28d a -Si film, 29 pixel electrode, 30 source electrode, 31 drain electrode, 32 semiconductor layer, 32a source region layer, 32b drain region layer, 32c channel region layer, 33 first gate insulating film, 34 drain bus line, 35th 2, gate insulating film, 36 ITO film (second conductor film), 37 resist film (second photosensitive film), 37a resist pattern (third pattern forming film), 37b resist Pattern (fourth pattern forming film), 39 first conductor film.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 27/12 A 8728-4M

Claims (5)

[Claims] 1. A step of selectively forming a light-shielding film on a transparent substrate and then forming an insulating film, and a photolithography method using the light-shielding film as a mask to form an insulating film above the light-shielding film. And selectively form a first pattern forming film in a region where a channel region layer is to be formed between regions where the source electrode and the drain electrode are to be formed, and a photolithography method using a first exposure mask. Thereby selectively forming a second pattern forming film on the insulating film in a region other than the region where the pixel electrode, the source electrode and the drain electrode are to be formed, and the first and second patterns. Forming a first conductor film that transmits exposure light on the insulating film through a forming film; removing the first and second pattern forming films, and lifting off the first conductor. From the membrane A step of forming a pixel electrode, a source electrode and a drain electrode, and a drain connecting the drain electrode while forming a semiconductor layer and a first gate insulating film selectively so as to bridge the source electrode and the drain electrode. A step of forming a bus line, a step of sequentially forming a second gate insulating film and a second conductor film which transmits exposure light on the first gate insulating film, and the light shielding film as a mask A region where a gate bus line is to be formed by a photolithography method using a second exposure mask while forming a third pattern forming film on the second conductor film above the light shielding film by a photolithography method. Forming a fourth pattern forming film on the second conductor film, and using the third and fourth pattern forming films as a mask to etch the second conductor film. And a step of forming a gate electrode made of the second conductor film and a gate bus line connected to the gate electrode on the second gate insulating film by etching and removing. 2. In the step of forming the first and second pattern forming films, a first photosensitive film whose photosensitive reaction type is reversed between a negative type and a positive type by heat treatment is formed on the insulating film. Forming step, and from the surface side opposite to the transparent substrate, above the pixel electrode, the source electrode, the drain electrode, and the light-shielding film, except the region where the channel region layer between the source electrode and the drain electrode is to be formed. And selectively irradiating the first photosensitive film in the region of 1 with exposure light, and then performing heat treatment to reverse the photosensitive reaction type of the first photosensitive film, and the transparent substrate using the light shielding film as a mask. The first from the side
After selectively irradiating the photosensitive film with exposure light, the first photosensitive film is developed to form a channel region layer on the insulating film above the light-shielding film, 2. The method of manufacturing a liquid crystal device according to claim 1, further comprising: forming a first pattern forming film and a second pattern forming film in a region other than a region where the pixel electrode, the source electrode and the drain electrode are to be formed, respectively. Method. 3. In the step of forming the third and fourth pattern forming films, a second type in which a photosensitive reaction type is reversed between a negative type and a positive type by heat treatment on the second conductive film. Forming a photosensitive film, and irradiating the second photosensitive film in the region where the gate bus line is to be formed with exposure light selectively, and then subjecting it to heat treatment to subject the second photosensitive film to a photosensitive reaction. A step of reversing the form, and selectively exposing the region above the drain bus line with exposure light, and selectively exposing the second photosensitive film from the transparent substrate side with the light shielding film as a mask. After the irradiation, the second photosensitive film is developed to form a region on the second conductor film above the light shielding film where a gate electrode is to be formed and the gate bus line. 3rd and 4th pattern in each area 3. A method of manufacturing a liquid crystal device according to claim 1, further comprising the step of forming a screen forming film. 4. The method of manufacturing a liquid crystal device according to claim 3, wherein the drain bus line is a light-shielding conductor film such as an Al film. 5. The first conductor film is an ITO film / n ⁺ a
2. A two-layer conductor film of a -Si film, the second conductor film is an ITO film, and the first and second gate insulating films are silicon nitride films. A method for manufacturing a liquid crystal device according to claim 2, claim 3 or claim 4.