JPS58190041A - Preparation of drive circuit substrate for display device - Google Patents

Abstract

PURPOSE:To effectively prevent inter-layer short-circuit between multi-layer wirings and accordingly improve yield of display panel and also reliability by converting short-circuit defect between multi-layer wirings to open defect and by solving such defect in the comparatively initial stage of the manufacturing processes. CONSTITUTION:The Al film is vacuum-deposited in the thickness of 1,500Angstrom on a glass substrate 21 and the first electrode wiring which also concurrently operates as the gate electrode of thin film transistor and address line 221 and a ground line 222 which also concurrently operates as the one electrode of capacitor are formed by patterning said Al film. The SiO2 film 23 is etched by the ammonium fluoride and a substrate is then dipped into the 10% rare fydrochloric acid solution for partly removing the earth line 222 by etching. Thereafter, undoped amorphous silicon (a-Si) silm 24 is deposited in the thickness of 3,000Angstrom and patterning is carried out by the CDE in such a manner as said film is left only in the element region. A drive circuit substrate can be completed by forming the second electrode wiring which also concurrently operates as the source electrode of a thin film transistor and the data line 251 and the drain electrode which operates as a capacitor electrode 252 by patterning laminated film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a manufacturing method C of a driving circuit board for a liquid crystal display device or the like including a membrane transistor array and a multilayer wiring structure.

[Technical background of the invention and the points between them]

Recently, display panels using thin film transistor arrays have been researched in various places (for example, IE h4 W
'1Transactions on l1ilect
Ron Devicaa.

vol, fm-20, no, 11. November
r 197L p 995-] (Refer to 101) 0 Figure 1 is an equivalent (b) circuit of a display panel using a general thin film transistor array oIIC11@5J
jl *・-t J n ) is an address line that drives the gate electrodes of the # film transistors 13 in the row direction in common C, 12()J , / 2B , -, 12m
) transfers the Denubray signal to the thin film transistor No. 3 in the column direction.
The thin film transistor 13 is connected to each cross point of the address line 11 and the cheater line 12 (≦2 phases for each corresponding pixel, and each drain electrode is connected to the capacitor 14 (- is also connected to The display element 15 is, for example, a liquid crystal or an electroluminescent element. Taking a liquid crystal display panel as an example, a drive circuit including an address line 1, a data line 12, a transistor 3, and a capacitor 14f is integrated. The entire surface of the substrate and the transparent electrode facing it
This type of display panel is constructed by sandwiching two liquid crystal panels with a modified substrate and is driven in a line-sequential manner in which data is written in each address line.
Display element #5 has a duty ratio of almost 100% #JFA!
By the way, if this camphor display is to be realized in detail or in a dog-faced display, the number of transistors will be very large. For example address 200X Chi 5'200or
In this case, 40,000 elements are required, and the number of cross points of data lines, address lines, and capacitors are also 40 if (10 and 7) respectively. It is extremely difficult to manufacture well.The main causes of defects are ■ between multilayer interconnections or capacitors (1).
Q: Possible causes include short circuit, open wiring, defective transistor, etc.0However, if there is a point defect in the display and fabrication is allowed, open wiring and defective transistors are usually defects, so it is not a major problem. For example, in Figure 1 (in Figure 1, even if the address line 11 is cut off at one point on the way, it is possible to input signals from both directions). This is because all the pixels are expected to operate normally depending on the order of magnitude.

On the other hand, a short circuit between multilayer wiring is not just a point defect, and has a big impact on the display f2.Moreover, it is possible to separate the short circuit position using a laser, etc., but for this reason, C- You need to know this, and this is different from the open check.It takes m1 when the horizontal position (second crawling dog).In addition to the address line and cheetah line songs,
Including the short-circuit check of the capacitor, the process of zero-resetting, straightening, and short-circuiting, which is extremely inefficient, is also included, so a decrease in productivity can be avoided. Short-circuit defects are caused by the fact that the interlayer insulating film, unlike the thermal oxide film of crystalline silicon, must be formed at low temperatures by sputtering or CVD, and its film quality is extremely poor, especially in displays. [Object of the Invention] This invention solves the above-mentioned problems of the conventional technology.

It is an object of the present invention to provide a method for manufacturing a drive circuit board for a display device that can effectively prevent short circuits between layers of multilayer wiring to improve the yield and reliability of display panels. [Summary of the Invention] The present invention converts short-circuit defects between multilayer interconnections into open defects, which significantly impairs the productivity of drive circuit boards containing thin film transistor arrays and multilayer interconnections.

Also, countermeasures should be taken at a relatively early stage of the manufacturing process.
], If there are a large number of converted open defects, the production of that sample is stopped to avoid wasteful production. That is, in the present invention C-, after forming the first electrode wiring C1 on the insulating substrate and covering the entire surface with an interlayer insulating film, the second electrode wiring is formed on the insulating substrate.
Before forming the electrode wiring, the entire surface of the substrate is etched with an etching solution of the first electrode wiring material. 1 by removing the electrode wiring material.

1st. According to the present invention C2, short circuits between multilayer wiring layers can be effectively prevented, thereby improving the yield and reliability of display panels. In addition, in the present invention f-, it is much easier to inspect the sample after the etching process and find out the extent of the pinholes than to find the pinholes in the interlayer insulating film U before the etching process. (= easy (two and exact (′-
can be done. This is because a glass substrate is normally used for this type of drive circuit board, and when the first electrode wiring in the pinhole portion is etched, this portion becomes transparent. Therefore, it is easy to judge whether or not to proceed with this sample to the next step C2 based on the pinhole depth #i.
It is possible to eliminate unnecessary processes and significantly improve the productivity of the drive circuit board.

[Embodiments of the invention]

FIGS. 2(a) and 2(b) are a plan view showing one pixel portion of a driving circuit board of a liquid crystal display device manufactured according to Example C- of the present invention, and a sectional view thereof taken along line AA'. To explain the manufacturing process, first, heat the 150 OA thick Atl1!1 on the Galanu substrate 2 and pattern it to form the thin film transistor which is the first electrode. $i! li
◎After this, form the ground line 22□ which also serves as the 10,000 electrodes of the address line 22 pacita.◎After this, the RI-
Sputtering method or CVD method (Yuyo 113 (it) OA
0r8i(J, deposit the film 23 on the entire surface (2). This 81(
J, the film 23 serves both as a gate insulating film of a thin film transistor and as an interlayer insulating film for wiring. After that, this 810. The film 23 is etched with ammonium fluoride for about 15 seconds, and then the substrate is immersed in a 10% dilute hydrochloric acid solution for about 3 minutes.
5i (J, When there is a pinhole 26 like the film 23 (U in Figure 2), the ground line 22□ below it is partially etched away. ◎After this, the substrate temperature is 250°C.
)1. From Kaburo release decomposition method C2, undoped 0
] Amorphous silicon (a-sl) film 24 is
0OA is deposited and this is left on top of the element (2σ) (2C).
Patterning is done using DEI. And M with a thickness of 500A. Then, the At film with a thickness of 6000 A was steamed, and these laminated films were patterned to form the source electrode/data line 25 of the thin film transistor, which is the second electrode wiring, and the drain electrode/capacitor electrode 252. According to this embodiment, the driving circuit board is completed by the etching process after the formation of 810*$z3, which is one interlayer insulating film.

8i (J) By removing the first electrode wiring in the pinhole portion in the film 23 C2, a short circuit between the first and second electrode wirings is prevented.

The effects of the present invention are clearly demonstrated by specific data. The samples that followed the process of the above example were referred to as group A, and the samples that followed the process of the above example were referred to as group A, and the samples that followed the same process as in the example above were used as group B, and 87 like the above Example 1/J
0. C is the one that was not subjected to etching treatment after film formation.
Characteristics were evaluated as a group. ◎ The drive circuit board has a thin film transistor array section of 10 x 10 d, and the number of lungs is 50 rows x 50 columns = 2500 (pixels).

The size of one pixel is 2 (10 x 200 μm).The table below shows the number of open address lines out of 50 address lines, with 10 samples in each group A, B, and C. The average value for each group and the number of samples in which the address line and cheetah line were short-circuited are shown.

As is clear from the table, short-circuit defects in multilayer interconnections are significantly reduced by Method I2 (according to the present invention). First electrode wiring
Etching with an etching solution (2) It is clear from comparing A and B that the interlayer insulating film is etched in advance. It is clear that a sufficiently large effect can be obtained without performing an etching process.

10,000, it can be seen from the table that the number of address line open (disconnection) defects is increasing◎However, as mentioned above, this defect
2. iJ point defect C due to method B of extracting electrode wiring from the substrate
Two conversion measures are possible. In other words, after mounting the liquid crystal, you can visually check the location of the open defect in the display state, and countermeasures can be taken by wiring the address line that is open (or wiring to supply drive signals from both sides). I),
It is not a problem.

As described above, according to the present invention, it is possible to greatly improve the problem of interlayer short circuits in multi-layer interconnects (2), which had previously significantly reduced productivity, and to detect defective boards at a relatively early stage of the manufacturing process (2). Therefore, wasteful manufacturing can be reduced, and the productivity of the display device drive circuit board can be greatly improved. Note that the present invention is not limited to the above-mentioned Example C2.

Semiconductor materials for thin film transistors.

A-ail limited II-Vl group Cd8e, Cd
8° or a material such as Te (the interlayer insulating film is 8°
i (not limited to J, l1, first + [i 'electrode wiring erating solution C- as long as it is not etched, it may be an insulating film of Si, N, etc.11!). The south pole wiring material is not limited to Al2, but other metal materials and transparent electrode materials can be used.

[Brief explanation of the drawing]

FIG. 1 is an equivalent circuit diagram of an S-film transistor array for driving a display device, and FIGS.
-A' sectional view. 2 No. Glass substrate, 22. ...Gate terminal and address line, 22. ... Capacitor electrode/ground line, 23...51 (J, film (gate insulating film/interlayer insulating film) 24... a-8i film, 25I... Source electrode/data line, 26...・Drain (magnetic pole and capacitor) atria 26...Pinhole〇Applicant's agent Takehiko Suzue 2 Figure 1 1i2 (a) (b)

Claims (1)

[Scope of Claims] (1) When manufacturing a drive circuit board on which a display concentrator drive circuit including two thin film transistor arrays and multilayer wiring is integrated, an insulating substrate C (1 first After forming the electrode wiring and covering the entire surface with a J-open fiber edge film, a step of etching the entire surface of the C-5 substrate before forming the second electrode wiring with an etching solution of the first electrode wiring material is provided. A method for manufacturing a drive circuit board for a display device, characterized in that (
2) The display element is a liquid crystal display element, and the first electrode wiring is an address line that commonly connects the gates of the thin film transistors in the row direction, and a ground line that serves as the electrode of 10,000 capacitors provided in pairs with each thin film transistor. According to claim 1, the second electrode wiring is a cheater line that commonly connects the sources of the #transistors in the column direction and the other electrode of the SiJ capacitor that also serves as the drain electrode of each AI conversion transistor. A method for manufacturing a drive circuit board for a display device. (3) The interlayer insulating film is made of 8IO1 by sputtering method or CVD method C2 which also serves as the gate insulating film of the thin film transistor.
A method for manufacturing a display device drive circuit board according to claim 1, which is a film.