TWI542734B - Etching composition for copper and molibdenum alloy - Google Patents

Description

Etching solution composition of copper-molybdenum alloy film

The present invention relates to an etching liquid composition of a copper-molybdenum alloy film, particularly an etching liquid composition for a copper-molybdenum alloy film of a display electrode such as a TFT-LCD or an OLED.

A microcircuit such as a semiconductor device, a TFT-LCD, or an OLED is uniformly coated on a conductive metal film such as aluminum, aluminum alloy, copper, or copper alloy formed on a substrate, or an insulating film such as a hafnium oxide film or a tantalum nitride film. The photoresist is then imaged by light after being patterned, and the desired pattern photoresist is imaged, and the pattern is displayed on the metal film or the insulating film under the photoresist by dry etching or wet etching. After that, it is completed by stripping off a series of lithography processes such as unnecessary photoresist.

The copper alloy used for the gate of the large display and the data metal wiring has lower impedance and no environmental problems than the aluminum-chromium wiring in the prior art. Since copper has a low adhesion to a glass substrate and an insulating film and is easily diffused into a ruthenium oxide film, titanium, molybdenum or the like is generally used as the lower film metal.

Copper/molybdenum of a hydrogen peroxide substrate is disclosed in Korean Patent Publication No. 2003-0082375, Patent Publication No. 2004-0051502, Patent Publication No. 2006-0064881, and Patent Publication No. 2006-0099089, and the like. Alloy etching solution.

The copper/molybdenum alloy etchant contains fluoride for etching molybdenum alloys because When the fluoride is simultaneously etched with the copper/molybdenum alloy, the speed of etching the molybdenum alloy can be increased, and the residue of the molybdenum alloy can be removed. However, the above-mentioned fluoride can etch not only the molybdenum alloy but also the glass substrate which is the lower film of the copper/molybdenum alloy gate wiring and the lower film SiNx which is the source/drain wiring. When the etching of the lower film is increased, the etching of the stain in the post-treatment engineering and the rework engineering may result in an increase in the defective rate, and in the thinning process, the defective rate may also be increased due to the etching stain.

The high-tech circuits of mobile communication devices require that the display become thinner and thinner, and after manufacturing the TFT-LCD display array, a thinning process for thinning the glass substrate is required. In the etching process, if the etching of the glass substrate is increased, staining may occur due to uneven etching in the thinning process. In this case, etching is required to perform overall etching, and then repairing and reworking is performed. At this time, if the glass substrate is excessively etched, the etching stain remaining on the substrate may become a major cause of product failure.

Advanced technical literature Patent literature

(Patent Document 1) Korean Patent Publication No. 2003-0082375

(Patent Document 2) Korean Patent Publication No. 2004-0051502

(Patent Document 3) Korean Patent Publication No. 2006-0064881

(Patent Document 4) Korean Patent Publication No. 2006-0099089

The object of the present invention is to solve the above-mentioned deficiencies of the prior art, and to provide an etching rate of the lower film glass substrate and SiNx which can minimize the gate and source and drain when the copper/molybdenum alloy film is simultaneously etched, and to the maximum extent. To reduce the failure rate of defects caused by stains in post-treatment engineering and rework engineering and thinning engineering, thereby reducing the manufacturing cost of the copper-molybdenum alloy film etching solution group Compound.

The technical solution adopted by the present invention to solve the technical problem thereof is: an etching liquid composition of a copper-molybdenum alloy film, wherein: for the total weight of the composition, 5 to 40% by weight of hydrogen peroxide, 0.1 to 5% by weight Etch inhibitor, 0.1 to 5% by weight of chelating agent, 0.1 to 5% by weight of etching additive, 0.01 to 2% by weight of fluoride, 0.01 to 2% by weight of hydrogen peroxide stabilizer, 0.01 to 2% by weight of glass etching The inhibitor and 100% by weight of water, based on the total weight of the total composition.

The beneficial effects of the invention are: when simultaneously etching the copper/molybdenum alloy film, the etching speed of the lower film glass substrate and the SiNx as the gate and the source and drain can be minimized, and the post-treatment engineering and the minimization are minimized. The rate of failure due to stains in rework and thinning projects. In particular, the glass etching inhibitor can maintain the etching rate of the molybdenum alloy film in the fluoride-containing etching solution, and relatively slow down the etching rate of the glass substrate and the hafnium oxide film as the lower film.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a photograph (side view) of a scanning electron microscope of a profile of a sixth embodiment of the present invention when etching a copper/molybdenum alloy film using an etching solution; and Fig. 2 is a copper/molybdenum alloy used in an embodiment of the present invention. Photograph (planar) of the scanning electron microscope of the outline of the film etching; FIG. 3 is a scanning electron micrograph of the sixth embodiment of the present invention when the etching liquid is used to observe whether the glass is damaged; FIG. 4 is a comparative example 1 of the present invention. A scanning electron micrograph of the glass is observed when the etching solution is used.

The etching liquid composition of the present invention can simultaneously etch a copper/molybdenum alloy. Here's "copper / The molybdenum alloy film means a copper film and a molybdenum alloy film, and the molybdenum alloy is an alloy of molybdenum and various metals, preferably an alloy with titanium, niobium, chromium, niobium, nickel, indium or tin, more preferably an alloy with titanium.

The etching liquid composition of the copper-molybdenum alloy film of the present invention, comprising: 5 to 40% by weight of hydrogen peroxide, 0.1 to 5% by weight of an etching inhibitor, 0.1 to 5% by weight, based on the total weight of the composition a chelating agent, 0.1 to 5% by weight of an etching additive, 0.01 to 2% by weight of fluoride, 0.01 to 2% by weight of a hydrogen peroxide stabilizer, 0.01 to 2% by weight of a glass etching inhibitor, and 100 weights of the total weight of the total composition % water.

In the etching liquid composition of the present invention, hydrogen peroxide is a main acidifying agent of a copper-molybdenum alloy. For the total weight of the composition, it is preferably from 5 to 40% by weight of hydrogen peroxide, more preferably from 10 to 30% by weight of hydrogen peroxide. When the amount of hydrogen peroxide is less than 5% by weight, the acidification of the copper-molybdenum alloy is insufficient, and etching cannot be achieved. When the amount exceeds 40% by weight, the etching rate is too fast, and it is difficult to control the progress of the process.

The etching inhibitor contained in the etching liquid composition of the present invention can adjust the etching rate of the copper-molybdenum alloy to have an etching profile having an appropriate taper angle. For the total weight of the composition, it is preferably from 0.1 to 5% by weight of an etching inhibitor, more preferably from 0.5 to 3% by weight of an etching inhibitor. If it is less than 0.1% by weight, the performance of the adjustable taper angle is weakened, and if it exceeds 5% by weight, the etching rate is slowed, and the engineering efficiency is affected.

Preferably, the etching inhibitor is a 1- to 10-membered heterocyclic hydrocarbon compound containing at least one or more hetero atoms selected from the group consisting of oxygen, sulfur, and nitrogen, and not including a nitrogen atom and a sulfur atom. Specifically, it may be furan, thiophene, pyrrole, oxazole, imidazole, pyrazole, 1,2,4-triazole, tetrazole, oxonium, benzothiophene, anthracene, benzimidazole, benzopyrazole Azole, aminotetrazole, methyltetrazole, methylbenzotriazole, hydro-tolutriazole, hydroxymethylbenzotriazole a heterocyclic aromatic compound such as (hydroxye-tolutriazole); a heterocyclic aliphatic compound such as pyridazine, methylpyrazine, hydroxyethylpyrazine, pyrrolidine or alloxan; or one or more of the above may be used at the same time. Compound.

The etching liquid composition of the present invention includes a glass etching inhibitor in addition to the etching inhibitor, and can minimize the etching rate of the glass substrate as the lower film. Preferably, the glass etching inhibitor is a compound containing both a boron atom and a fluorine atom; more preferably, the glass etching inhibitor is borofluoric acid or a borofluoride, and more preferably selected from the group consisting of fluoroboric acid (HBF4) and fluorine. Sodium borate (NaBF4), potassium fluoroborate (KBF4), ammonium fluoroborate (NH4BF4), and mixtures thereof.

Preferably, the glass etching inhibitor is contained in an amount of from 0.01 to 2% by weight, more preferably from 0.05 to 1% by weight. If it is less than 0.01% by weight, the glass etching suppressing effect is small, and if it exceeds 2% by weight, the etching rate becomes slow and the engineering efficiency is affected.

In the etching liquid composition of the present invention, in order to adjust the etching rate, 0.1 to 5% by weight of an etching additive is further contained. The total weight of the composition is preferably from 0.1 to 5% by weight, more preferably from 0.5 to 3% by weight. If it is less than 0.1% by weight, the etching rate becomes slow, and etching cannot be achieved within a controllable engineering time. If it exceeds 5% by weight, the etching rate is too fast, and it is difficult to control the progress of the process.

Preferably, the etching additive is an organic acid, an inorganic acid or a salt thereof, and a compound containing nitrogen and sulfur or a mixture thereof.

The organic acid may be a water-soluble organic acid such as acetic acid, formic acid, butyric acid, citric acid, glycolic acid, oxalic acid, malonic acid, valeric acid, propionic acid, tartaric acid, gluconic acid, glycine or succinic acid, or may be used simultaneously. One or two or more of the above organic acids.

The inorganic acid is preferably nitric acid, sulfuric acid, phosphoric acid, hydrochloric acid, hypochlorous acid, or high manganese. Acid or a mixture thereof.

In the etching liquid composition of the present invention, the compound containing both a nitrogen atom and a sulfur atom is preferably a monocyclic or bicyclic compound of 1 to 10 members containing both a nitrogen atom and a sulfur atom, and more preferably a monocyclic ring of 5 to 10 members. Or a bicyclic compound. Specifically, it may be a thiol imidazoline, 2-thiol-1-methylimidazoline, 2-mercaptothiazole, 2-aminothiazole, decyltriazole, aminomercaptotriazole, decyltetrazolium, A Further, one or two or more of the above compounds may be used together, such as sulfhydryltetrazole, thiazole, phenylthiazole, 2-methylbenzothiazole, 2-aminobenzothiazole, and 2-mercaptobenzothiazole.

The additive containing both nitrogen and sulfur can control the etching solution inhibitor to excessively adsorb on the metal surface to slow the etching rate even when the etching process is repeated and the metal ion content in the etching liquid is increased. When the content of metal ions in the etching liquid is high, the etching rate can be maintained.

The chelating agent in the etching liquid composition of the present invention forms a chelate and deactivates copper and molybdenum alloy ions during etching to suppress decomposition reaction of hydrogen peroxide in the etching solution. If no chelating agent is added to the etching liquid composition of the present invention, the acidified metal ions cannot be deactivated during the etching process, which promotes the decomposition reaction of hydrogen peroxide in the etching liquid composition, which may result in Fever and explosion. The total weight of the composition is preferably from 0.1 to 5% by weight, more preferably from 0.5 to 3% by weight. When it is less than 0.1% by weight, the amount of inactivated metal ions is small, so that the effect of suppressing the decomposition reaction of hydrogen peroxide is weakened; if it exceeds 5% by weight, excessive chelation is formed to cause metal ions. The effect of inactivation is not good and affects engineering efficiency.

The chelating agent of the present invention is preferably a compound having both an amino group and a carboxylic acid group, In the body, it can be iminodiacetic acid, ammonia triacetic acid, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, aminotrimethylenephosphonic acid, 1-hydroxyethylidene-1,1-diphosphate, B. Diamine tetramethylphosphoric acid, diethylene triamine penta methylene phosphate, sarcosine, alanine, glutamic acid, aminobutyric acid and glycine.

When the fluoride in the etching liquid composition of the present invention is simultaneously etched in the copper-molybdenum alloy, the etching rate of the molybdenum alloy can be increased, the length of the tail can be reduced, and the molybdenum alloy residue generated during etching can be removed. If the tail of the molybdenum alloy is increased, the brightness will be lowered, and if the residue remains on the substrate and the lower film, electrical short-circuit, poor wiring, and reduced brightness will be caused, so the residue must be removed. The fluoride is preferably present in an amount of from 0.01 to 2% by weight, more preferably from 0.1 to 1% by weight, based on the total weight of the composition. When it is less than 0.01% by weight, the residue of the molybdenum alloy cannot be effectively removed, and if it exceeds 2% by weight, the lower film is etched.

The fluoride of the present invention is a compound which decomposes F- or HF2- ions, and may be hydrazine, sodium fluoride, potassium fluoride, aluminum fluoride, borofluoric acid, ammonium fluoride, ammonium hydrogen fluoride, sodium hydrogen fluoride or potassium hydrogen fluoride. Further, one or two or more kinds of the above-mentioned fluorides may be used together with ammonium fluoroborate or the like. The hydrogen peroxide stabilizer in the etching liquid composition of the present invention can be repeatedly subjected to an etching process, and when the metal ion content in the etching liquid is high, the decomposition reaction of hydrogen peroxide is controlled. The hydrogen peroxide stabilizer is selected from the group consisting of phosphates, glycols, and amines, and is preferably contained in an amount of from 0.01 to 2% by weight.

The copper/molybdenum alloy etching liquid composition of the present invention may further contain any one of additives known in the art in order to improve the etching performance. The additive may be a surfactant for improving etching performance. The kind of the surfactant is not limited as long as it is used in the art.

The water used in the etching liquid composition of the present invention is not particularly limited, and preferably In order to use deionized water, it is more preferable to use deionized water having a specific resistance value of 18 MΩ/cm or more after removing ions using water.

By using the etching liquid composition of the present invention, a copper/molybdenum alloy film for an electrode such as a TFT-LCD display or an OLED can be etched, the etching of the lower film can be minimized, and the post-treatment engineering and glass can be minimized. The rate of failure in substrate thinning engineering or rework engineering.

The present invention is described in detail with reference to the embodiments of the present invention. The embodiments are merely illustrative of the invention, and the invention is not limited by the embodiments.

<Examples 1 to 6 and Comparative Example 1>

The components of the compositions of Examples 1 to 6 and Comparative Example 1 were prepared by mixing the components in the amounts of the components described in the following Table 1.

ATZ: 5-aminotetrazole, IDA: iminodiacetic acid, BTZ: benzothiazole, PEG: polyethylene glycol.

<etching efficiency test>

In order to evaluate the effect of the etching liquid of the present invention, a copper-molybdenum alloy film having a thickness of 3100 Å was deposited on a glass substrate, and then subjected to photolithography engineering to form a pattern to prepare a test piece.

Further, in order to evaluate the etching of the glass substrate, a pattern was formed by performing photolithography on the glass substrate to prepare a test piece.

The etching liquid compositions of Examples 1 to 6 and the etching liquid composition of Comparative Example 1 were carried out on a sprayable device (Mini-etcher ME-001). After the etching, the etching characteristics of the copper-molybdenum alloy film and the etching of the glass substrate were observed by a scanning electron microscope (manufactured by Hitachi, Ltd., S-4800). In order to confirm the etching characteristics, etching was performed for 90 seconds; in order to confirm the etching of the glass substrate, etching was performed for 200 seconds.

The experimental results are shown in [Table 2].

[Table 2]

As shown in Table 2, the compositions of Examples 1 to 6 of the present invention have excellent etching deviation, etching cone angle, tail length, etc., and the etching of the glass substrate is about 1/33 to 1/3. , got a considerable degree of inhibition.

1 and 2 are side and plan photographs of a scanning electron microscope of a profile of a sixth embodiment of the present invention when etching a copper/molybdenum alloy film using an etching solution.

3 and 4 are scanning electron micrographs of the invention of Example 6 and Comparative Example 1 when the etching liquid was used to observe whether the glass was damaged. It can be seen that the etching of the glass substrate of Comparative Example 1 is more serious.

In summary, when etching a copper/molybdenum alloy film for an electrode such as a TFT-LCD display or an OLED using the etching liquid composition of the present invention, etching of the lower film can be minimized, and the degree of etching can be minimized. Reduce the failure rate of post-treatment engineering and glass substrate thinning engineering or rework engineering.

Claims (7)

An etching solution composition of a copper-molybdenum alloy film, comprising: 5 to 40% by weight of hydrogen peroxide, 0.1 to 5% by weight of an etching inhibitor, and 0.1 to 5% by weight of a chelating agent for the total weight of the composition 0.1 to 5% by weight of an etching additive, 0.01 to 2% by weight of fluoride, 0.01 to 2% by weight of a hydrogen peroxide stabilizer, 0.01 to 2% by weight of a glass etching inhibitor, and 100% by weight of the total weight of the total composition Water; wherein the glass etching inhibitor is a compound containing both a boron atom and a fluorine atom; the etching additive is a compound containing both a nitrogen atom and a sulfur atom; and the hydrogen peroxide stabilizer is selected from the group consisting of glycols and amines Compound. The etching liquid composition of the copper-molybdenum alloy film according to claim 1, wherein the glass etching inhibitor is fluoroboric acid or fluoroborate. The etching solution composition of the copper-molybdenum alloy film according to claim 2, wherein the glass etching inhibitor is selected from the group consisting of fluoroboric acid (HBF4), sodium fluoroborate (NaBF4), and potassium fluoroborate (KBF4). Ammonium fluoroborate (NH4BF4) and mixtures thereof. The etching liquid composition of the copper-molybdenum alloy film according to the first aspect of the invention, wherein the etching inhibitor is a 1 to 10 membered heterocyclic ring containing at least one or more hetero atoms selected from the group consisting of oxygen, sulfur and nitrogen. Hydrocarbons. The etching liquid composition of the copper-molybdenum alloy film according to the first aspect of the invention, wherein the chelating agent is a compound having both an amino group and a carboxylic acid group. The etchant composition of the copper-molybdenum alloy film according to the first aspect of the invention, wherein the fluoride is a compound which decomposes F- or HF2- ions. The etching liquid composition of the copper-molybdenum alloy film according to claim 1, which further comprises a surfactant.