CN1716057A

CN1716057A - Method for producing liquid crystal display base board

Info

Publication number: CN1716057A
Application number: CN 200510088284
Authority: CN
Inventors: 周文彬; 杨克勤
Original assignee: Quanta Display Inc
Current assignee: AU Optronics Corp
Priority date: 2005-08-03
Filing date: 2005-08-03
Publication date: 2006-01-04
Anticipated expiration: 2025-08-03
Also published as: CN100449384C

Abstract

The production process of base board of LCD includes the following steps: providing base board with transparent electrode layer and metal layer; developing partially; etching the photoresist layer and the base board with transparent electrode layer and metal layer, defining signal scanning lines, film diode area with interval, pixel area and electrode wires; and forming oxide layer on partial surface of the metal layer to fill the interval in the film diode area. The production process of the base board of LCD includes patterning to etch the mask sheet and other steps, and has high product quality and efficiency.

Description

The manufacture method of liquid crystal display base board

Technical field

The present invention relates to a kind of manufacture method of liquid crystal display base board, relate in particular to a kind of manufacture method that is applicable to the thin film diode multiple substrate.

Background technology

Active-matrix liquid crystal display has been the main flow of flat-panel screens now, in the manufacture method of known plurality of groups of substrates of thin-film transistor, five road mask plates (photoetching etching) technology more commonly, the thin film transistor (TFT) active base plate of main flow needs four to six road mask plates, also have to propose to be less than the disposal route of four road mask plates, but do not obtain the checking of volume production as yet; And the another kind of active-matrix liquid crystal display substrate is selected, be to utilize thin film diode, cooperate two selection wire (DSD, dual-select-diode) driving method, can become the active base plate that another kind has potentiality, and compare with thin film transistor (TFT), thin film diode has simpler processing procedure, and equipment investment is more economical.

Along with the direction of LCD towards the large scale manufacturing develops, will face many problems, for example acceptance rate reduces and production capacity descends or the like.If therefore can reduce the employed mask plate number of thin film diode technology, then can reduce the exposure process number of times that the thin film diode device is made, just can reduce manufacturing time, increase production capacity, and then reduce manufacturing cost.

With the insulation course is silicon nitride (SiN _x) thin film diode be example, modal processing step needs the processing of three road mask plates, wherein the first road mask plate prepares the pattern of metal conducting layer and thin film diode lower metal; The second road mask plate prepares the pattern of thin film diode insulation course; The 3rd road mask plate is then prepared viewing area and thin film diode upper strata metal pattern, and the top view of the product after the preparation wherein represents to have signal scanning line S1, S2, thin film diode 100 and viewing area 200 respectively as shown in Figure 1; And in JP08-320495 a case, disclose a kind of anodizing of utilizing, on tantalum metal layer, carry out oxidation and form Ta ₂O ₅Layer as the insulation course in the middle of the thin film diode, thereby can only be utilized the twice mask plate just can prepare the method for thin film diode.

Yet the disposal route in past prepares thin film diode needs two to three roads to handle the mask plate number at least, just can finish structures such as thin film diode, if just can finish preparation with simple one mask plate, will more can improve acceptance rate and production capacity.

Summary of the invention

The invention provides a kind of manufacture method of liquid crystal display base board, utilize patterning (Patterning) technology such as photoetching, etching of one mask plate, finish the manufacturing of liquid crystal display base board, the effect of the acceptance rate that is improved simultaneously and production capacity.

The manufacture method of liquid crystal display base board of the present invention may further comprise the steps: (a) provide the substrate with transparent electrode layer and metal level, and transparent electrode layer is between metal level and substrate; (b) form photoresist layer, and photoresist layer has at least the first thickness and second thickness with pattern; (c) etching photolithograhic glue-line and have transparent electrode layer and the substrate of metal level, definition signal sweep trace and thin film diode zone, and pixel region and electrode cable respectively, and the thin film diode zone has the gap; And (d) form oxide layer form oxide layer on the part surface of metal level, and oxide layer is filled up the gap in thin film diode zone.

Transparent electrode layer on the substrate in the manufacture method of the present invention can be use always any, is preferably indium tin oxide (ITO) or indium-zinc oxide (IZO); Metal level on the substrate can be use always any, is preferably tantalum metal layer; Generation type in the step of the present invention (b) is not limit, and preferably mask plate or the diffraction mode with shadow tone (half-tone) forms; In addition, corresponding this signal scanning line and this thin film diode zone of forming of first thickness in step (b).

In step of manufacturing of the present invention (c), with the method for etching definition signal sweep trace and thin film diode zone and pixel region and electrode cable, can be any one engraving method, be preferably dry ecthing or wet etching, as use wet etching, then after carrying out, wet etching also can comprise O ₂Ashing method is to obtain complete etched effect; Simultaneously, signal scanning line and thin film diode zone, and the sequencing that pixel region and electrode cable etc. form is unrestricted, is preferably after the structure that forms signal scanning line and thin film diode, just forms pixel region and electrode cable; So the terminal line of electrode cable splicing ear portion, and the terminal line electrical connection is positioned at mutually plain extra-regional portion of terminal link block IC zone thus.

In manufacture method step of the present invention (d), the mode that oxide layer forms can be known any one, preferably form with anodizing, and the scope that forms is filled up the gap in thin film diode zone, to connect the metal-layer structure of two thin film diodes, form the structure of metal level-insulation course-metal level (metal-insulator-metal); In addition, oxide layer in step (d) is because the composition of metal level is different and variant, and in one embodiment of the invention, oxide layer is tantalum oxide (Ta ₂O ₅).

The accompanying drawing summary

Fig. 1 is the synoptic diagram of known film diode structure;

Fig. 2 (a)-(f) is the top view of the preferred embodiment of the present invention;

Fig. 3 (a)-(f) is the diagrammatic cross-section of the preferred embodiment of the present invention.

Embodiment

Bound fraction exposure technique of the present invention, etching and anodizing are carried out patterned process, finish the manufacturing of liquid crystal display base board with the simple process of one mask plate; One of the available method of partly exposing is the intermediate tone mask plate, comprise complete exposure region, half exposure district and non-exposed area, the non-exposed area is corresponding to the zone that will form than thick photoresist, half exposure district then corresponding to will form depressed part, than the zone of thin photoresist.

Fig. 2 (a) to Fig. 2 (f) be the top view of each step of present embodiment, and Fig. 3 (a) is the sectional view that indicates I → I ' among Fig. 2 to Fig. 3 (f), wherein be formed with A respectively in I → I ' line segment, B, C and D four zones below will illustrate the manufacture method of liquid crystal display base board of the present invention the while with reference to Fig. 2 and Fig. 3.

At first on glass substrate 00, plate one deck ITO layer 10 and tantalum metal layer 20, shown in Fig. 2 (a) and Fig. 3 (a), apply the spot function that exposes with part after the photoresist 50 and carry out exposure imaging, this moment, the mask plate pattern of ITO pixel region B and electrode cable A was the part exposure, perhaps, utilize diffraction principle to design the pattern in described two zones, also can reach the part exposure effect through after the exposure imaging, cause photoresist 50 thickness of ITO pixel region B and electrode cable A to have only 1/2nd to 1/3rd of normal pattern photoresist thickness such as signal scanning line (gate line) C and thin film diode D, shown in Fig. 2 (b) and Fig. 3 (b).

Then carry out etching, carry out partially-etched to ITO layer 10 and tantalum metal layer 20, zone with definition signal sweep trace C and thin film diode D, and because the photoresist thickness of ITO pixel region B and electrode cable A is just thinner originally, so through etching, the photoresist that originally is deposited in ITO pixel region B and electrode cable A also will be removed fully, and the zone of thin film diode D also is etched into has the gap, to mark off two zones, become two electrode D1 of thin film diode, D2 is shown in Fig. 2 (c) and Fig. 3 (c); If this step is to utilize the mode of wet etching to carry out, then can add one O in addition again ₂Ashing method is to guarantee to get rid of the photoresist of ITO pixel region B and electrode cable A.

Then carry out the etching second time after finishing etching for the first time, remove the tantalum metal layer 20 of ITO pixel region B and electrode cable A, stay ITO layer 10, with definition ITO pixel region B and electrode cable A, shown in Fig. 2 (d) and Fig. 3 (d).

Remove all photoresists, promptly finish two electrode D1, D2 of all pixel electrode B, electrode cable A, signal transducting wire C and thin film diode region D, shown in Fig. 2 (e) and Fig. 3 (e).

At last substrate 00 is fed DC voltage, tantalum metal layer 20 is carried out anodic oxidation, to form oxide layer Ta at signal call wire C and as upper surface and the side of the electrode D1 of thin film diode D ₂O ₅25, and this oxide layer Ta ₂O ₅25 generation touches tantalum metal layer 20 as another electrode D2 of thin film diode D with extension, and promptly finish Ta/Ta at thin film diode D this moment ₂O ₅The structure of/Ta is shown in Fig. 2 (f) and Fig. 3 (f).

Non-display area 500 is represented in the left side of Fig. 2 (f) middle conductor X-Y, and the terminal line 501,502 of this non-display area 500 extends connection by electrode cable A respectively, and is electrically connected to portion of terminal link block IC zone (figure does not show).

The foregoing description only is to give an example for convenience of description, and the interest field that the present invention advocated should be as the criterion so that claims are described, but not only limits to the foregoing description.

Claims

1, a kind of manufacture method of liquid crystal display base board may further comprise the steps:

(a) provide substrate, and described transparent electrode layer is between described metal level and described substrate with transparent electrode layer and metal level;

(b) form photoresist layer, and this photoresist layer has at least the first thickness and second thickness with pattern;

(c) this photoresist layer of etching and have transparent electrode layer and the described substrate of metal level, difference definition signal sweep trace and thin film diode zone, and pixel region and electrode cable, wherein said thin film diode zone comprises described transparent electrode layer and described metal level, and described thin film diode zone has the gap; And

(d) on the part surface of described metal level, form oxide layer, and described oxide layer is filled up the described gap in described thin film diode zone.

2, manufacture method according to claim 1, wherein in step (a), described transparent electrode layer is indium tin oxide (ITO) or indium-zinc oxide (IZO).

3, manufacture method according to claim 1, wherein in step (a), described metal level is a tantalum metal layer.

4, manufacture method according to claim 1, wherein step (b) forms with shadow tone or diffraction mode.

5, manufacture method according to claim 1 is wherein in corresponding described signal scanning line and the described thin film diode zone of forming of first thickness described in the step (b).

6, manufacture method according to claim 1, wherein in step (c), described etching step is dry ecthing.

7, manufacture method according to claim 1, wherein in step (c), described etching step is a wet etching.

8, manufacture method according to claim 7 wherein also comprises O after described wet etching ₂Ashing method.

9, manufacture method according to claim 1, wherein in step (d), described oxide layer forms with anodizing.

10, as manufacture method according to claim 1, wherein in step (d), described oxide layer is tantalum oxide (Ta ₂O ₅).