KR102423605B1 - Etchant composition and manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

The present invention relates to an etchant composition and a method of manufacturing an array substrate for a liquid crystal display. When the copper-based metal film is etched with the etchant composition of the present invention, the etching profile is excellent and the number of treatment sheets is high.

Description

Etchant composition and method of manufacturing an array substrate for a liquid crystal display

The present invention relates to an etchant composition and a method of manufacturing an array substrate for a liquid crystal display.

A representative electronic circuit for driving semiconductor devices and flat panel display devices is a thin film transistor (TFT). A TFT manufacturing process usually consists of forming a metal film as a material for a gate and data wiring on a substrate, forming a photoresist in a selective region of the metal film, and then etching the metal film using the photoresist as a mask.

Gate wiring and data wiring use copper with good electrical conductivity and low resistance, but in the case of copper, there are difficulties in the process of applying and patterning a photoresist. A metal film is applied. Among copper-based metal films, a titanium/copper double film is generally widely used. However, when the titanium/copper double layer is simultaneously etched, there are disadvantages in that the etch profile is poor, the subsequent process is difficult, and the copper eluted as the etching proceeds and the number of treatment sheets is low accordingly. Accordingly, a copper-based metal film etchant composition is being actively studied, and as an example, in Korean Patent Application Laid-Open No. 2015-0059800, a liquid composition containing a maleate ion source, a copper ion source and a fluoride ion source and having a pH value of 0 to 7 is provided. have. However, the liquid composition has a disadvantage in that the etching profile is not good and the ability of the number of sheets to be processed is lowered.

Therefore, when etching a copper-based metal film such as a titanium/copper double film, research on an etchant composition having an excellent etching profile and a high treatment number is continuously required.

Republic of Korea Patent Publication No. 2015-0059800

Accordingly, an object of the present invention is to provide an etchant composition for a copper-based metal film having an excellent etch profile and a high number of treatment sheets.

In order to solve the above problems, the present invention is based on the total weight of the composition,

0.5 to 10 wt% of a copper compound;

0.01 to 2 wt% of a fluorine compound;

1 to 10% by weight of at least one inorganic acid selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid and perchloric acid;

0.1 to 10 weight of at least one chlorine compound selected from the group consisting of hydrochloric acid, sodium chloride, potassium chloride, ammonium chloride, methanesulfonyl chloride, ethanesulfonyl chloride, chlorobenzenesulfonyl chloride, benzenesulfonyl chloride and chloroethanesulfonyl chloride %;

Acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, succinic acid, malic acid , 1 to 10% by weight of at least one organic acid selected from the group consisting of tartaric acid, isocitric acid, propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid or a salt thereof;

At least one non-metallic inorganic salt selected from the group consisting of ammonium sulfate, sodium sulfate, potassium sulfate, calcium sulfate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, calcium hydrogen sulfate, ammonium nitrate, sodium nitrate, potassium nitrate and calcium nitrate 0.1 to 10% by weight;

0.01 to 5 wt% of a cyclic amine compound;

0.5 to 10% by weight of a chelating agent; and

including the remaining water,

The chelating agent provides a copper-based metal film etchant composition, characterized in that at least one selected from the group consisting of malonic acid, succinic acid, and glutaric acid, or a salt thereof .

In one embodiment, the copper-based metal layer may be a double layer of titanium or a titanium alloy and a copper or copper alloy.

In addition, the present invention comprises the steps of: a) forming a gate wiring on a substrate;

b) forming a gate insulating layer on the substrate including the gate wiring;

c) forming a semiconductor semiconductor layer on the gate insulating layer;

d) forming source and drain electrodes on the semiconductor layer; and

e) a method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the drain electrode,

Step a) or d) comprises forming a copper-based metal film on a substrate or semiconductor layer, and etching the copper-based metal film with an etchant composition to form a gate wiring or source and drain electrodes,

The etchant composition is 0.5 to 10% by weight of a copper compound based on the total weight of the composition; 0.01 to 2 wt% of a fluorine compound; 1 to 10% by weight of at least one inorganic acid selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid and perchloric acid; 0.1 to 10 weight of at least one chlorine compound selected from the group consisting of hydrochloric acid, sodium chloride, potassium chloride, ammonium chloride, methanesulfonyl chloride, ethanesulfonyl chloride, chlorobenzenesulfonyl chloride, benzenesulfonyl chloride and chloroethanesulfonyl chloride %; Acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, succinic acid, malic acid , 1 to 10% by weight of at least one organic acid selected from the group consisting of tartaric acid, isocitric acid, propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid or a salt thereof; At least one non-metallic inorganic salt selected from the group consisting of ammonium sulfate, sodium sulfate, potassium sulfate, calcium sulfate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, calcium hydrogen sulfate, ammonium nitrate, sodium nitrate, potassium nitrate and calcium nitrate 0.1 to 10% by weight; 0.01 to 5 wt% of a cyclic amine compound; 0.5 to 10% by weight of a chelating agent, which is at least one selected from the group consisting of malonic acid, succinic acid, and glutaric acid, or a salt thereof; and a residual amount of water.

In one embodiment, the array substrate for a liquid crystal display may be a thin film transistor (TFT) array substrate.

In another embodiment, the copper-based metal layer may be a double layer of titanium or a titanium alloy and a copper or copper alloy.

In addition, the present invention provides an array substrate for a liquid crystal display manufactured by the above manufacturing method.

When the copper-based metal film is etched with the etchant composition of the present invention, the etching profile is excellent and the number of treatment sheets is high.

1 shows the profile of the titanium/copper double layer etching with the etching solution composition of Example 1 and Comparative Example 11.

The present invention relates to an etchant composition and a method of manufacturing an array substrate for a liquid crystal display.

The etchant composition of the present invention contains at least one selected from the group consisting of malonic acid, succinic acid, and glutaric acid or a salt thereof in a certain amount as a chelating agent. When etching a metal film, it is characterized by an excellent etch profile and a high number of treatment sheets.

Hereinafter, the present invention will be described in detail.

etchant composition

In the present invention, the copper compound serves as an oxidizing agent and maintains CD Skew without fluctuation when the etchant etches the metal film, and is included in an amount of 0.5 to 10% by weight based on the total weight of the etchant. desirable. If the content is less than 0.5 wt%, copper or a metal film containing copper cannot be etched or the etching rate is very slow and the initial etching is not uniform. If it exceeds 10% by weight, there is no effect of increasing the number of treated sheets. The copper compound is preferably at least one selected from the group consisting of copper sulfate, copper chloride, and copper nitrate.

The fluorine compound is a main component for etching titanium or a metal film containing titanium, and serves to remove residues that may be generated during etching. The fluorine compound is preferably included in an amount of 0.01 to 2 wt% based on the total weight of the etchant. If the content of the fluorine compound is less than 0.01% by weight, the etching rate of titanium or a metal film containing titanium may be lowered and residues may be generated. It may cause damage to the insulating film including silicon formed together. The fluorine compound may be a compound in which fluorine ions or polyatomic fluorine ions are dissociated in a solution, and ammonium fluoride, sodium fluoride, potassium fluoride, ammonium bifluoride ), it is preferable to use at least one selected from the group consisting of sodium bifluoride and potassium bifluoride.

At least one inorganic acid selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid and perchloric acid is an auxiliary oxidizing agent for etching a metal film containing copper or copper and a metal film containing titanium or titanium, based on the total weight of the etchant. It is preferably included in 10% by weight. When the content of the inorganic acid is less than 1% by weight, the etching rate of the metal film containing copper or copper and the metal film containing titanium or titanium is lowered, so that an etch profile defect and residue may occur, and 10% by weight If it exceeds, over-etching and photoresist cracks may occur, and wiring may be short-circuited by chemical penetration.

At least one chlorine compound selected from the group consisting of hydrochloric acid, sodium chloride, potassium chloride, ammonium chloride, methanesulfonyl chloride, ethanesulfonyl chloride, chlorobenzenesulfonyl chloride, benzenesulfonyl chloride and chloroethanesulfonyl chloride is an auxiliary agent for the metal film. It acts as an oxidizer and controls the etching rate and angle of the metal film, and has the advantage of preventing wiring open. The chlorine compound is preferably included in an amount of 0.1 to 10% by weight based on the total weight of the composition. When the content of the chlorine compound is less than 0.1 wt%, the etching rate of copper is lowered and the etching time in the process may be prolonged, which may cause a problem in productivity. In addition, when it contains more than 10 wt%, it is impossible to control the etching rate of copper, so over-etching may occur.

Acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, succinic acid, malic acid , tartaric acid, isocitric acid, propenoic acid, iminodiacetic acid and at least one organic acid selected from the group consisting of ethylenediaminetetraacetic acid or a salt thereof increases the solubility of copper ions and the chelating agent during precipitation and lowers the pH, It plays a role in controlling the etching rate. The organic acid or its salt is preferably included in an amount of 1 to 10% by weight based on the total weight of the etchant. When the content of the organic acid or organic acid salt is less than 1% by weight, there is no effect of increasing the number of treatment sheets, and when it exceeds 10% by weight, over-etching may occur and the wiring may be short-circuited.

At least one non-metallic inorganic salt selected from the group consisting of ammonium sulfate, sodium sulfate, potassium sulfate, calcium sulfate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, calcium hydrogen sulfate, ammonium nitrate, sodium nitrate, potassium nitrate and calcium nitrate Silver acts as an auxiliary etch control agent for the metal film, and has the effect of improving the poor etch profile, which is a disadvantage of the etchant containing chlorine compounds. The non-metallic inorganic salt is preferably included in an amount of 0.1 to 10% by weight based on the total weight of the composition. If it is less than 0.1% by weight, it does not have the effect of the auxiliary etch control agent and the etch profile improvement effect, and if it exceeds 10% by weight, over-etching may occur.

The cyclic amine compound is an etching control agent for controlling copper or copper-containing batch etching and angle. The cyclic amine compound is preferably included in an amount of 0.01 to 5% by weight based on the total weight of the composition. If it is less than 0.01 wt%, uniform etching of the metal film is not performed, and if it exceeds 5 wt%, the etching rate may be lowered. The cyclic amine compound is 5-aminotetrazole, triazole, phenyltetrazole, imidazole, indole, purine, pyrazole, pyridine, pyridine. It is preferable to use at least one selected from the group consisting of midine, pyrrole, pyrrolidine, pyrroline, and 5-methyltetrazole.

Water means deionized water and is used for semiconductor processing, preferably water of 18㏁/cm or more. With respect to the total content of the etchant, the remaining amount of water is included so that the total weight of the etchant is 100% by weight.

The chelating agent, which is at least one selected from the group consisting of malonic acid, succinic acid, and glutaric acid, or a salt thereof, serves as a main component for increasing the number of treatments, and the total weight of the composition It is preferably included in an amount of 0.5 to 10% by weight with respect to the . When it is less than 0.5 wt%, there is no effect of increasing the number of treatments, and when it exceeds 10 wt%, the etching rate of the metal film increases and over-etching may occur.

In the present invention, the etchant composition may further include a metal ion sequestrant and a corrosion inhibitor.

Manufacturing method of array substrate for liquid crystal display

A method for manufacturing an array substrate for a liquid crystal display of the present invention,

a) forming a gate wiring on the substrate;

b) forming a gate insulating layer on the substrate including the gate wiring;

c) forming a semiconductor semiconductor layer on the gate insulating layer;

d) forming source and drain electrodes on the semiconductor layer; and

e) a method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the drain electrode,

Step a) or d) comprises forming a copper-based metal film on a substrate or semiconductor layer, and etching the copper-based metal film with the etchant composition of the present invention to form a gate wiring or source and drain electrodes It may be a method of manufacturing a liquid crystal display array substrate characterized in that.

The array substrate for the liquid crystal display may be a thin film transistor (TFT) array substrate, but is not limited thereto, and may be used in the manufacture of other electronic devices including metal wires made of copper-based metal layers, such as the manufacture of a memory semiconductor panel.

Hereinafter, the present invention will be described in more detail using Examples, Comparative Examples and Experimental Examples. However, the following Examples, Comparative Examples and Experimental Examples are intended to illustrate the present invention, and the present invention is not limited by the following Examples, Comparative Examples and Experimental Examples and may be variously modified and changed.

Example 1-17 and comparative example 1 to 15. etchant Preparation of the composition

An etchant composition was prepared with the composition and content (unit: wt%) shown in Table 1 below.

division (A) (B) (C) (D) (E) (F) (G) (H) (I) (J) (K) water Example 1 3 0.5 5 6 2 3 One 2 - - - remaining amount Example 2 0.5 0.5 5 6 2 3 One 2 - - - remaining amount Example 3 10 0.5 5 6 2 3 One 2 - - - remaining amount Example 4 3 0.5 One 6 2 3 One 2 - - - remaining amount Example 5 3 0.5 10 6 2 3 One 2 - - - remaining amount Example 6 3 0.5 5 One 2 3 One 2 - - - remaining amount Example 7 3 0.5 5 10 2 3 One 2 - - - remaining amount Example 8 3 0.5 5 6 0.3 3 One 2 - - - remaining amount Example 9 3 0.5 5 6 10 3 One 2 - - - remaining amount Example 10 3 0.5 5 6 2 One One 2 - - - remaining amount Example 11 3 0.5 5 6 2 10 One 2 - - - remaining amount Example 12 3 0.5 5 6 2 3 0.05 2 - - - remaining amount Example 13 3 0.5 5 6 2 3 5 2 - - - remaining amount Example 14 3 0.5 5 6 2 3 One One - - - remaining amount Example 15 3 0.5 5 6 2 3 One 10 - - - remaining amount Example 16 3 0.5 5 6 2 3 One - 2 - - remaining amount Example 17 3 0.5 5 6 2 3 One - - 2 - remaining amount Comparative Example 1 3 0.5 5 6 2 3 One - - - - remaining amount Comparative Example 2 3 0.5 5 6 2 3 One - - - 4 remaining amount Comparative Example 3 - 0.5 5 6 2 3 One 2 - - - remaining amount Comparative Example 4 13 0.5 5 6 2 3 One 2 - - - remaining amount Comparative Example 5 3 0.5 0.5 6 2 3 One 2 - - - remaining amount Comparative Example 6 3 0.5 13 6 2 3 One 2 - - - remaining amount Comparative Example 7 3 0.5 5 - 2 3 One 2 - - - remaining amount Comparative Example 8 3 0.5 5 13 2 3 One 2 - - - remaining amount Comparative Example 9 3 0.5 5 6 0 3 One 2 - - - remaining amount Comparative Example 10 3 0.5 5 6 13 3 One 2 - - - remaining amount Comparative Example 11 3 0.5 5 6 2 0 One 2 - - - remaining amount Comparative Example 12 3 0.5 5 6 2 13 One 2 - - - remaining amount Comparative Example 13 3 0.5 5 6 2 3 0 2 - - - remaining amount Comparative Example 14 3 0.5 5 6 2 3 7 2 - - - remaining amount Comparative Example 15 3 0.5 5 6 2 3 One 13 - - - remaining amount

(A): Cu(II)SO ₄

(B): Ammonium fluoride

(C): nitric acid

(D): citric acid

(E): Ammonium Chloride

(F): Ammonium sulfate

(G): 5-methyltetrazole

(H): malonic acid

(I): succinic acid

(J): glutaric acid

(K): adipic acid

Experimental example . etching characterization

The etching process was performed using the etchant compositions of Examples 1 to 17 and Comparative Examples 1 to 15, respectively. Experimental equipment (model name: ETCHER (TFT), SEMES Co., Ltd.) of the spray-type etching method was used, and the temperature of the etchant composition during the etching process was about 30°C. The etching time may vary depending on the etching temperature, but in the LCD etching process, it was usually performed for about 30 to 80 seconds. The profile of the titanium/copper double film etched in the etching process was observed for cross-section using SEM (manufactured by Hitachi, model name S-4700), and the results are shown in Table 2 and FIG. 1 below.

division number of transactions
(ppm) Example 1 6000 Example 2 5500 Example 3 6500 Example 4 5000 Example 5 7000 Example 6 5000 Example 7 7000 Example 8 5000 Example 9 7000 Example 10 5500 Example 11 6500 Example 12 6000 Example 13 6500 Example 14 5000 Example 15 10000 Example 16 6000 Example 17 5500 Comparative Example 1 4000 Comparative Example 2 4000 Comparative Example 3 Un-Etch Comparative Example 4 5500 Comparative Example 5 Decreased etching rate Comparative Example 6 over-etched Comparative Example 7 3000 Comparative Example 8 over-etched Comparative Example 9 Decreased etching rate Comparative Example 10 over-etched Comparative Example 11 Decreased etching rate
Bad etch profile Comparative Example 12 over-etched Comparative Example 13 Non-uniform etching Comparative Example 14 Decreased etching rate Comparative Example 15 over-etched

Un-Etch: Cu is not etched in the non-patterned part, so the pattern is not formed

Defective etching profile: In SEM measurement, it means that the straightness of the Cu wiring in the pattern part and the inclined surface are defective.

As shown in Table 2, Examples 1 to 17 were superior to Comparative Examples 1 to 15 in terms of the number of treatment sheets and etching profile. In particular, as shown in FIG. 1 , Example 1 exhibited an excellent etching profile compared to Comparative Example 11 in which an inorganic salt (ammonium sulfate) was not added.

Claims (6)

with respect to the total weight of the composition,
0.5 to 10 wt% of a copper compound;
0.01 to 2 wt% of a fluorine compound;
1 to 10% by weight of at least one inorganic acid selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid and perchloric acid;
0.1 to 10 weight of at least one chlorine compound selected from the group consisting of hydrochloric acid, sodium chloride, potassium chloride, ammonium chloride, methanesulfonyl chloride, ethanesulfonyl chloride, chlorobenzenesulfonyl chloride, benzenesulfonyl chloride and chloroethanesulfonyl chloride %;
Acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, isocitric acid, 1 to 10% by weight of at least one organic acid selected from the group consisting of propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid or a salt thereof;
At least one inorganic salt selected from the group consisting of ammonium sulfate, sodium sulfate, potassium sulfate, calcium sulfate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, calcium hydrogen sulfate, ammonium nitrate, sodium nitrate, potassium nitrate and calcium nitrate 0.1 to 10% by weight;
0.01 to 5 wt% of a cyclic amine compound;
0.5 to 10% by weight of a chelating agent; and
including the remaining water,
A copper-based metal film etchant composition that does not contain a persulfate,
The chelating agent is one or more selected from the group consisting of malonic acid, succinic acid, and glutaric acid, or a salt thereof, a copper-based metal film etchant composition. The method according to claim 1,
The copper-based metal film is titanium or a titanium alloy and a copper or copper alloy double film, the copper-based metal film etchant composition. a) forming a gate wiring on the substrate;
b) forming a gate insulating layer on the substrate including the gate wiring;
c) forming a semiconductor semiconductor layer on the gate insulating layer;
d) forming source and drain electrodes on the semiconductor layer; and
e) a method of manufacturing an array substrate for a liquid crystal display comprising the step of forming a pixel electrode connected to the drain electrode,
Step a) or d) comprises forming a copper-based metal film on a substrate or semiconductor layer, and etching the copper-based metal film with an etchant composition to form a gate wiring or source and drain electrodes,
The etchant composition is 0.5 to 10% by weight of a copper compound based on the total weight of the composition; 0.01 to 2 wt% of a fluorine compound; 1 to 10% by weight of at least one inorganic acid selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid and perchloric acid; 0.1 to 10% by weight of at least one chlorine compound selected from the group consisting of hydrochloric acid, sodium chloride, potassium chloride, ammonium chloride, methanesulfonyl chloride, ethanesulfonyl chloride, chlorobenzenesulfonyl chloride, benzenesulfonyl chloride and chloroethanesulfonyl chloride; Acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, isocitric acid, 1 to 10% by weight of at least one organic acid selected from the group consisting of propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid or a salt thereof; At least one inorganic salt selected from the group consisting of ammonium sulfate, sodium sulfate, potassium sulfate, calcium sulfate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, calcium hydrogen sulfate, ammonium nitrate, sodium nitrate, potassium nitrate and calcium nitrate 0.1 to 10% by weight; 0.01 to 5 wt% of a cyclic amine compound; 0.5 to 10% by weight of a chelating agent, which is at least one selected from the group consisting of malonic acid, succinic acid, and glutaric acid, or a salt thereof; and the remaining amount of water, and does not contain persulfate,
A method of manufacturing an array substrate for a liquid crystal display. 4. The method according to claim 3,
The liquid crystal display array substrate is a thin film transistor (TFT) array substrate, characterized in that the liquid crystal display array substrate manufacturing method. 4. The method of claim 3,
The copper-based metal layer is a method of manufacturing an array substrate for a liquid crystal display, characterized in that the titanium or titanium alloy and copper or copper alloy double layer. An array substrate for a liquid crystal display manufactured by the manufacturing method of claim 3.

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