CN1315148C - Electrode substrates for flat panel displays - Google Patents

Abstract

An electrode substrate of a flat panel display comprises a substrate, an electrode layer, a conductive layer and a protective layer. Wherein, the electrode layer is formed on the substrate; the lead layer is formed on the electrode layer and is made of silver (more than 99.5%), silver alloy, aluminum (more than 99.5%), aluminum alloy, copper (more than 99.5%) or copper alloy; the protective layer is formed on the conductive wire layer and is made of titanium, titanium alloy, molybdenum, chromium, silicon oxide or titanium oxide.

Description

Electrode substrates for flat panel displays

technical field

The present invention relates to an electrode substrate, in particular to an electrode substrate of a flat panel display.

Background technique

As shown in Figure 1, the electrode substrate 4 of the flat panel display used at present has a substrate 41, an electrode layer 42 and a wire layer 43, the electrode layer 42 is formed on the substrate 41, and the wire layer 43 is formed on the electrode layer 42 . Wherein, the material of the wire layer 43 is selected from low-resistivity metals or alloys thereof, such as silver (>99.5%), silver alloy, aluminum (>99.5%) or aluminum alloy, etc., which are commonly used.

In the manufacturing process of the flat panel display, it uses an etchant to etch the wire layer 43 in the electrode substrate 4 into the pattern of the actually required conductive wire or the pattern of the auxiliary conductive wire. As shown in Figure 2A, at first, a photoresist layer 5 is formed on the wire layer 43 (such as silver alloy), and then a photomask 6 with a pattern is arranged on the photoresist layer 5, and an ultraviolet ray is irradiated at the same time. Light (UVlight), followed by a developing step, and finally, etching with an etchant, so that the wiring layer 43 is etched into the pattern of the desired conductive lines, as shown in FIG. 2B.

At present, before forming the photoresist layer 5, the industry will use ultraviolet light (UV light) to clean the surface of the wiring layer 43, the purpose of which is to increase the adhesion between the photoresist layer 5 and the wiring layer 43, and further avoid the photoresist. The layer 5 and the wire layer 43 are peeled off in subsequent steps, resulting in a decrease in the yield of the device.

However, the wiring layer 43 is prone to oxidation (blackening) due to the irradiation of ultraviolet light, which also causes the resistance value of the wiring layer 43 to increase and the adhesion between the wiring layer 43 and the photoresist layer 5 to decrease. In addition, since the thickness of the wiring layer 43 is about 4000-6000 Ȧ, when the etching step is performed, the shape of the etched conductive line is not easy to control, that is, the etching amount of the wiring layer 43 near the photoresist layer 5 will be larger than that of the wiring layer. 43 bottom layer (the part close to the electrode layer 42) has a large amount of etching (as shown in FIG. 2B ), so that electron migration (electronmigration) is prone to occur between the bottoms of adjacent conductive lines, thereby causing short circuit (arcing) and reduce component reliability.

Generally used actively driven flat panel displays (such as AM-LCD) use metal conductive wires mostly alloys of some transition metals such as manganese (Mo), chromium (Cr) or tantalum (Ta). When making these metal conductive wires, the film deposition thickness should not be too thick in order to obtain better film step-coverage. However, a thin metal conductive wire will increase the resistance of the conductive wire, resulting in a larger RC-delay of the signal. Therefore, the size of flat display panels made of these transition metals will be limited. Therefore, in order to manufacture a large-size flat panel display panel, it is necessary to develop a metal conductive line process or material with ultra-low resistance.

From the point of view of the metal conductive wire manufacturing process, in order to obtain a lower resistance value, a thicker and wider metal film must be used. However, the disadvantages of thick metal films are poor adhesion and pinhole formation. Although it is currently improved by using a special bevel etching (taper etching) process, this will lead to an increase in the cost of the process. What's more, a wider metal film not only reduces the aperture ratio of the pixel but also increases the parasitic capacitance of the conductive line. Therefore, a thicker and wider metal thin film process is not feasible.

In the manufacturing process of TFT-LCD (Thin Film Transistor Liquid Crystal Display), although the three-layer metal structure of chromium/aluminum/chromium or molybdenum/aluminum/molybdenum is used as the material of the conductive line, the above-mentioned problems can be avoided. However, in the manufacture of such conductive lines, two different etching solutions must be used. At the beginning, first use the first etching solution to etch the upper layer of chromium (molybdenum) metal, then use the second etching solution to etch the middle layer of aluminum metal, and finally use the first etching solution to etch the lower layer of chromium (molybdenum) metal, that is, it must be carried out three times. The etching steps are not only complicated, but also increase the overall cost, which is not suitable for practical industrial applications.

Because of this, the inventor, in the spirit of active invention and innovation, desperately thought of an "electrode substrate for flat-panel displays" that could solve this problem.

Contents of the invention

In view of the above problems, the object of the present invention is to provide an electrode substrate of a flat-panel display with a protective layer, which can protect the wiring layer so that the wiring layer is not easily oxidized, and can also control the shape of the etched conductive lines.

Therefore, to achieve the above object, an electrode substrate of a flat panel display according to the present invention includes a substrate, an electrode layer, a wire layer and a protective layer. Wherein, the electrode layer is formed on the substrate; the wire layer is formed on the electrode layer, and the material of the wire layer is silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, copper (>99.5%) ) or copper alloy; the protective layer is formed on the wire layer, and the material of the protective layer is titanium or titanium alloy.

To achieve the above purpose, an electrode substrate of a flat panel display according to the present invention includes a substrate, an electrode layer, a wire layer and a protective layer. Wherein, the electrode layer is formed on the substrate; the wire layer is formed on the electrode layer, and the material of the wire layer is silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, copper (>99.5%) ) or copper alloy; the protection layer is formed on the wire layer, and the material of the protection layer is molybdenum, chromium, silicon, silicon oxide or titanium oxide.

To achieve the above purpose, an electrode substrate of a flat panel display according to the present invention includes a substrate, an electrode layer, a conductive line pattern and a protective layer. Wherein, the electrode layer is formed on the substrate; the conductive line pattern is formed on the electrode layer, the conductive line pattern has at least one conductive line, the angle between the side of the conductive line and the electrode layer is about 90 degrees, and the material of the conductive line pattern It is silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, copper (>99.5%) or copper alloy; the protective layer is formed on the conductive line pattern.

Flat panel displays include but are not limited to an organic electroluminescence (OEL) display, an inorganic electroluminescence (EL) display, a light emitting diode (Light Emitting Diode, LED) display, a liquid crystal display (Liquid Crystal Display, LCD) , Plasma Display Panel (PDP), Vacuum Fluorescent Display (VFD), Field Emission Display (Field Emission Display, FED) and Electro-chromic Display (Electro-chromic Display), etc.

Based on the above, the electrode substrate of a flat panel display of the present invention has a protective layer for protecting the electrode layer. Compared with the prior art, the protection layer of the present invention can prevent the wiring layer from being oxidized due to ultraviolet light, thereby reducing the rise of the resistance value of the wiring layer, and at the same time increasing the adhesion to the photoresist layer. Moreover, the present invention can control the shape of the conductive line after etching (such as the angle between the side of the conductive line and the electrode layer is about 90 degrees), avoiding the electron migration caused by the deformed conductive line, and also avoiding the occurrence of short circuit , to further ensure the reliability of components. In addition, when the protective layer is made of titanium or titanium alloy, since a single etching solution can be used, only a single etching step is required to simultaneously etch the protective layer and the electrode layer. Furthermore, the present invention not only has a simple manufacturing process, but also does not increase the overall cost, which is very suitable for practical industrial applications.

The electrode substrate of the flat panel display according to the preferred embodiment of the present invention will be described in detail below with reference to the relevant drawings.

Description of drawings

Fig. 1 is a schematic diagram of a known electrode substrate;

FIG. 2A and FIG. 2B are a group of cross-sectional schematic diagrams for forming conductive lines or auxiliary conductive line patterns on the electrode substrate;

3 is a schematic diagram of the electrode substrate in the first embodiment of the present invention;

4 is a schematic cross-sectional view of forming conductive lines or auxiliary conductive line patterns on the electrode substrate in the first embodiment;

5 is a schematic diagram of an electrode substrate in a second embodiment of the present invention; and

FIG. 6 is a schematic diagram of an electrode substrate in a third embodiment of the present invention.

Explanation of symbols in the figure

1 electrode substrate

11 Substrate

12 electrode layer

13 wire layer

13' conductive wire

14 protective layer

2 electrode substrate

21 Substrate

22 electrode layer

23 wire layer

24 layers of protection

3 electrode substrate

31 Substrate

32 electrode layer

33 conductive thread pattern

331 conductive thread

34 protective layer

4 electrode substrate

41 Substrate

42 electrode layer

43 wire layer

5 photoresist layer

6 mask

Detailed ways

As shown in FIG. 3 , an electrode substrate 1 of a flat panel display according to the first embodiment of the present invention includes a substrate 11 , an electrode layer 12 , a wire layer 13 and a protection layer 14 . Wherein, the electrode layer 12 is formed on the substrate 11; the wire layer 13 is formed on the electrode layer 12; the protection layer 14 is formed on the wire layer 13, and the material of the protection layer 14 is titanium or titanium alloy.

In this embodiment, the substrate 11 may be a flexible substrate or a rigid substrate. Meanwhile, the substrate 11 can also be a plastic substrate or a glass substrate. Wherein, the flexible substrate and the plastic substrate can be a polycarbonate (polycarbonate, PC) substrate, a polyester (polyester, PET) substrate, a cyclic olefin copolymer (cyclic olefin copolymer, COC) substrate or a metal chromate substrate. Material-cycloolefin copolymer (metallocene-basedcyclic olefin copolymer, MCOC) substrate.

In addition, as shown in FIG. 3 , the electrode layer 12 is formed on the substrate 11 . In this embodiment, the electrode layer 12 is formed on the substrate 11 by sputtering or ion plating. Here, the electrode layer 12 is usually used as an anode and its material is usually a transparent conductive metal oxide, such as indium tin oxide (ITO), aluminum zinc oxide (AZO) or indium zinc oxide (IZO).

Referring to FIG. 3 again, the wire layer 13 in this embodiment is formed on the electrode layer 12, wherein the material of the wire layer 13 can be silver (>99.5%), silver alloy, aluminum (>99.5%) or aluminum alloy. Because silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, copper (>99.5%) or copper alloy have low resistance value and high conductivity, they are very suitable as wires. Here, the thickness of the wiring layer 13 is about 4000˜6000 Ȧ.

In addition, referring to FIG. 3 again, the protection layer 14 of this embodiment is formed on the wiring layer 13 . Here, the protection layer 14 is used to protect the wire layer 13 so that the wire layer 13 will not be oxidized when irradiated with ultraviolet light. Wherein, the material of protective layer 14 can be titanium or titanium alloy, because titanium and titanium alloy are active metals, after protective layer 14 is patterned, the bonding degree between protective layer 14 and IC will be than wire layer 13 (silver alloy) The bonding between itself and the IC should be better. In addition, a thin and dense oxide layer (titanium oxide) can be formed on the surface of titanium, and this dense oxide layer is a passivation material with good corrosion resistance. Here, the passivation layer 14 has a thickness less than about 100 Ȧ.

In this embodiment, the thicknesses of the wire layer 13 and the protective layer 14 can be adjusted according to actual conditions.

When forming conductive line patterns or auxiliary conductive line patterns on the electrode substrate 1 of a flat-panel display, a photoresist layer is first formed on the protective layer 14, then a photomask with a pattern is arranged on the photoresist layer, and a photoresist is irradiated at the same time. ultraviolet light. Next, a developing step is performed to form a patterned photoresist layer. Finally, etching is performed using an etchant.

As shown in Figure 4, in this embodiment, when factors such as the thickness of the protective layer 14 and etching parameters are properly regulated, the shape of the conductive line 13' formed after the etching of the conductive layer 13 can be controlled, such as the conductive line 13' The included angle with the electrode layer 12 is about 90 degrees, which can avoid short circuit caused by electron migration between the bottoms of the conductive lines 13 ′. In addition, when performing the etching step, the protection layer 14 and the wire layer 13 can be etched simultaneously by using a single etching solution, that is, the protection layer 14 and the wire layer 13 can be etched simultaneously only by performing one etching. In addition, other patterns can also be formed on the electrode substrate 1 in the same manner.

In addition, as shown in FIG. 5 , an electrode substrate 2 according to the second embodiment of the present invention includes a substrate 21 , an electrode layer 22 , a wire layer 23 and a protection layer 24 . Wherein, the electrode layer 22 is formed on the substrate 21; the wire layer 23 is formed on the electrode layer 22, and the material of the wire layer 23 is silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, Copper (>99.5%) or copper alloy; the protection layer 24 is formed on the wiring layer 23, and the material of the protection layer 24 is molybdenum, chromium, silicon, silicon oxide or titanium oxide.

The features and functions of the substrate 21 , the electrode layer 22 and the wire layer 23 in this embodiment are the same as those of the same components in the first embodiment, and will not be repeated here.

Except that the protection layer 24 in this embodiment is made of molybdenum, chromium, silicon, silicon oxide or titanium oxide, other features and functions are the same as those of the protection layer 14 in the first embodiment, and will not be repeated here.

In addition, as shown in FIG. 6 , an electrode substrate 3 according to the third embodiment of the present invention includes a substrate 31 , an electrode layer 32 , a conductive line pattern 33 and a protection layer 34 . Wherein, the electrode layer 32 is formed on the substrate 31; the conductive line pattern 33 is formed on the electrode layer 32, the conductive line pattern 33 has at least one conductive line 331, and the angle between the side of the conductive line 331 and the electrode layer 32 is about 90°. degree, and the material of the conductive line pattern 33 is silver (>99.5%), silver alloy, aluminum (>99.5%), aluminum alloy, copper (>99.5%) or copper alloy; the protective layer 34 is formed on the conductive line pattern 33 superior.

The features and functions of the substrate 31 and the electrode layer 32 in this embodiment are the same as those in the first embodiment, and will not be repeated here.

In addition, the features and functions of the conductive line pattern 33 in this embodiment are the same as those of the conductive line layer 13 in the first embodiment, and will not be repeated here.

In this embodiment, the protective layer 34 can be made of titanium, titanium alloy, molybdenum, chromium, silicon, silicon oxide or titanium oxide. The remaining features and functions of the protective layer 34 are also the same as those of the protective layer 14 in the first embodiment, and will not be repeated here.

In the present invention, the flat panel display includes, but is not limited to, an organic electroluminescence (Organic Electroluminescence, OEL) display, an inorganic electroluminescence (Electroluminescence, EL) display, a light emitting diode (Light Emitting Diode, LED) display, a liquid crystal display (Liquid Crystal Display, LCD), plasma display (Plasma Display Panel, PDP), vacuum fluorescent display (Vacuum Fluorescent Display, VFD), field emission display (Field Emission Display, FED) and electrochromic display (Electro-chromicDisplay), etc. .

An electrode substrate of a flat panel display of the present invention has a protective layer for protecting the electrode layer. Compared with the known technology, the protective layer of the present invention can avoid the oxidation of the wiring layer due to the irradiation of ultraviolet light, thereby reducing the rise of the resistance value of the wiring layer, and at the same time, it can increase the adhesion with the photoresist layer. Moreover, the present invention can control the shape of the conductive line after etching (such as the angle between the side of the conductive line and the electrode layer is about 90 degrees), avoiding the electron migration caused by the deformed conductive line, and also avoiding the occurrence of short circuit , to further ensure the reliability of components. In addition, when the protective layer is made of titanium or titanium alloy, since a single etching solution can be used, only a single etching step is required to simultaneously etch the protective layer and the electrode layer. Furthermore, the present invention not only has a simple manufacturing process, but also does not increase the overall cost, which is very suitable for practical industrial applications.

The above descriptions are illustrative only, not restrictive. Any equivalent modification or change made without departing from the spirit and scope of the present invention shall be included in the description and scope of claims.

Claims (12)

1. the electrode base board of a flat-panel screens is characterized in that, comprises:

One substrate;

One electrode layer, it is formed on this substrate;

One conductor layer, it is formed on this electrode layer, and the material of this conductor layer is silver, silver alloy, aluminium, aluminium alloy, copper or copper alloy; Wherein, silver is weight percentage more than or equal to 99.5% silver, and aluminium is weight percentage more than or equal to 99.5% aluminium, and copper is weight percentage more than or equal to 99.5% copper; And

One protective layer, it is formed on this conductor layer, and the material of this protective layer be selected from titanium, titanium alloy, molybdenum, chromium, silicon, silica, titanium oxide one of them.

2. the electrode base board of flat-panel screens as claimed in claim 1, wherein this substrate is a flexible base, board or a rigid substrates.

3. the electrode base board of flat-panel screens as claimed in claim 1, wherein this substrate is a plastic base or a glass substrate.

4. the electrode base board of flat-panel screens as claimed in claim 1, wherein this electrode layer is the metal oxide electrode layer of conduction.

5. the electrode base board of flat-panel screens as claimed in claim 4, wherein this electrode layer is selected from a kind of formed electrode layer of tin indium oxide, aluminum zinc oxide and indium zinc oxide at least.

6. the electrode base board of flat-panel screens as claimed in claim 1, wherein the thickness of this conductor layer is 4000-6000 , and the thickness of this protective layer is less than 100 .

7. the electrode base board of a flat-panel screens is characterized in that, comprises:

One substrate:

One electrode layer, it is formed on this substrate;

One conductor wire pattern, it is formed on this electrode layer, this conductor wire pattern has at least one conductor wire, the side of this conductor wire and the angle of this electrode layer are 90 degree, and the material of this conductor wire pattern is silver, silver alloy, aluminium, aluminium alloy, copper or copper alloy, and wherein, silver is weight percentage more than or equal to 99.5% silver, and aluminium is weight percentage more than or equal to 99.5% aluminium, and copper is weight percentage more than or equal to 99.5% copper; And

One protective layer, it is formed on this conductor wire pattern, and the material of this protective layer be selected from titanium, titanium alloy, molybdenum, chromium, silicon, silica, titanium oxide one of them.

8. the electrode base board of flat-panel screens as claimed in claim 7, wherein this substrate is a flexible base, board or a rigid substrates.

9. the electrode base board of flat-panel screens as claimed in claim 7, wherein this substrate is a plastic base or a glass substrate.

10. the electrode base board of flat-panel screens as claimed in claim 7, wherein this electrode layer is the metal oxide electrode layer of conduction.

11. the electrode base board of flat-panel screens as claimed in claim 10, wherein this electrode layer is selected from a kind of formed electrode layer of tin indium oxide, aluminum zinc oxide and indium zinc oxide at least.

12. the electrode base board of flat-panel screens as claimed in claim 7, wherein the thickness of this conductor wire pattern is 4000-6000 , and the thickness of this protective layer is less than 100 .

Images