JPS61151615A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent thoroughly the crosstalk between adjacent picture elements and to prevent the exfoliation of a substrate and laminate as well by constituting the top surface of the insulator on the periphery of the laminate and the top surface of the laminate to approximately the same plane and providing electrodes for display elements on the plane. CONSTITUTION:The 1st electrode 21, a non-linear type element 2 and the 2nd electrode 15 are successively laminated on the light transmittable insulating substrate 20 to constitute the laminate 17. An insulator of a photosensitive polyimide resin 29 is formed over the entire surface and the substrate 20 is exposed with UV light from the rear side thereof without using a mask. The non-photosensitive projecting part above the laminate is removed. The top surface of the laminate and the top surface of the insulator are made approximately flush with each other. The part between the picture elements 31 is etched after the formation of the 3rd electrode 23 for display elements connected to the 2nd electrode. The crosstalk between the adjacent picture elements is thus thoroughly prevented and the exfoliation of the substrate and the laminate owing to a difference in thermal expansion is prevented by packing the periphery of the laminate 17 with the resin 29.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application of the Invention The present invention relates to solid-state display devices, image sensors, etc., which solidify display parts of microcomputers, word processors, televisions, etc. by providing a display element, preferably a liquid crystal display panel. Alternatively, the present invention relates to a semiconductor device having nonlinear characteristics that is applied to a liquid crystal printer.

``Prior Art'' For solid-state display panels, a system in which each picture element is controlled independently is effective for large-area displays. A panel using such active elements has 640 elements in the horizontal force direction (640 x 3 = 1920 elements in the case of full color) and 20 elements in the vertical direction.
There is a need for a display device with a large area matrix configuration of 14 format or larger with 0 elements or 526 elements.

However, in such a large-area display device, picture elements (hereinafter also referred to as pixels) each having an active element are arranged in a matrix shape with a predetermined distance between them.

However, the upper surface of one electrode of this pixel is required to be flat for the dubbing process for alignment, especially in liquid crystal display elements. Furthermore, if the electrode has a convex shape, it will peel off from the substrate surface during the dubbing process, causing a decrease in yield, and there is no display panel that completely solves these problems. is the current situation.

[Problems to be Solved by the Invention] In such a large-area display device, in addition to completely eliminating crosstalk between each pixel, peeling of active elements and lead wiring from the substrate is required.
It is extremely important to prevent this.

In addition, particularly in such display devices, in order to achieve a field of view ratio (aperture ratio) of 80% or more, the width of the lead wiring must be approximately 20 μm, and peeling may occur due to the difference in thermal expansion coefficient between the lead wiring and the glass substrate. was more likely to occur. Furthermore, in an active display device, when each pixel and the semiconductor connected to that pixel are made to correspond on a 1:1 basis, four types of photomasks are required in the manufacturing process.

If this photomask is made once, it requires seven steps (resist coating, baking, patterning, development, partial removal of resist, selective etching of the workpiece, and removal of resist), which increases the manufacturing yield. This had become a huge hindrance. For this reason, there has been a demand for a semiconductor device structure in which the number of mask alignments is only one of two types and can completely prevent crosstalk between adjacent pixels.

"Means for Solving the Problem" In order to solve the problem, the present invention provides a non-linear element as a second
It has a semiconductor under the electrode and a first electrode therebelow. The periphery of this nonlinear element is filled with an insulator. By making the upper surface of this insulator approximately coincide with the upper surface of the second electrode (each surface is smoothly continuous), the surface of the pixel (the surface of the third electrode) was made flat.

Further, a liquid crystal electrode (third electrode) is provided in close contact with the second electrode on the non-linear element so as to cover the semiconductor and the insulating material around the semiconductor. (By doing this, dubbing for liquid crystal alignment can be easily performed on the third electrode without inducing peeling of the nonlinear element and leads on the polyimide resin coated on the third electrode.) It became possible to obtain.

Further, the first pixel and the adjacent second pixel are connected in close contact with the glass substrate, with the first electrodes of each pixel extending over the substrate.

As a result, since the self-line process was used for mask alignment, it was possible to align the masks only once (two masks).

The semiconductor is covered with an insulator around its sides (electrodes on the top and bottom),
Passivated. This passivation film also prevents crosstalk between pixels.

The nonlinear element used in the present invention has a pair of electrodes (first
(and second electrode) each have ohmic contact, but are composed of elements having composite diodes that configure reverse rectification characteristics, and a typical example thereof is an N-type semiconductor (Si) doped with hydrogen or a halogen element. - Type I (hereinafter referred to as intrinsic or substantially intrinsic) semiconductor (SixC+-x(0
<X≦1))-N provided by stacking N-type semiconductors (St)
Including semiconductors with an IN structure, that is, an NIN junction in which an Nl junction and an IN junction are electrically connected in opposite directions and integrated as a semiconductor, as well as its variations NN''N, NP
-N, NIPIN, NIP-IN, or NIP''IN structure (hereinafter, for simplicity, these are collectively referred to as NIN type diodes).

Furthermore, in the present invention, the line width of the X wiring or Y wiring (hereinafter referred to as the X wiring as only the X wiring is shown in the drawing) and the width of the nonlinear element on the composite diode and the matrix constituting the matrix are approximately equal to each other. They have the same shape and can be completed with only one mask alignment. A typical example of the structure of the present invention is shown in FIG. 4, and the manufacturing process thereof is shown in FIG.

Furthermore, for a solid-state display device such as a liquid crystal display device, the alternating current bias is connected to the other electrode (fourth electrode) of the liquid crystal, the lead is wired in the Y direction, and the electrical level is controlled to achieve full color and gradation. It also has the feature of being able to be controlled.

``Function'' In this way, even for large-area matrix formation of A4 size or larger, the leads in the X direction can be arranged closely on the insulating substrate in the stripe portion between each pixel.
In addition, it was possible to eliminate electrical leakage from adjacent elements by passivation between each pixel. In addition, the alignment accuracy in the X direction can be improved by ±200 by making the first electrode and the lead connected to it the same width.
The process is now possible with low alignment accuracy of μ or less (theoretically within ±3 rings).

In addition, by passing red (referred to as R), green (referred to as G), and blue (referred to as B) filters to each active element, voltage can be applied independently to that level on the Y axis. . Therefore, it has the feature that it is possible to perform gradations for R, G, and H.

The present invention will be explained below according to examples.

"Example 1" FIG. 1 shows a circuit diagram using the solid state display device of the present invention.

In the drawing, the pixel is the electrode (22) of the nonlinear element (2).
(second electrode), one electrode (23) of the liquid crystal (3) (
a third electrode). The non-linear elements are connected by first electrodes (21) to addresses vA (4), (5) of the X wiring that provides clock signals. On the other hand, liquid crystal (
The fourth electrode (24) in 3) is a data line (6) of Y wiring.

It is connected to (7). Y wiring is another transparent insulating substrate,
Typically, the glass substrate ((20° in Fig. 4(C)
)) are provided correspondingly to each side. And this fourth
The electrode (24) is R (red) (Yl), G (green) (Yz)
, B (blue) (omitted in the Y3 drawing) filter (25)
, (25”) and is fully colored.

This X wiring is connected to the same insulating substrate, typically a glass substrate (fourth
(20) in Figures (B), (C), and (D)
) is provided above. As a result, crosstalk (33
), making it possible to increase the resistance of this part to 10''Ω or more, preferably 1010Ω or more.

Such picture elements are arranged in a matrix, 2×2 in the drawing.
showed that. However, the present invention does not use such a small matrix, but a scaled-up display device, for example (100 pixels).
Effective for large matrix panels such as 100.1920 x 200 or 512).

Examples of the manufacturing process and characteristics of a nonlinear element that is part of a pixel using such a composite diode are shown in Figures 2 and 3.
Shown in the figure.

The manufacturing process shown in FIG. 2 is (30
) is particularly suitable for expanding the manufacturing area.

Figure 2 (A), (B), (C), (D-2
) corresponds to the longitudinal sectional view of FIG. 4 c-c'. FIG. 2 (D-1) corresponds to the longitudinal sectional view taken along line ^-A'' in FIG. 4, and shows the device structure.

In FIG. 2(A), Corning 7059 glass (20) was used as the light-transmitting insulating substrate. On this top surface, a conductive film of aluminum (11) and a chromium film (12) on top of it are deposited by sputtering or electron beam evaporation.
They were formed to a thickness of ~0.5μ and 500-1500μ, respectively. Chrome (500-1500) is added under the aluminum to further promote adhesion to the glass.
may be formed.

After this, N is applied to the entire surface using plasma gas phase reaction method.
IN (including NP-N, NIPIN, NIPI-IN)
A composite diode made of a non-single crystal semiconductor structure was formed. That is, 13.56MH of N-type semiconductor with silane
By performing high frequency glow discharge of 200 to 30
A non-single-crystal semiconductor is formed on a surface of a substrate maintained at 0°C.

Its electrical conductivity is 10-7~10-' (0cm)
- It had a general public and had a thickness of 500 to 2,500 people. Next 1
0-6~10-? The vacuum was sufficiently drawn down to torr.

Silane (StllHz+b*z e.g. 5iHa with m=1
) and DNS (St(C10)s), and if necessary, BtHa is added to form a ■-type non-single crystal semiconductor.
For example, 0.2μ (
7) Thickness: DNS/ (0MS+5iH4) = 1
/80. P as BzHi/SiH* = 7PPM
- type 5ixC+-x was formed.

Further, the vacuum was sufficiently evacuated to 10-b to 10-'torr.

Layer an N-type semiconductor on top of it to a thickness of 50 to 500 to form an NP-N junction of 5L-5ixC1-x (0<X<1)
-5i heterojunction was formed.

Thereafter, chromium (15) for light shielding was laminated as a second electrode on the upper surface by electron beam evaporation or sputtering.

Furthermore, as shown in FIGS. 2(A) and 2(B), anisotropic plasma etching was performed using the first photomask (16) so that the peripheral portion (26) was vertical, and the laminated body (17
) was configured. Next, heat the entire surface to 200°C, for example.
The semiconductor (2) was subjected to thermal oxidation, and silicon oxide was produced by solid phase-vapor phase oxidation. Next, a photosensitive polyimide resin (29) was formed on the entire surface of these by a coating method to a thickness of about 2 μm. Thus, the upper surface of the laminate (17) (
15) and the top surface (39) of the polyimide resin (29) become approximately the same plane after curing (the insulator surface and the laminate surface are smoothly continuous), excluding the convex portion of the laminate (17). I made it happen. For example, 40 to 5 depending on development and curing.
When decreasing by 0x, the thickness of the laminate is approximately 1μ, so approximately 2
The thickness was μ. Next, ultraviolet light (40) was exposed from the back side of the glass substrate (20) using a known mask aligner without using a mask. For example, with Cobilt's aligner, the exposure time was about 2 minutes. Its strength is 300-40
Ultraviolet light with a wavelength of 0 rv (15 to 30 seconds is sufficient for 10 mW/cn+).

Then, as shown in FIG. 2(C), the convex region above the laminate having the side surface of (26), which is in the shadow, is not exposed to light.
Only the area around that side is exposed to light. After further development, the non-photosensitive convex portions were dissolved away using a rinsing solution. Thus the second
Figure (C) was obtained.

Next, do all of this at 180℃ for 30 minutes + 300℃ for 30 minutes +
Cure was performed by heating at 400° C. for 30 minutes in nitrogen. In addition to exposing the second electrode of the non-linear element, which is the upper surface of the laminate, without using a photomask, this upper surface and the surface of the polyimide resin insulator in the peripheral area are made to be approximately on the same plane. It is now possible to configure.

Next, CTF was formed on the entire upper surface of FIG. 2(C) using ITO or tin oxide to a thickness of 0.1 to 0.5 .mu.m. Furthermore, this CTF was selectively etched using a second photomask (3). In addition, this CTF (23) constitutes the electrode of the liquid crystal pixel brush 3 (Fig. 1 (23)''), and using this CTF as a mask, unnecessary semiconductors between pixels (31) are removed (D-1). It was removed as shown in Figure 2 (D-1) and (D-2).

Furthermore, after this, for the (31) side of this semiconductor, (
It is effective to fill a portion of the polyimide resin for forming an alignment film on the insulator CTF similar to 29).

That is, in FIG. 2, a first electrode (21) on a glass substrate (20), a composite diode (2) made of an NP-N or NIN semiconductor laminate, a second electrode (15), and this second A third electrode (23) made of a transparent conductive film was provided in close contact with the electrode so as to cover the semiconductor laminate (2) and the organic resin around the sides.

As a result, the nonlinear characteristics (electrode area 2
0μ×420μ) corresponding to FIG. 2 (the vertical axis shows the absolute value on a log scale).

"Example 2" The configuration of the present invention is shown in FIG. 4, and a plan view (A) and a longitudinal sectional view (B) of the area (1) surrounded by the broken line in FIG.
, (C) and (D) are shown.

Furthermore, Fig. 4 (B), (C), and (D) are (A
) are shown along the lines AA', B-8', and CC', respectively. In addition, Figure 4(C) shows the liquid crystal (3), upper electrodes (6), (7) and substrate (20'').
is also shown, but the other (A) and (B).

(D) shows only the side having nonlinear elements for simplicity.

The manufacturing method of this element is the same as in Example 1.

That is, the first electrode (21) and the leads (4), (5) connected thereto are formed by the first mask (2), and the semiconductor (2) having the same shape and the conductor constituting the second electrode (15) are formed thereon. is constructed with a width of 20μ.

In other words, the electrode area of the nonlinear element is 20μ x 420μ,
One electrical characteristic is shown in FIG.

Further, the side surfaces of the semiconductor and the lower first electrode are filled with organic resin (29), and the upper surface of the organic resin (29) and the upper surface of the second electrode are configured to be approximately the same plane. Next, CTF is formed over the entire surface of the stacked body in close contact with the upper electrode (15). CTF pixels (23
) and (23') were etched and removed (420μ×420μ).

Thus, the second electrode (22) of the first pixel, the electrode (22') of the second pixel next to it, and the lead (4) between them.
) (FIG. 4B) were made to have the same width, a self-line configuration could be achieved even against pattern deviation in the lateral direction (left-right direction in the drawing). In the vertical direction of the drawing, it is sufficient that the second electrode (22) is formed within the upper and lower ends of the electrode (23), and the two semiconductors (22), (22)
The semiconductor is removed from the open grooves (31) between the leads (4).
), (5) are provided closely on the substrate (20). That is, since the two semiconductors (22) and (22') are isolated by the alignment film insulator (34), there is no crosstalk (the equivalent resistance (33) can be effectively reduced to 10"Ω or more). It could be removed as infinity.

Furthermore, the other fourth electrode (24) of the opposing liquid crystal.

(24'), leads (6), and (7) were formed as wiring in the Y direction using another first mask (2).

After that, for each of the wirings in the Y direction, a red filter is applied to this electrode (6), a green filter is applied to the electrode (7), and the adjacent electrode (
(not shown), a blue filter was formed. Thereafter, polyimide (34°) such as PIQ was coated to form a protective film, and the PIQ was subjected to an orientation treatment.

From the above, it is only necessary to use three types of masks to form one active picture element on this surface, and particularly in that case, it has the advantage that only two overlapping masks (one time) are required.

Furthermore, the other opposing insulating substrate (20°) is
After evacuating the gap by a width of μ, a known liquid crystal (10) was sealed.

As a display panel, a reflective plate is then provided for the reflective type, a light source is provided on the back side for the transmissive type, and the peripheral circuits (8) and (9) shown in Figure 1 are arranged on the printed circuit board. The leads of the display element and each lead of the display element were connected in correspondence with each other.

In this way, it has become possible to pattern an active element type panel using only three masks.

``Effects'' As shown above, the present invention has the following advantages:
The number of photomasks required to fabricate the substrate on the side with the active element is only two, and in addition, the electrode area of the nonlinear element (
Even if the current value (when applying a predetermined voltage) deviates up to ±200μ up and down from the center of the rectangular electrode, it also varies by several II to the left and right.
It does not change even if IIl is shifted, has constant nonlinear characteristics, and can prevent variations in the electrical characteristics of active drive over the entire matrix.

It is an alternating current drive system, and has the characteristic that it is easy to control gradations, especially since the threshold value of the diode can be controlled by the process conditions during stacking of semiconductor layers using a gas phase reaction method.

In the present invention, the nonlinear element is a WIN junction or a 5L-
3ixC+-x (0<X<1) -5L junction.

However, on the other hand, a diode ring with multiple PIN junctions in parallel, or BACK-TO-'B with multiple PIN junctions in series.
The present invention is also effective for other nonlinear semiconductor devices having the origin symmetric characteristic shown in FIG. 3 using the ACK method, the WIN (metal-insulating film-metal) structure, and other Zener characteristics or avalanche characteristics.

Since the upper surface of the laminate and the side periphery are filled with organic resin to make the upper surface approximately the same plane, the upper surface of the CTF can be flattened, and alignment processing can be performed uniformly. It became possible to prevent the peeling of the

[Brief explanation of drawings]

FIG. 1 shows a circuit diagram of a liquid crystal display panel of the present invention. FIG. 2 is a vertical sectional view showing the manufacturing process of the composite diode of the present invention. FIG. 3 shows the operating characteristics of the nonlinear element of the composite diode of the present invention. FIG. 4 shows a plan view and a longitudinal sectional view of the display panel of the present invention.

Claims (1)

[Claims] 1. In a solid-state display device in which a plurality of active element type pixels are provided in a matrix on a substrate, a laminate in which a first electrode, a non-linear element, and a second electrode are provided in a laminated manner. and an insulating material is provided around the side of the laminate so that the laminate and its upper surface are substantially on the same plane, and a third electrode of the display element connected to the second electrode is placed on the plane. A semiconductor device comprising: 2. In claim 1, a plurality of pixels arranged in a matrix are arranged such that a first pixel and an adjacent second pixel having the same configuration as the first pixel are separated by a predetermined distance and transparent. 1. A semiconductor device, wherein the semiconductor device is disposed on a photosensitive substrate, and the first electrodes of the first and second pixels are electrically connected by leads extending from each other. 3. A semiconductor device according to claim 1, wherein the third electrode is provided to constitute a substantially flat plane.