JPH036532A - Manufacture of display electrode substrate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a display electrode substrate used in an active matrix color display device.

Conventional technology A thin film transistor (Tb1
A display ZM formed by arranging n Film Transistors (hereinafter abbreviated as TPT) in a matrix.
Advantages of active matrix type liquid crystal display devices using substrates include the fast response speed of liquid crystals, and there is no restriction on the area of the insulating substrate used as the display electrode substrate, making it applicable to both reflective and transmissive types. Because of this, it is considered promising as a large-capacity display device.

FIG. 4 is a cross-sectional view schematically showing the conventional structure of such an active matrix color liquid crystal display device. In FIG. 4, a plurality of transparent picture element electrodes 2 corresponding to each picture element and a plurality of TFTs 3 connected to each transparent picture element electrode 2 in a one-to-one correspondence are arranged in a matrix on a transparent insulating substrate 1. The alignment film 4 is formed on the entire surface.
are formed to constitute the display electrode substrate 5.

On the other hand, on the surface side facing the other transparent insulating substrate 1 of another transparent insulating substrate 6 disposed opposite to the transparent insulating substrate 1, color filters 7 are provided at positions facing each transparent picture element electrode 2. is formed, a transparent counter electrode 8 is formed on the entire surface thereof, and an orientation M9 is further formed on the entire surface thereof, thereby forming a counter substrate 10. A liquid crystal layer 11 is interposed between these two substrates 5.degree. 10, and the liquid crystal layer 11 is sealed by a sealing member 12.

Further, a polarizing plate 13 is disposed on the surface of the display electrode substrate 5 opposite to the surface on which the alignment film 4 is formed, and a polarizing plate 14 is also disposed on the surface of the counter substrate 10 on the opposite side to the surface on which the alignment film 9 is formed. It is located.

Furthermore, a backlight light source 15 is separately arranged on the side of the front electrode substrate 5 where the polarizing plate 13 is arranged.

In the above color liquid crystal display device, when a voltage is selectively applied to each transparent picture element electrode 2 via the TFT 3, the transparent picture element electrode 8i! Each part of the liquid crystal layer 11 sandwiched between the liquid crystal layer 2 and the transparent counter electrode 8 is selectively driven on and off to change its optical characteristics. The backlight emitted from the backlight light source 15 passes through each part of the liquid crystal layer 11 that has changed to a light-transmissible state, and a color display is performed according to the color tone of the color filter corresponding to each part of the liquid crystal layer 11. ing.

In the case of the above color liquid crystal display device, if a part of the backlight that has passed through the liquid crystal layer 11 passes through the gap between adjacent color filters 7 on the counter substrate 10111, the color filter corresponding to the pixel portion Not only 7 but also
The surrounding areas also emit light, reducing the contrast ratio. Therefore, in order to avoid such an official, on the opposite substrate 10 side, each color filter 7 (R, G, B indicates the color of each color filter ) A light-shielding WX16 made of a metal film such as Cr is formed in the gap between the two, thereby preventing the backlight from passing through the gap.

Problems to be Solved by the Invention However, if the light shielding film 16 is formed in the gap between the color filters 7 on the opposite substrate 10 side as in the above-mentioned color liquid crystal display device, the problem arises as described below. The problem is that the element area decreases and the light transmittance, that is, the brightness decreases.

That is, when the display electrode substrate 5 on which the transparent picture element electrodes 2 and TFTs 3 are formed and the counter substrate 10 on which the color filters 7 are formed are placed facing each other and bonded together, the alignment accuracy of both substrates 5 and 10 is usually The line width of the light shielding film 16 (width of the portion covering between adjacent color filters 7) is approximately 10 μm, and therefore the line width of the light shielding film 16 (width of the portion covering between adjacent color filters 7) is smaller than the gap between the adjacent transparent picture element electrodes 2 on the display electrode substrate 5 side by the above alignment accuracy. It is necessary to form it as widely as possible. As a result, the picture element area decreases accordingly, and the light transmittance decreases.

Therefore, an object of the present invention is to provide a method of manufacturing a display electrode substrate in which each picture element has high light transmittance and can obtain good display contrast.

Means for Solving the Problems The present invention provides an active matrix multi-color display device in which picture element electrodes and color filters corresponding to each picture element, and switching elements connected to each picture element electrode are arranged in a matrix on an insulating substrate. In the method for manufacturing a display electrode substrate arranged in a row, a switching element and a picture element electrode are formed on an insulating substrate, and then a color filter is deposited and formed on the picture element electrode using an electrodeposition method, and the color filter is further arranged on the picture element electrode. A method for manufacturing a display electrode substrate, characterized in that a conductive film is deposited and formed on the entire remaining area of the insulating substrate, avoiding the formation area, and a light-shielding film is formed on the conductive film using an electrodeposition method. It is.

Function According to the present invention, after a switching element and a picture element electrode are formed on an insulating substrate, a color filter is deposited and formed on the picture element electrode by an electrodeposition method. Guide to all areas avoiding the color filter forming area
A is formed, and a light shielding film is deposited and formed on this conductive film by electrodeposition. Since the color filter is formed on the pixel electrode as the electrode for electrodeposition, the accuracy of the positioning of the pixel electrode (to) and the color filter and the positioning of the pixel electrode and the light-shielding film is improved, and the color filter is formed on the pixel electrode. The proportion of the light-shielding film that protrudes into the filter area, that is, the margin for positioning the color filter and the light-shielding film, can be reduced accordingly, and the light transmittance can therefore be increased. Furthermore, since light transmission around the color filter is sufficiently blocked, display contrast is also improved.

Embodiment 10 is a partially enlarged cross-sectional view of an active matrix color liquid crystal display device obtained by applying a method of manufacturing a display electrode substrate according to an embodiment of the present invention.

In FIG. 1, on the glass substrate 18 constituting the display electrode substrate 17, there are first a plurality of TFTs 19 and the TFTs.
A plurality of picture element electrodes Ff 120 made of ITO (indigo oxide) M are connected in a one-to-one correspondence to 19 and are arranged in a matrix. That is, a TPT gate electrode 21 (including a gate pass line serving as a scanning line) is first formed on the glass substrate 18, and then a gate insulating film 22 is formed thereon. Also game...
A semiconductor layer such as non-doped a-Si23 or phosphorus-doped a-3i24 is formed on the insulating film 22, and further thereon, a source electrode 25 (including a source pass line which becomes a data line) and a drain electrode M26 are formed; The TFT 19 is formed selectively. Then, the picture element electrode &20 is formed by overlapping a part of it on the drain '11HI26.

Next, the display electrode substrate 17, which is a semi-finished product in which the through-hole portion (not shown) of the drain plate 26 is covered with 7 OtoRegis 1-, is placed in the electrodeposition liquid 28 filled in the second (21) electrodeposition tank 27. In other words, a counter electrode 30 is separately immersed in the Th electrodeposition solution 28, and this counter electrode 30 and the source electrode 25 of the TFT 19 of the above-mentioned 'xi substrate 17 are immersed. By connecting the DC power supply 31 between T and T, a positive voltage (eg, 30 V) is applied to the source electrode 25,
By connecting another DC power supply 32 to the gate insulating film 21 of the FT 19, a positive voltage (for example, 20 cm) for turning on the TPT 19 is applied to the gate electrode 21.

At this time, the positive voltage applied to the source; pole 25 is applied to the TFT.
19 to the picture element i-pole 20, the polymer resin and pigment in the electrodeposition liquid 28 are attracted to the picture element electrode 20, and a color filter 2 made of a colored polymer resin film is formed on the picture element electrode 20.
is precipitated and formed. This electrodeposition process is performed separately using the electrodeposition liquids 28 of each color: red, green, and blue.

The entire surface of the display electrode substrate 17 on which the color filter 29 is formed in this way is coated with insulating transparent resin or
, and then a transparent electrode 34 made of, for example, an ITO film is formed on the entire surface of the insulating film 33.
is formed. Further, a photoresist is coated on the transparent electrode 34, and the photoresist is exposed and developed using a mask with a pattern that covers the gaps between the color filters 29 (thereby, the color filters 29 of the photoresist are exposed and developed). Using this photoresist as a mask, the transparent electrode 34 is selectively etched away. That is, the transparent electrode 34 is removed leaving only the portion covering the gap between the color filters 29. Ru.

Thereafter, a black light-shielding film 35 is formed by using the transparent electrode 34 as an electrode for electrodeposition and performing substantially the same process as the formation of the color filter 29 described above. In this place 6, the second (21
As the electrodeposition liquid 28 shown in FIG. 1, an 'S electrodeposition liquid containing an anionic polymer resin mixed with a black pigment is used.

That is, the anionic polymer resin to be melted and mixed in the electrodeposition liquid 28 contains five carboxyl groups, and during the electrodeposition process, the carboxyl anion R-Coo dissociated in the aqueous solution - is attracted to the transparent electrode 34 according to the reaction formula shown below, and the above-mentioned black light-shielding film 35 is formed.

2H20-448” +021+4e-・-11) R・
COO-+)do-R-C0OH (precipitation)...
(2) The electrodeposition liquid 28 in this case contains an iα form having the following composition.

Water-soluble polyester resin 160wt% Water-soluble melamine resin (butyl cellosolve) 40wt% Isopropyl alcohol Furthermore, the black pigment was dispersed in ethyl glycol at the following weight ratio, and then mixed into the above-mentioned liquid and water solution at the following weight ratio. The electrodeposited liquid 28 is made into an electrodeposition liquid 28.

Liquid = 10 water
: 12
0 ethylene glycol = 20 Figure 0 is
FIG. 3 is an enlarged plan view showing a part of the semi-finished display electrode substrate 17 on which the light shielding film 35 is formed in this manner. The cross section of the same mouth as seen from the arrow i- corresponds to the first eye.

The display electrode substrate 17 thus obtained is further laminated with a protective film 36 and an alignment film 37 on its surface, and then assembled into a liquid crystal display panel 40 with a counter substrate 38 with a liquid crystal layer 39 therebetween.

The counter substrate 38 is configured by forming a counter electrode 12 made of an IOT film on the surface of a glass substrate 41, and further forming an alignment film 43 on the surface thereof. In the conventional color liquid crystal described above, a clearing plate is disposed on the surface of the display electrode substrate 17 opposite to the surface on which the alignment film 37 is formed, and on the surface opposite to the surface on which the alignment film 37 is formed. This is the same as in a display device, and a backlight source (not shown) is arranged on the display electrode substrate 17 side of the liquid crystal display panel 40.

This color liquid crystal display device also performs color display in the same manner as conventional devices.

That is, when a voltage is selectively applied to each picture element electrode 20 via the TFT 19, each part of the three liquid crystal layers sandwiched between the picture element electrode 20 and the counter electrode 42 is selectively turned on and off, and optically Characteristics change.

In each part of the liquid crystal layer 39 that has changed to a state where light can be transmitted,
Backlight emitted from a backlight light source passes through two color filters, and each part of the liquid crystal layer 39 is displayed in a color according to the color tone of the corresponding color filter 29.

Effects of the Invention As described above, according to the method for manufacturing a display electrode substrate of the present invention, after forming a switching element and a picture element T4 pole on an insulating substrate, a color filter is deposited on the picture element electrode by an electrodeposition method.・A conductive film was formed on the insulating substrate, avoiding the area where the color filter was formed, and a light-shielding film was deposited and formed on this conductive film by electrodeposition, so that the picture element The accuracy of positioning the electrodes and color filters and the positioning of pixel electrodes and light-shielding films is improved, and the position of the color filters and light-shielding films is improved accordingly! The accuracy of alignment is improved, and the margin of alignment between the color filter and the light-shielding film can be kept small, and the light transmittance of the picture element is therefore increased. Furthermore, by improving the positioning accuracy, light transmission around the color filter is sufficiently blocked, and display contrast is also improved.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of a part of a color liquid crystal display device to which a method for manufacturing a display electrode substrate according to an embodiment of the present invention is applied, and FIG. 3121 is an enlarged plan view showing a part of the display electrode substrate in the middle of the process; FIG. 4 is a sectional view showing the mechanical structure of a conventional color liquid crystal display; and FIG. The figure is a plan view showing a pattern of a light shielding film in the color liquid crystal display device.

Claims (1)

[Scope of Claims] A display electrode in which a pixel electrode and a color filter corresponding to each pixel of an active matrix color display device, and a switching element connected to each pixel electrode are arranged in a matrix on an insulating substrate. In a method for manufacturing a substrate, after forming a switching element and a picture element electrode on an insulating substrate, a color filter is deposited and formed on the picture element electrode using an electrodeposition method, and further, a region where the color filter is formed is avoided. A method for manufacturing a display electrode substrate, comprising: depositing and forming a conductive film on the entire remaining area of the insulating substrate, and forming a light-shielding film on the conductive film using an electrodeposition method.