JPH01283519A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent signal wiring and an auxiliary capacitor from being short- circuited by leaving a semiconductor film, metal, and metal oxide on an insulating film at the intersection of the signal wiring and auxiliary capacitor and compensating a defect in the insulating film, and widening a layer interval. CONSTITUTION:A layer for protecting the insulating film such as the semiconductor film, metal, and metal oxide film is provided at the intersection of an auxiliary capacity electrode 5 and a drain electrode 1. Then, if the insulating film has a projection, pinhole, or dust, an amorphous silicon film 2, ITO film 6, or Cr film 7 is left on a 2nd layer insulating film 4 or in the intermediate layer between a 1st layer insulating film 3 and the 2nd layer insulating film 4. The thin insulating film at the intersection of the auxiliary capacity electrode 5 and drain electrode 1 is not etched, the defect in the insulating film is compensated by the intervention of the conductive film 8, and the layer interval between two kinds of conductors increases. Consequently, a short circuit is prevented from being generated at the intersection of the auxiliary compensating electrode 5 and drain electrode 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an active matrix liquid crystal display device using a thin film transistor (TPT) or an MIM device as a switching element.

(Incorporated) Conventional technology active matrix type liquid crystal display device is Sanyo Electric Technical Report vo16. No. 2.1984 (2) As shown, C2 multiple gate lines, C2 orthogonal drain lines and their intersections (:TFTY were formed, and the display electrode and 'I'FT were connected. The substrate (two pairs of inner electrodes face each other, and the liquid crystal is sandwiched between them). In the conventional technology, each picture element 1: Auxiliary capacitance electrodes (5) such as those shown in Fig. 2) are attached to these auxiliary capacitances between the display electrode and the counter electrode. Since it compensates for the drop in applied voltage due to the leakage current C2 when the TPT, MIM) is off, this capacitor C2 improves the maintenance of the 1 voltage applied to the liquid crystal, and also reduces the consumption of the drive circuit that drives the liquid crystal display device. Power is being lowered.

On the other hand, as shown in Figure 2 (G)
On the substrate, the auxiliary capacitance electrode (5) and the drain electrode (11 are the -th
The layer insulating film (3) and the second layer insulating film (4) intersect with each other, and the metal and metal oxide are usually etched once they are formed in O'/D. be. On the other hand, in order to improve image quality, it is necessary to increase the number of pixels per area, reduce the wiring width, and reduce the level difference in wiring.

For this reason, an insulating film of several hundred amperes is sometimes used, and defects in the insulating film and dust on the surface of the Urasuke IT before film formation and on the film may cause the auxiliary capacitance electrode (5) and the drain voltage. (1
) is likely to occur. Conventionally, 1
For 00,000 intersection points, short circuits occurred in dozens of points.

By the way, is it possible to create a short circuit between the gate and drain by leaving the highly insulating amorphous silicon film (2) below the drain and source at the intersection of the gate and drain as shown in Figure 2 (CA)? There are already two inventions that prevent this. (Jitsugan 1986
-40617] (C) Problems to be Solved by the Invention Conventional technology C Then, when etching the amorphous silicon film (2) shown in Figure 1 (Fig. 1), the buried dust is removed and the - Membrane (3
) A hole is formed or the insulation becomes thin enough to impair its insulation properties, and on top of that, a short circuit occurs due to the formation of a pole (1) on the C hole.

Is this the point of this invention? The solution is to increase the interlayer spacing between the two types of conductors without specifying the intervening substance, which may lead to an increase in the gap between the layers.)
The overall purpose is to ensure prevention.

Ninth Means for Solving the Problems The present invention is directed to an active matrix liquid crystal display device (see Figure 1) for preventing short-circuits between storage capacitors and signal wiring. Electrode (5) and drain electrode: This is characterized by providing a layer for protecting the intersecting portion of the electrode (1) (a two-handed conductor film or an insulating film such as a metal or metal oxide film).

(e) Function In the present invention, the insulating film (if there are two protrusions, pinholes, or dust, respectively, CB in FIG. 1), the upper part of the second layer insulating film (4) or the first layer insulating film as shown in (0) (3) and the second layer insulating film (
4) Amorphous silicon 1i1i121 in the intermediate layer with
．． By leaving the ITO film (6) or the Qr film (7), the auxiliary capacitance electrode (51) and the drain electrode (
The thin insulating film at the intersection with 1) is not etched and the conductor 1!
The presence of the film (8) compensates for defects in the insulating film, and no short circuit occurs at the intersection of the auxiliary capacitance electrode (5) and the drain electrode (11).

(to) Example Fig. 1 cA) (: Plan view of a liquid crystal display device using TPT according to an embodiment of the present invention, Fig. 1) 11 is a cross-sectional view of the intersection.

Here, an amorphous silicon film 421 is used as a semiconductor film.
(a-S i) A case will be described in which an O'' film (71) is used as the metal and an ITO film (6) is used as the metal oxide.

Semiconductor thin film (SL-3i) (When leaving 2+? Figure 1C
B) l=indicated.

The auxiliary capacitance electrode (5) is made of ITO (600A), and the third layer insulation film (3) is made of borosilicate glass substrate.
) for 81N! (800A), gate electrode gQr film (
71 (1200A), display electrode'& ITO film (61 (
After forming the second layer insulating film (4) with 5INx (600A) using P-OVD device C2, the semiconductor thin film 9ea-S i (2+500 AS semiconductor thin film for electrode contact &n-a-8i) is formed. (200A) at the same time [;
A-81 (21) and n-5L-31 are connected to the channel part and the drain electrode (11 and the intersection of the gate electrode and 1
:, leaving it at the intersection of the drain electrode (1) (AI! (2000A) and the auxiliary capacitance electrode (5) CITO), and etching the other a-81 (21 and na-8i''4r-etch).

After that, when a drain electrode (11) was formed, short circuits due to dust and defects C: as thick as the insulating layer disappeared.

It goes without saying that C2 can also be applied in the absence of na-a-8i.

The case where a metal or metal oxide film is left is shown in FIG.
: After forming the -th layer insulating film (3), the gate electrode is formed with an Or film (
7) And the display electrode is coated with an I'l'O film (6),
During pattern formation by etching (: C: Simultaneous C) Intersection of drain electrode (1) and auxiliary capacitance electrode (5) (: also gate electrode material or PAf7) (gold!: A) or display electrode material I TOff !+61 (metal oxidation #,'
I) After that, a second layer insulating film (4) and a semiconductor thin film were simultaneously formed using a P-eVD device, and when the drain (1 pole (11) and source electrode were formed, the auxiliary capacitor 'fi electrode (5) and There is no longer a short circuit with the drain electrode (1).

Game here)! Similar results were obtained when both the electrode material and the display electrode material were left at the intersection of the two auxiliary capacitor electrodes (5) and the drain/electrode (1). Naturally,
A semiconductor and a metal compound may coexist.

Here, as an improvement plan that does not increase the current number of processes, a-
8i, Qr, ITO'i' example): Although shown, similar effects can be obtained by using other semiconductor thin films, metals, metal oxides, or conductive polymers (eg, polyaniline).

Insulator of intermediate layer of MIM element (jnsulat;or)
Since the auxiliary electrode and the signal line are also formed in multiple layers, the present invention can be applied to the insulating film at the intersection of the signal line and the auxiliary capacitor (if the two-handed conductor film, metal, or metal oxide is left on the C2). C: By compensating for defects in the insulating film and widening the layer spacing, it is possible to prevent short circuits between the signal wiring and the sleeve support.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the liquid crystal display device of the present invention, and a sectional view of the intersection of the drain electrode and the auxiliary capacitor Jf/L electrode and the intersection of the drain electrode and the gate electrode. FIG. 2 is a plan view of a conventional liquid crystal display device and a sectional view of the intersection of the drain electrode and the auxiliary capacitor Ik electric coffin. (11...Drain electrode, (2+...Amorphous silicon film, (3)...-th layer insulation cavity, (4)...
Second layer insulating film, (5)... Auxiliary capacitance it pole, +61・Z
T O film, (7)...or film, (81...conductive film.

Claims (1)

[Claims] 1. In an active matrix liquid crystal display device, a conductive film or a semiconductor film is provided in a portion where an auxiliary capacitance and a signal wiring are separated by an insulating film. A liquid crystal display device characterized by intersecting conductive films or semiconductor films. 2. The liquid crystal display device according to claim 1, wherein the conductive film is formed of one or more substances selected from the group consisting of semiconductors, metals, metal oxides, and organic substances.