JP2000081638A - Liquid crystal display device and manufacturing method thereof - Google Patents

Abstract

(57) Abstract: A liquid crystal display device and a method of manufacturing the same capable of reducing the number of cycles in a photolithography process, shortening the process lead time, and reducing the cost in the entire manufacturing process of a TFT array. provide. SOLUTION: A pattern for removing an opening in a second insulating film 6 for mounting and wiring the scanning signal supply wiring 2 and the video signal supply wiring 5, a layer of the scanning signal supply wiring 2 and a layer of the video signal supply wiring 5 are provided. And a pattern for removing the opening of the first insulating film 3 is simultaneously formed once in order to convert the layers into layers.
The number of photolithography steps in the FT array process is set to five, and the layer of the scanning signal supply wiring 2 and the layer of the video signal supply wiring 5 are electrically connected using the layer of the pixel electrode 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix type liquid crystal display device for displaying an image by driving a liquid crystal by a switching element, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, display devices using liquid crystal for displaying images have been widely used because they are thin, light and have low power, which are not available in displays using conventional CRTs. In particular, a thin film transistor (hereinafter, referred to as a thin film transistor) is provided for each pixel arranged in a matrix.
An active matrix type liquid crystal display device having a switching element composed of a TFT (which is abbreviated as TFT) and driving the liquid crystal by the switching element to display an image can provide a clear image display with little crosstalk, so that it can be used in a notebook computer or a car. It is used for a display of a navigation device and the like, and has recently been rapidly used.

Hereinafter, an example of a conventional active matrix type liquid crystal display device will be described with reference to the drawings.
FIG. 2 is a sectional view of an array portion having a TFT of a conventional active matrix type liquid crystal display device. In FIG. 2, reference numeral 2 denotes TFs arranged in a matrix on a glass substrate 1 which is an insulating transparent substrate in a TFT array portion.
A scanning signal supply line 3 which also serves as a gate electrode of T and supplies a scanning signal to the gate electrode of the TFT, 3 is a first insulating film forming a first insulator layer laminated on the scanning signal supply line 2, and Gate insulating film for the gate electrode of
An amorphous silicon semiconductor film for forming a TFT channel region formed on a first insulating film (gate insulating film) 3 of FT, and a plurality of pixel electrodes 7 are arranged in a matrix. In response to this, a plurality of TFTs are arranged in a matrix. Reference numeral 5 denotes a video signal supply line which also serves as a source electrode connected to the amorphous silicon semiconductor film 4 of the TFT and supplies a video signal to the pixel electrode 7 via the drain electrode 11. Reference numeral 6 denotes a passivation insulating film that functions as a protective film of the TFT, and is a second insulating film that forms a second insulator layer.

[0004] The operation of the liquid crystal display device configured as described above will be described below. First, when a voltage is applied to the scanning signal supply wiring 2 and a TFT channel is formed in the amorphous silicon semiconductor film 4, a video signal from the video signal supply wiring 5 passes through the TFT channel to the drain electrode 11. The counter electrode (not shown) provided in a color filter (not shown) portion which flows into the pixel electrode 7 and is opposed to the pixel electrode 7 in parallel.
A desired image is created by arbitrarily changing the orientation of the liquid crystal injected and sandwiched between the pixel electrode 7 and the counter electrode and adjusting the light transmittance by the electric field between the pixel electrode 7 and the counter electrode. Display an image on the screen.

In such a liquid crystal display device, generally, in an array process step for forming a TFT on the glass substrate 1, after forming a thin film, a resist pattern is formed by a photolithography step, and an unnecessary thin film portion is removed by etching. This is a long and complicated process in which the operation of removing the resist pattern after the process is repeated in a cyclic manner. Reducing the number of cycles in the photolithography process to shorten the lead time in all the manufacturing processes leads to a reduction in cost and defective rate for products.

In the manufacturing process of the liquid crystal display device as described above, generally, as a photolithography process, a scanning signal supply wiring 2, a video signal supply wiring 5, a drain electrode 11, and an amorphous silicon semiconductor film 4 are formed. Pattern formation, pattern formation for forming the pixel electrode 7, pattern formation for removing the opening of the passivation insulating film 6 for mounting and wiring the scanning signal supply wiring 2 and the video signal supply wiring 5, and further, the scanning signal supply wiring 2 The pattern formation for removing the opening of the first insulating film (gate insulating film) 3 in order to convert the layer of the first signal and the layer of the video signal supply wiring 5 is repeated a total of six times.

[0007]

However, in the above-described conventional method for manufacturing a liquid crystal display device, as described above, the number of photolithography process cycles is six, and the number of photolithography processes is six. Has a problem in that the process lead time becomes very long, which causes a rise in cost in the entire manufacturing process.

The present invention solves the above-mentioned conventional problems. The present invention can reduce the number of photolithography process cycles in the TFT array process, shorten the overall process lead time including that process, and improve the TFT array process. Provided are a liquid crystal display device and a method for manufacturing the liquid crystal display device, which can reduce costs in all manufacturing processes.

[0009]

In order to solve the above-mentioned problems, a liquid crystal display device and a method of manufacturing the same according to the present invention include a second insulator layer for mounting and wiring scanning signal supply wiring and video signal supply wiring. Pattern formation for removing openings,
In order to convert the layer of the scanning signal supply wiring and the layer of the video signal supply wiring, the pattern formation for removing the opening of the first insulator layer is simultaneously performed once, and the number of photolithography process cycles in the TFT array process is performed. Is repeated five times, and the scanning signal supply wiring layer and the video signal supply wiring layer are electrically connected using the pixel electrode layer.

As described above, the number of cycles of the photolithography process in the TFT array process can be reduced, and the overall process lead time including that process can be shortened.
The cost in the whole manufacturing process of the TFT array can be reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display device according to a first aspect of the present invention is a display device for displaying an image on a screen using liquid crystal, wherein the liquid crystal is sandwiched between opposing insulating transparent substrates. In a liquid crystal display device that drives the liquid crystal by a scanning signal and a video signal corresponding to a display image to display an image on the screen, a plurality of pixels for displaying the image are arranged in a matrix on the insulating transparent substrate. As constituent elements of the array portion arranged in at least, at least a plurality of pixel electrodes arranged in a matrix corresponding to the pixels, and a plurality of switching elements formed of thin film transistors arranged corresponding to the pixel electrodes A plurality of scanning signal supply lines for supplying the scanning signal to each gate electrode of the plurality of switching elements; and a plurality of source electrodes of the plurality of switching elements and A plurality of video signal supply wirings for supplying the video signal to the pixel electrode via a rain electrode, and a first film which is stacked on the plurality of scanning signal supply wirings and serves as an insulating film for a gate electrode of the plurality of switching elements. A second insulating layer, which is laminated on the plurality of video signal supply wirings and serves as a protective film for the plurality of switching elements.
A part of the pixel electrode is electrically connected to a video signal supply line via a contact hole pattern formed in the second insulator layer, and a scan signal supply line is provided. Is formed so as to be electrically conductive through contact hole patterns formed in the first and second insulator layers, and the liquid crystal is passed through the pixel electrode by turning on and off the switching element by the scanning signal and the video signal. It is configured to drive and display an image.

A liquid crystal display device according to a second aspect is configured such that the first insulator layer according to the first aspect has a laminated structure including a semiconductor layer. According to a third aspect of the present invention, in the liquid crystal display device, the second insulating layer according to the first or second aspect is a transparent resin such as an acrylic resin, a polyimide, a polyamide, or a polycarbonate, or has a laminated structure including these. And

According to a fourth aspect of the present invention, there is provided a display device for displaying an image on a screen using a liquid crystal, wherein the liquid crystal is sandwiched between opposed insulating transparent substrates, and the liquid crystal is formed. In a method of manufacturing a liquid crystal display device that turns on and off a plurality of switching elements according to a scanning signal and a video signal corresponding to a display image and drives the pixel through a pixel electrode to display an image on the screen, a plurality of pixels for displaying the image are displayed. As a process of forming a component including the plurality of switching elements in an array portion arranged in a matrix on the insulating transparent substrate, at least a plurality of scans for supplying a scanning signal to each gate electrode of the plurality of switching elements A first step of selectively etching and forming a signal supply wiring and a gate dummy wiring serving as each of the gate electrodes; A second step of defining each channel portion of the switching element; a plurality of video signal supply wirings for supplying the video signal to the pixel electrode via each source electrode and drain electrode of the plurality of switching elements; and A third step of selectively etching and forming a source dummy wiring serving as a source electrode; an insulating film laminated on the plurality of scanning signal supply wirings to a gate electrode of the plurality of switching elements; and the plurality of video signals. A fourth step of selectively etching each of the insulator layers which are stacked on the supply wiring and serve as protection films for the plurality of switching elements, and simultaneously opening the plurality of scanning signal supply wirings and the plurality of video signal supply wirings on the surface; A fifth step of forming the pixel electrode by selective etching, and any one of the scanning signal supply wiring and the video signal supply wiring. Forming a mounting terminal on one of the layers, by laminating a layer of the pixel electrode thereon, crimp implemented using a conductive film of the anisotropic conductive film or the like thereon sixth
And a method of executing the first to sixth steps in that order.

According to the above configuration and method, a pattern is formed for removing an opening in the second insulator layer for mounting and wiring the scanning signal supply wiring and the video signal supply wiring. A pattern for opening and removing the first insulator layer is simultaneously formed once in order to convert a layer of the supply wiring to a layer, and the number of photolithography steps in the TFT array process is reduced to five, and the pixel electrode is formed. The electrical connection is made between the scanning signal supply wiring layer and the video signal supply wiring layer by using the above layers.

Hereinafter, a liquid crystal display device and a method for manufacturing the same according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partial cross-sectional view of an active matrix type liquid crystal display device of the present embodiment, and the same portions as those of FIG. 2 showing a conventional example are denoted by the same reference numerals. 1 and 2, reference numeral 1 denotes a glass substrate which is an insulating transparent substrate, and 2 denotes a gate electrode of the TFTs arranged in a matrix on the glass substrate 1 in the TFT array portion. A scanning signal supply wiring 3 for supplying a signal is a first insulating film forming a first insulator layer laminated on the scanning signal supply wiring 2, and a TFT
The gate insulating film for the gate electrode of the TFT, 4 is the first of the TFT
An amorphous silicon semiconductor film forming a channel region of a TFT formed on the insulating film (gate insulating film) 3;
Reference numeral 5 denotes a video signal supply line which also serves as a source electrode connected to the amorphous silicon semiconductor film 4 of the TFT and supplies a video signal to the pixel electrode 7 via the drain electrode 11, and 11 is connected to the amorphous silicon semiconductor film 4 of the TFT The drain electrode 7 is a pixel electrode in which a plurality of pixels are arranged in a matrix in order to form a pixel on the screen, and the TFTs are also arranged in a matrix corresponding to the pixel electrode 7. Reference numeral 6 denotes a protective film which is a second insulating film forming a second insulator layer, and is, for example, SiNx, SiO ₂ , acrylic resin, polyimide, polyamide, polycarbonate, or a laminated film thereof, and is a passivation insulating film of a TFT. is there. Reference numeral 8 denotes a contact hole pattern formed after the opening of the passivation insulating film serving as the second insulating film 6 is removed. The pixel electrode 7 and the drain electrode 11 are electrically connected through the contact hole pattern 8.

The structure described so far is a conventional example shown in FIG.
The difference between FIG. 1 showing the present embodiment and FIG. 2 showing the conventional example is as follows. That is, when the above-described layer of the scanning signal supply wiring 2 and the layer of the video signal supply wiring 5 are electrically connected to perform layer conversion between the respective layers, conventionally, as shown in FIG. After the opening of the layer of the film 3 was removed, a contact hole pattern 10 was provided, and the scanning signal supply wiring 2 and the video signal supply wiring 5 were directly electrically connected.

On the other hand, in the present embodiment, as shown in the wiring conversion section of FIG. 1, an opening in the surface of the scanning signal supply wiring 2 is formed with the first insulating film 3 after the deposition of the second insulating film 6. The contact is performed between the pixel electrode 7 and the scanning signal supply line 2 so that a part of the pixel electrode 7 is electrically connected to the scanning signal supply line 2 at the surface opening of the second insulation film 6. By forming the hole pattern 9, the scanning signal supply wiring 2 and the video signal supply wiring 5 are configured to be electrically connected indirectly via the pixel electrode 7.

Forming a pattern for removing an opening in a passivation insulating film which is a second insulating film 6 for mounting the scanning signal supply wiring 2 and the video signal supply wiring 5, a layer of the scanning signal supply wiring 2 and the video signal supply wiring 5 The pattern for opening and removing the gate insulating film, which is the first insulating film 3 for converting the layers of the layers, is simultaneously formed once, and the number of cycles of the photolithography process is set to five, and the lead time in the entire manufacturing process is increased. Can be reduced, and costs in the entire process can be reduced.

As a method of forming an array substrate of a liquid crystal display device having such a configuration, first, a scanning signal supply wiring 2 is thin-film deposited on a glass substrate 1 by a sputtering film forming method, and a photolithography process and an etching process are performed. The scanning signal supply wiring 2 is patterned. By repeating the patterning of the thin film deposition, the photolithography step, and the etching step, the amorphous silicon semiconductor film 4, the video signal supply wiring 5, the drain electrode 11, and the pixel electrode 7 are formed.

As described above, the removal of the surface opening of the scanning signal supply wiring 2 in the wiring conversion unit is performed on the first insulation film 3 and the second insulation film 6 simultaneously after the deposition of the second insulation film 6 to supply the scanning signal. In a liquid crystal display device in which the wiring 2 and the video signal supply wiring 5 are electrically connected indirectly via the pixel electrode 7, the wiring 2 and the video signal supply wiring 5 are mounted and wired. Simultaneously forming a pattern for removing the opening of the passivation insulating film, and simultaneously forming a pattern for removing the opening of the gate insulating film to convert the layer of the scanning signal supply wiring 2 and the layer of the video signal supply wiring 5 into layers. 1
The photolithography cycle can be performed five times.

As a result, in the array process, those requiring many steps such as thin film deposition, photolithography, etching, and other cleaning steps can be greatly reduced, and the array process lead time is also significantly reduced. And the process cost can be reduced.

[0022]

As described above, according to the present invention, a pattern for removing an opening in the second insulator layer for mounting and wiring the scanning signal supply wiring and the video signal supply wiring, and the formation of the scanning signal supply wiring. A pattern for opening and removing the first insulator layer is simultaneously formed once to convert the layer and the layer of the video signal supply wiring into one layer, and the number of photolithography steps in the TFT array process is set to five. In addition, the scanning signal supply wiring layer and the video signal supply wiring layer can be electrically connected using the pixel electrode layer.

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

[Brief description of the drawings]

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

FIG. 2 is a sectional view showing a conventional liquid crystal display device and a method for manufacturing the same.

[Explanation of symbols]

Reference Signs List 1 glass substrate 2 scanning signal supply wiring (gate electrode) 3 first insulating film 4 amorphous silicon semiconductor film 5 video signal supply wiring (source electrode) 6 second insulating film 7 pixel electrode 8 (between pixel electrode and video signal supply wiring) Contact hole pattern 9 (between pixel electrode and scanning signal supply wiring) Contact hole pattern 10 (between video signal supply wiring and scanning signal supply wiring) Contact hole pattern 11 Drain electrode

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H092 JA26 JA29 JA38 JA42 JA44 JB13 JB23 JB32 JB33 JB56 KA07 KA12 KA16 KA18 KB14 KB23 KB24 MA05 MA08 MA14 MA15 MA16 MA18 MA19 MA20 NA13 NA15 NA25 NA27 NA29 PA06 QA07

Claims (4)

[Claims] 1. A display device for displaying an image on a screen using a liquid crystal, wherein the liquid crystal is sandwiched between opposing insulating transparent substrates, and the liquid crystal is driven by a scanning signal and a video signal corresponding to a display image. Then, in the liquid crystal display device for displaying an image on the screen, a plurality of pixels for displaying the image are arranged at least in each pixel as a component of an array portion arranged in a matrix on the insulating transparent substrate. A plurality of pixel electrodes arranged in a matrix corresponding to
A plurality of switching elements formed of thin film transistors arranged corresponding to the pixel electrodes, a plurality of scanning signal supply wirings for supplying the scanning signals to respective gate electrodes of the plurality of switching elements, and a plurality of switching elements. A plurality of video signal supply wirings for supplying the video signal to the pixel electrode via each source electrode and a drain electrode; and an insulating film laminated on the plurality of scanning signal supply wirings to a gate electrode of the plurality of switching elements A first insulator layer, and a second insulator layer laminated on the plurality of video signal supply wirings and serving as a protective film for the plurality of switching elements. Are electrically connected to the video signal supply wiring via a contact hole pattern formed in the second insulator layer, and are electrically connected to the scan signal supply wiring. And an electrically conductive pattern formed through a contact hole pattern formed in the second insulator layer, and the liquid crystal is driven through the pixel electrode by turning on and off the switching element by the scanning signal and the video signal, thereby forming an image. A liquid crystal display device for displaying. 2. The liquid crystal display device according to claim 1, wherein the first insulator layer has a stacked structure including a semiconductor layer. 3. The liquid crystal display according to claim 1, wherein the second insulator layer is a transparent resin such as an acrylic resin, a polyimide, a polyamide, or a polycarbonate, or has a laminated structure including these. apparatus. 4. A display device for displaying an image on a screen using liquid crystal, wherein said liquid crystal is sandwiched between opposing insulating transparent substrates, and said liquid crystal is formed by a plurality of scanning signals and video signals corresponding to a display image. In the method for manufacturing a liquid crystal display device that turns on and off the switching element and drives the pixel electrode through a pixel electrode to display an image on the screen, a plurality of pixels for displaying the image are arranged in a matrix on the insulating transparent substrate. As a process of forming a component including the plurality of switching elements in the array portion, at least a plurality of scanning signal supply lines for supplying a scanning signal to each gate electrode of the plurality of switching elements and a gate dummy serving as each of the gate electrodes A first step of forming a wiring by selective etching, and a second step of defining each channel of the plurality of switching elements. And a plurality of video signal supply lines for supplying the video signal to the pixel electrode via each source electrode and drain electrode of the plurality of switching elements,
A third step of selectively etching a source dummy wiring to be each of the source electrodes, forming an insulating film on the plurality of scanning signal supply wirings for a gate electrode of the plurality of switching elements, and Selectively etching each of the insulator layers that are stacked on the video signal supply wirings and serve as protective films for the plurality of switching elements, and simultaneously opening the plurality of scanning signal supply wirings and the plurality of video signal supply wirings on the surface. Step 4, a fifth step of forming the pixel electrode by selective etching, and forming a mounting terminal in one of the scanning signal supply wiring and the video signal supply wiring, and further forming the pixel electrode on the mounting terminal. A sixth step of laminating the above-mentioned layers and press-fitting thereon using a conductive film such as an anisotropic conductive film, and performing the first to sixth steps in that order. Method of manufacturing a liquid crystal display device according to claim Rukoto.