WO2000014600A1

WO2000014600A1 - Active matrix liquid crystal device and method for producing the same

Info

Publication number: WO2000014600A1
Application number: PCT/JP1999/004606
Authority: WO
Inventors: Hiraaki Yonekura; Shinichiro Ishihara
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 1998-09-04
Filing date: 1999-08-26
Publication date: 2000-03-16
Also published as: TW536647B; JP2000081638A; CN1317106A; KR20010079729A

Abstract

A pattern formation for partly removing a second insulating film (6) to make an opening so as to lay a scanning signal wiring (2) and a video signal wiring (5) and a pattern formation for partly removing a first insulating film (3) to make an opening so as to carry out layer conversion of the layer for the scanning signal wiring (2) and the layer for the video signal wiring (5) are simultaneously conducted. Hence the number of cycles in the photolithography processing of a TFT array process is five. The layer for the scanning signal wiring (2) and the layer for the video signal wiring (5) are electrically interconnected through the layer for a pixel electrode (7).

Description

Harm

Active matrix liquid crystal display device and method of manufacturing the same

Technical field

The present invention relates to an active matrix type liquid crystal display device that displays an image by driving a liquid crystal by a switching element, and a method of manufacturing the same. Background art

In recent years, display devices that use liquid crystal for image display have been widely used because they have features that are not thin and light, and that have low power consumption, unlike conventional displays that use a CRT or the like. Among them, an active matrix type liquid crystal display device (hereinafter, referred to as an AMT LCD device) has a switching element composed of a thin film transistor (hereinafter, referred to as TFT) for each pixel arranged in a matrix, and the switching element. Drives the liquid crystal to display an image. The AMT LCD device is used for a display of a notebook computer navigation system and the like, since it can provide a clear image display with little crosstalk, and has been rapidly used in recent years. Hereinafter, an example of a conventional AMT LCD device will be described with reference to the drawings. FIG. 2 is a cross-sectional view of an array portion having a FT of a conventional AM T 1_〇0 device. As shown in Fig. 2, the conventional AMT LCD device

(a) a glass substrate 1 which is an insulating transparent substrate in a TFT array portion,

(b) a scanning signal wiring 2 which also serves as a gate electrode of a TFT arranged in a matrix on a glass substrate 1 and supplies a scanning signal to the gate electrode of the TFT; (c) a first insulating film forming a first insulating layer laminated on the scanning signal wiring 2;

A gate insulating film 3 for the gate electrode of T;

(Amorphous silicon film 4 forming a TFT channel region formed on the first insulating film (gate insulating film) 3 of the

(e) a video signal wiring 5 which also serves as a source electrode connected to the TFT amorphous silicon film 4 and supplies a video signal;

(f) a passivation insulating film acting as a protective film of TFT, a second insulating film 6 forming a second insulator layer,

(g) a plurality of pixel electrodes 7 arranged in a matrix,

(h) a contact hole pattern 8 formed after removing the opening of the passivation insulating film which is the second insulating film 6,

(i) a contact hole pattern 10 after removing the opening of the first insulating film 3 layer;

(j) Drain electrode 1 1

It is composed of

In the above configuration,

(a) The plurality of pixel electrodes 7 are arranged in a matrix.

(b) A plurality of TFTs are also arranged in a matrix in correspondence with the pixel electrodes 7.

(c) The video signal wiring 5 doubles as a source electrode connected to the TFT amorphous silicon film 4 and supplies a video signal to the pixel electrode 7 via the drain electrode 11.

(d) The second insulating film 6 is a passivation insulating film acting as a protective film of the TFT, and forms a second insulating layer. The operation of the AMT LCD device configured as described above will be described below.

Conventional AMT LCD device

(a) First, a voltage is applied to the scanning signal wiring 2,

(b) The voltage forms a TFT channel in the amorphous silicon film 4,

(c) When the channel is formed, the video signal from the video signal wiring 5 flows into the drain electrode 11 through the TFT channel,

(d) Further, the video signal is transmitted to the pixel electrode 7,

(e) An electric field is injected between the pixel electrode 7 and the counter electrode by an electric field between the pixel electrode 7 and a counter electrode (not shown) provided in a color filter (not shown) facing the pixel electrode 7 in parallel. (F) arbitrarily changing the orientation of the interposed liquid crystal, and (f) arbitrarily changing the orientation of the liquid crystal to adjust the light transmittance.

By this operation, a desired image is created and the image is displayed on the screen of the AMT LCD device. In such an AMT LCD apparatus, an array process step for forming a TFT on the glass substrate 1 is as follows.

(a) After forming a thin film,

(b) forming a resist pattern by a photolithography process;

(c) After removing unnecessary thin film portions by etching,

(d) Remove the resist pattern

This is a long and complicated process that is repeated in a cycle.

Reducing the number of cycles in this lithography process and shortening the lead time for all manufacturing processes This leads to lower product costs and lower reject rates. The lithography process in the manufacturing process of the AMTLCD device as described above

(a) forming a pattern for forming the scanning signal wiring 2;

(b) forming a pattern for forming the video signal wiring 5 and the drain electrode 11;

(c) forming a pattern for forming the amorphous silicon film 4,

(d) forming a pattern for forming the pixel electrode 7;

(e) forming a pattern for removing the opening of the passivation insulating film 6 for mounting and wiring the scanning signal wiring 2 and the video signal wiring 5;

(f) Further, a pattern for removing an opening in the first insulating film (gate insulating film) 3 to convert a layer of the scanning signal wiring 2 and a layer of the video signal wiring 5 is formed.

Will be repeated six times in total. However, in the conventional manufacturing method for manufacturing an AMTLC device as described above, the number of photolithography process cycles is six as described above. The lithographic process has a problem in that the overall process lead time becomes very long, which causes a rise in cost in the entire manufacturing process. Guidance of invention

The present invention solves the above-mentioned conventional problems, and can reduce the number of photolithography process cycles in a TFT array process, shorten the overall process lead time including that process, and provide a TFT array. Provided is an AMTLCD device and a method for manufacturing the same, which can reduce costs in the entire manufacturing process. In order to solve the above problems, an AMTLCD device and a method of manufacturing the same according to the present invention include (a) forming a pattern for removing an opening in a second insulating layer for mounting and wiring a scanning signal wiring and a video signal wiring;

(b) Pattern formation for removing the opening of the first insulating layer in order to convert between the scanning signal wiring layer and the video signal wiring layer

Are performed simultaneously (同時に times).

Therefore, the number of cycles of the photolithography step in the TFT array process is five. Further, the invention is characterized in that the scanning signal wiring layer and the video signal wiring layer are electrically connected using the pixel electrode layer.

The AMTLCD device of the present invention

(a) sandwiching liquid crystal between opposing insulating transparent substrates,

(b) The liquid crystal is driven by a scanning signal and a video signal corresponding to a display image to display an image on the screen.

In the AMTLCD device, the configuration of an array portion in which a plurality of pixels for image display are arranged in a matrix on the insulating transparent substrate is as follows:

(a) at least a plurality of pixel electrodes arranged in a matrix corresponding to each pixel;

(b) a plurality of switching elements composed of thin film transistors arranged corresponding to each of the pixel electrodes,

(c) a plurality of scanning signal lines for supplying the scanning signal to each gate electrode of the plurality of switching elements;

(d) a plurality of video signal wirings for supplying the video signal to the pixel electrode via each source electrode and drain electrode of the plurality of switching elements; (e) a first insulating layer laminated on the plurality of scanning signal wirings and serving as an insulating film for the gate electrodes of the plurality of switching elements;

(f) a second insulating layer laminated on the plurality of video signal wirings and serving as a protective film for the plurality of switching elements;

It has.

With the above configuration, the active matrix liquid crystal display device of the present invention is

(a) a part of the pixel electrode is electrically connected to the video signal wiring via a contact tree pattern formed on the video signal wiring and the second insulating layer; Formed so as to be electrically conductive via contact hole patterns formed in the first and second insulating layers, and (c) the switching element based on the scanning signal and the video signal. The liquid crystal is driven through the pixel electrode to display an image. As described above, the number of photolithography process cycles in the TFT array process can be reduced, the overall process lead time including that process can be shortened, and costs in the entire TFT array manufacturing process can be reduced. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional configuration diagram illustrating an AMTLC device and a method of manufacturing the same according to an embodiment of the present invention.

FIG. 2 is a cross-sectional configuration diagram showing a conventional AMTLC device and a method of manufacturing the same.

Embodiment 1 Hereinafter, an AMT LCD device and a method of manufacturing the same according to an embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a partial cross-sectional view of an AMT LCD device according to the present embodiment, and the same portions as those in FIG.

As shown in FIG. 1, the AMT LCD device of the present embodiment

(a) a glass substrate 1 which is an insulating transparent substrate,

(b) a scanning signal wiring 2 which also serves as a TFT gate electrode arranged in a matrix on a glass substrate 1 and supplies a scanning signal to the TFT gate electrode;

(c) a first insulating film forming a first insulating layer laminated on the scanning signal wiring 2;

A gate insulating film 3 for the gate electrode of T;

(d) an amorphous silicon film 4 forming a TFT channel region formed on a first insulating film (gate insulating film) 3 of the TFT;

(f) a second insulating film 6 serving as a passivation insulating film acting as a TFT protective film, forming a second insulating layer;

(g) a plurality of pixel electrodes 7 arranged in a matrix,

(h) a contact hole pattern 8 formed after removing the opening of the passivation insulating film as the second insulating film 6,

(i) a contact hole pattern 9 between the pixel electrode 7 and the scanning signal wiring 2; and (j) a drain electrode 11 connected to the amorphous silicon film 4 of TFT.

In the above configuration,

(a) A plurality of pixel electrodes 7 are arranged in a matrix. (b) A plurality of TFTs are also arranged in a matrix corresponding to the pixel electrodes 7.

(d) The second insulating film 6 is, for example, SiNx, Si02, acrylic resin, polyimide, polyamide, polycarbonate, or a laminated film of these.

(e) The pixel electrode 7 and the drain electrode 11 are electrically connected via the contact hole pattern 8. The difference between FIG. 1 showing the present embodiment and FIG. 2 showing the conventional example is as follows.

The difference is that the layer of the scanning signal wiring 2 and the layer of the video signal wiring 5 are electrically connected. Conventionally, as shown in FIG. 2, the contact hole pattern 10 is provided after the opening of the layer of the first insulating film 3 is removed. Then, the scanning signal wiring 2 and the video signal wiring 5 were directly electrically connected.

On the other hand, in the present embodiment, as shown in the wiring conversion section in FIG. 1, the opening on the surface of the scanning signal wiring 2 is formed by the first insulating film 3 and the second insulating This is performed by removing the film 6 at the same time. The contact hole pattern 9 is formed between the pixel electrode 7 and the scanning signal wiring 2 so that a part of the pixel electrode 7 is electrically connected to the scanning signal wiring 2 in the surface opening. With this formation, the scanning signal wiring 2 and the video signal wiring 5 are electrically connected indirectly via the pixel electrode 7.

In the present embodiment,

(a) formation of a pattern for removing an opening in a passivation insulating film which is a second insulating film 6 for mounting the scanning signal wiring 2 and the video signal wiring 5, (b) The pattern for opening and removing the gate insulating film, which is the first insulating film 3, for converting the layer of the scanning signal wiring 2 and the layer of the video signal wiring 5 is performed simultaneously (one time).

Therefore, the number of cycles of the photolithography process can be set to five. The lead time in the whole manufacturing process can be shortened, and the cost in the whole process is reduced.

As a method of making an array substrate of an AMLTC device having such a configuration,

(a) First, a scanning signal wiring 2 is thin-film deposited on a glass substrate 1 by a sputtering film forming method,

(b) Patterning of the scanning signal wiring 2 is performed in a lithography process and an etching process.

By repeating such patterning of thin film deposition, photolithography step and etching step, the step of the present invention is:

(a) An amorphous silicon film 4 is formed,

(b) forming the video signal wiring 5,

(c) and forming a drain electrode〗 1,

(d) The pixel electrode 7 is formed.

As described above, the surface opening of the scanning signal wiring 2 in the wiring conversion unit is formed by simultaneously removing the first insulating film 3 and the second insulating film 6 after the deposition of the second insulating film 6. The scanning signal wiring 2 and the video signal wiring 5 are configured to be electrically connected indirectly via the pixel electrode 7. In the AMTLC device thus configured, the scanning signal wiring 2 and the video signal wiring 5 are mounted and mounted.

(a) forming a pattern for removing an opening in the passivation insulating film;

(b) Forming a pattern for removing an opening in the gate insulating film in order to convert between the layer of the scanning signal wiring 2 and the layer of the video signal wiring 5 Are done simultaneously (once).

Therefore, the photolitho cycle can be set to 5 times.

As a result, it is possible to significantly reduce the number of steps required for the array process, such as thin film deposition, photolithography, etching, and other cleaning steps. In addition, the array process lead time can be significantly reduced, and the process cost can be reduced. Industrial applicability

As described above, according to the present invention, a pattern for removing an opening in the second insulating layer for mounting and wiring the scanning signal wiring and the video signal wiring is formed, and the scanning signal wiring layer and the video signal wiring are formed. At the same time, a pattern for removing the opening of the first insulating layer is formed (one time) in order to convert the layers of the TFT and the layers of the TFT array. The scanning signal wiring layer and the video signal wiring layer can be electrically connected using the electrode layer.

Therefore, the number of cycles of the photolithography process in the TFT array process can be reduced, the entire process lead time including that process can be shortened, and the cost in the entire TFT array manufacturing process can be reduced.

Claims

The scope of the claims

1. An active matrix liquid crystal display device,

(a) a plurality of scanning signal wirings for supplying a scanning signal to each gate electrode of a plurality of switching elements;

(b) a plurality of video signal wirings for supplying a video signal to a pixel electrode via each source electrode and drain electrode of the plurality of switching elements;

(c) a first insulating layer for the gate electrodes of the plurality of switching elements stacked on the plurality of scanning signal wirings,

(d) a second insulating layer laminated on the plurality of video signal wirings and corresponding to the plurality of switching elements;

With

(e) a part of the pixel electrode is electrically connected to the video signal wiring via a contact hole pattern formed in the second insulating layer, and the scanning signal wiring is connected to the first and second insulating layers. Conduction through the contact hole pattern formed in the

It is characterized in that it is formed as follows.

2. The active matrix liquid crystal display device according to claim 1, wherein the first insulating layer has a laminated structure including a semiconductor layer.

3. The active matrix liquid crystal display device according to claim 1 or 2, wherein the second insulating layer is a transparent resin such as an acrylic resin, a polyimide, a polyamide, or a polycarbonate. It is characterized by having a laminated structure including.

4. A method of manufacturing an active matrix liquid crystal display device, wherein a plurality of pixels for displaying an image includes a plurality of switching elements in an array portion arranged in a matrix on an insulating transparent substrate. As the element formation process,

(a) A first method in which at least a plurality of scanning signal wirings for supplying a scanning signal to each gate electrode of the plurality of switching elements and a gate dummy wiring serving as each of the gate electrodes are formed by selective etching. (B) a second step of defining each channel of the plurality of switching elements;

(c) selecting and etching a plurality of video signal lines for supplying the video signals to the pixel electrodes via the respective source electrodes and drain electrodes of the plurality of switching elements, and a source dummy line serving as the respective source electrodes; A third step of forming

(d) an insulating film laminated on the plurality of scanning signal wirings to form a gate electrode of the plurality of switching elements and a protective film laminated to the plurality of video signal wirings on the plurality of switching elements; A fourth step of selectively etching the insulating layer and simultaneously opening the plurality of scanning signal wirings and the plurality of video signal wirings on the surface;

(e) a fifth step of forming the pixel electrode by selective etching, and (f) forming a mounting terminal on one of the layers of the scanning signal wiring or the video signal wiring, and forming a mounting terminal thereon. A sixth step of laminating the layers and pressure-bonding the layers using a conductive film such as an anisotropic conductive film.

5. Paper corrected by the method of manufacturing an active matrix liquid crystal display device according to claim 4 (Rule 91) The first to sixth steps are performed in that order.