KR101733804B1 - Etching solution composition for formation of metal line - Google Patents

Abstract

The present invention relates to an etchant composition for metal wiring formation. Since the etchant composition can wet etch multiple layers of a single layer or two or more layers formed of at least one metal selected from the group consisting of titanium, titanium alloys, aluminum and aluminum alloys, and the number of etch processes is large, Thereby significantly improving productivity. In addition, the etching rate is fast, there is no damage to the underlying film and equipment, homogeneous etching between pattern / non-pattern is possible, and excellent etching characteristics are provided, and expensive equipment configuration is not required, Lt; / RTI >

Titanium, aluminum, multi-layer, wet, etchant

Description

TECHNICAL FIELD [0001] The present invention relates to an etchant composition for forming a metal wiring,

The present invention relates to a method of manufacturing a semiconductor device, which comprises a single film formed of one or more metals selected from the group consisting of titanium, titanium alloys, aluminum and aluminum alloys, which are used for gate and source / To an etchant composition capable of wet etching.

The process of forming a metal wiring on a substrate in a flat panel display device is usually composed of a metal film forming process by sputtering, a photoresist coating process, a photoresist forming process in an optional region by exposure and development, and a step by an etching process And a cleaning process before and after the individual unit process. This etching process refers to a process of leaving a metal film on a selective region by using a photoresist mask, and dry etching using plasma or wet etching using an etching solution is usually used.

As the conductive film of the metal film included in the flat panel display, Al having a low resistance is used. In the subsequent process, the aluminum layer causes a shorting phenomenon with another conductive layer by the Hillock, Is formed. Therefore, Mo, Ti, Cr and an alloy mainly composed of them are used for the upper or lower part of the aluminum as the buffer layer. In recent years, Ti having corrosion resistance, firmness and high strength has been spotlighted.

Although the electrode used as the buffer layer of the Ti layer is etched using a halogen gas by a dry etching process in the past, it has an anisotropic profile and an excellent etching control ability compared with the wet etching process, There is a problem that the equipment is required, the configuration of the large-sized surface is difficult, the productivity is deteriorated because the etching speed is slow.

Accordingly, methods of wet etching the Ti buffer layer as described above have been developed. For example, Korean Patent Application Nos. 10-1999-0005010 and 10-1999-0043017 disclose the use of HF as a main component of an etchant composition for wet etching a Ti layer.

However, when HF is used as the main component for wet etching, there are many restrictions on the process conditions due to the damage of the lower film and equipment, and this restriction acts as a cause of lowering the productivity.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the conventional art,

A single film or a multilayer film composed of at least one metal selected from the group consisting of titanium, titanium alloy, aluminum and aluminum alloy can be wet-etched all at once, and the number of etching processes can be increased to greatly improve the productivity of the etching process ; High etch rate, no damage to underlying films and equipment, uniform etch between pattern / non-pattern is possible, thus providing excellent etch characteristics; It is an object of the present invention to provide an economical etchant composition which is advantageous in large-scale and does not require expensive equipment construction.

According to the present invention,

Wherein the composition comprises 1 to 30 wt% of H ₂ O ₂ , 0.1 to 2 wt% of a fluorine compound, 1 to 10 wt% of a compound containing both an amino group and a carboxyl group simultaneously, 0.1 to 5 wt% An etchant composition of a single film or a bilayer or more multilayer film formed of at least one metal selected from the group consisting of titanium, titanium alloy, aluminum and aluminum alloy containing 0.01 to 5% by weight of a cyclic amine compound and residual water, to provide.

The etchant composition of the present invention can wet etch multiple layers of a single layer or a double layer or more formed of at least one metal selected from the group consisting of titanium, titanium alloy, aluminum and aluminum alloy, Thereby significantly improving productivity. In addition, the etching rate is fast, there is no damage to the underlying film and equipment, homogeneous etching between pattern / non-pattern is possible, and excellent etching characteristics are provided, and expensive equipment configuration is not required, Lt; / RTI >

The present invention relates to a composition comprising 1 to 30% by weight of H ₂ O ₂ , 0.1 to 2% by weight of a fluorine compound, 1 to 10% by weight of a compound simultaneously containing an amino group and a carboxyl group, 0.1 to 5% A single membrane formed of at least one metal selected from the group consisting of nitrate compounds, 0.01 to 5 wt% of cyclic amine compounds and titanium, titanium alloys, aluminum and aluminum alloys containing the remaining amount of water, To an etchant composition.

The etchant composition of the present invention is an etchant for collectively etching multiple layers of a single layer or a double layer or more formed of at least one metal selected from the group consisting of titanium, titanium alloys, aluminum and aluminum alloys, Or a multi-metal film including a double-layered film of titanium or a titanium alloy film laminated on the upper or lower portion of an aluminum alloy film, and also a triple-layered film in which a titanium or titanium alloy film and an aluminum or aluminum alloy film are alternately laminated.

The etchant composition of the present invention can be preferably used particularly for a triple layer in which the upper layer is a titanium or titanium alloy film, the intermediate layer is an aluminum or aluminum alloy film, and the lower layer is a titanium or titanium alloy film.

The titanium or titanium alloy film is a concept that includes a Ti film or a metal film composed of an alloy mainly composed of Ti and other metals depending on the characteristics of the film. An aluminum or aluminum alloy film is a film containing Al And a metal film made of an alloy as a main component and using another metal.

In the present invention, H ₂ O ₂ serves to oxidize the surfaces of the Ti and Al films and is preferably contained in an amount of 1 to 30% by weight based on the total weight of the composition. When H ₂ O ₂ is contained in an amount of less than 1% by weight A difference in the etching rate between the Ti and Al layers and an etching rate difference between the pattern and the non-pattern become large, causing a process problem. When the amount exceeds 30% by weight, pattern loss due to overgrowth of the Ti and Al films occurs, This function may be lost.

In the present invention, the fluorine compound serves to etch the surfaces of the oxidized Ti and Al films, and preferably contains 0.1 to 2% by weight based on the total weight of the composition. If it is contained in an amount less than 0.1% by weight, residues are generated due to the low etching rate of the Ti and Al films located at the upper and lower portions, or unevenness occurs in the substrate due to the uneven etching, and when it exceeds 2% by weight, Damage to the film may occur, and control of the process speed is also difficult.

The fluorine-containing compound means a compound capable of dissociating fluorine ions or polyatomic fluorine ions. Examples of the fluorine-containing compounds include ammonium fluoride, sodium fluoride, potassium fluoride, sodium bisulfite, potassium bisulfide, Hydrogen fluoride, etc. These may be used singly or in combination of two or more.

The compound having an amino group and a carboxyl group in the present invention serves as a modifier for providing Ti removal and etching uniformity improvement effects on the Ti film.

The compound is preferably contained in an amount of 1 to 10% by weight based on the total weight of the composition. If it is contained in an amount of less than 1% by weight, a tip of the Ti film may be generated to cause a problem in a subsequent step, and if it exceeds 10% by weight, an overexcitation phenomenon of the Ti film may occur.

Examples of the compound having an amino group and a carboxyl group include alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid, and sarcosine compounds. These compounds may be used singly or in combination of two or more Can be used together.

Specific examples include alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid, and sarcosine. .

In the present invention, the nitrate compound serves to improve the linearity of the wiring made of Ti and Al films at the time of etching, and is preferably contained in an amount of 0.1 to 5 wt% based on the total weight of the composition. If the nitrate compound is contained in an amount of less than 0.1% by weight, the etching uniformity is lowered and the wiring shape is unevenly formed, thereby causing staining problems in the substrate. On the other hand, if it exceeds 5% by weight, overeating phenomenon occurs due to an increase in the etching rate of Ti and Al films, and unevenness due to lowering of etching uniformity occurs.

In the present invention, the nitrate compound means an organic compound containing nitrate ions such as ammonium nitrate, sodium nitrate and potassium nitrate, They may be used alone or in combination of two or more.

In the present invention, the cyclic amine compound increases the Ti and Al metal ions in the etchant during etching. The increase of the metal ion causes the deterioration of the etching property by causing the etching rate to decrease due to the composition change in the chemical solution. The cyclic amine compound reacts with metal ions to form a stable form, thereby increasing the number of substrates processed. The cyclic amine compound is preferably contained in an amount of 0.01 to 5% by weight based on the total weight of the composition. If the amount of the cyclic compound is less than 0.01% by weight, the effect of stabilizing the metal ion is insignificant. If the amount of the cyclic compound is more than 5% by weight, the solubility of the cyclic compound is low.

Examples of the cyclic amine compound include pyrrolidine, pyrrole, pyrrole, indole, pyrazole, imidazole, pyrimidine, purine, pyridine, benzotriazole and derivatives thereof. More than one species can be used together.

 The water used in the present invention means deionized water and is used for semiconductor processing, preferably water of 18 M / cm or more.

In addition to the above-mentioned components, conventional additives may further be added to the etchant composition of the present invention. Examples of such additives include etch control agents, surfactants, metal ion sequestrants, corrosion inhibitors, and pH adjusting agents.

Particularly, in the present invention, an organic acid may be used as the etching control agent. In the present invention, the term "organic acid" means an organic acid other than the compound having an amino group and a carboxyl group. The organic acid serves to improve the etching uniformity with respect to the Ti and Al films, and may be contained in an amount of 0.5 to 5% by weight based on the total weight of the composition. In the above range, it is possible to reduce the occurrence of stains in the substrate due to the lowering of the etching uniformity and to reduce the occurrence of the over-etching phenomenon with respect to the Ti and Al films.

Examples of the organic acid include butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, Pentanoic acid, and other water-soluble organic acids. These may be used singly or in combination of two or more.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are intended to further illustrate the present invention, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

Example 1 and Comparative Example 1: Preparation of Etchant Composition

180 kg of an etchant composition was prepared according to the ingredients and composition ratios shown in Table 1 below.

H ₂ O ₂ NH ₄ FHF Iminodiacetic acid nitric acid
ammonium C ₆ H ₅ N ₃ water Example 1 15 One 5 0.5 0.5 78 Comparative Example 1 15 One 5 0.5 0 78.5

(Unit: wt%)

Test example: Evaluation of etch characteristics

In the experiment, SiNx layer was deposited on glass, Ti / Al / Ti triple layer was deposited on SiNx layer, and photoresist was patterned on the triple layer.

The etchant prepared in Example 1 and Comparative Example 1 was placed in an experimental apparatus (SEMES, model name: ETCHER (TFT)) of a spray-type etch system, the temperature was set at 40 占 폚, Lt; 0 > C, the etching process was performed. Total etch time was set to 30% over etch relative to EPD. The number of treatments was from 100 sheets to 1000 sheets in 100 sheets. When the etching was completed, the specimen was injected. After the etching was completed, the substrate was rinsed with deionized water, dried using a hot air drying apparatus, and photoresist was removed using a photoresist (PR) stripper. After washing and drying, changes in side etch (critical dimension) loss were evaluated using a scanning electron microscope (SEM: model name: S-4700, manufactured by HITACHI). The results are shown in Table 2.

Etchant Side
Etch
(탆) Number of processing BLK 100 sheets 200 sheets 300 sheets 400 sheets 500 sheets 600 sheets 700 sheets 800 sheets 900 sheets 1000 sheets Example 1 1.23 1.20 1.03 0.99 0.92 0.92 0.92 0.88 0.80 0.74 0.78 Comparative Example 1 0.92 0.88 0.85 0.84 0.84 0.70 0.59 0.50 0.42 0.41 0.39

As can be seen from the above Table 2, in the case of the etching solution of Comparative Example 1, compared to the etching solution of Example 1, the decrease width of the side etching was significant and the etching straightness was remarkably decreased. On the other hand, in the case of the etching solution of Example 1, the width of the side etch was not so large as compared with that of the BLK, and the etching characteristic was excellent even in 1000 sheets.

1 is an electron micrograph showing the change in etching characteristics (Side Etch, etc.) according to the etching number as a result of etching the substrate with the etching composition of Example 1 in the above test example.

FIG. 2 is a scanning electron microscope (SEM) image showing the change in etching characteristics (Side Etch, etc.) according to the etching number as a result of etching the substrate with the etching solution composition of Comparative Example 1 in the above test example.

Claims (6)

Wherein the composition comprises 1 to 30 wt% of H ₂ O ₂ , 0.1 to 2 wt% of a fluorine compound, 1 to 10 wt% of a compound containing both an amino group and a carboxyl group simultaneously, 0.1 to 5 wt% A titanium or titanium alloy film, or a titanium or titanium alloy film and an aluminum or aluminum alloy film alternately stacked on top or bottom of an aluminum or aluminum alloy film containing 0.01 to 5% by weight of a cyclic amine compound and a residual amount of water, (3) An etching solution composition for a multi - metal film stacked on a triple layer or more. The fluorine-containing compound according to claim 1, wherein the fluorine-containing compound is a compound capable of dissociating a fluorine ion or a polyatomic fluorine ion, the fluorine-containing compound consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium bisulfide, potassium bisulfide, And at least one kind selected from the group consisting of oxides, nitrides, nitrides, nitrides, nitrides, and nitrates. [2] The compound according to claim 1, wherein the compound having an amino group and a carboxyl group is one or two compounds selected from the group consisting of alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid, Or more. The etchant composition according to claim 1, wherein the nitrate compound is at least one selected from the group consisting of ammonium nitrate, sodium nitrate, and potassium nitrate. The method of claim 1, wherein the cyclic amine compound is selected from the group consisting of pyrrolidine, pyrrole, pyrrole, indole, pyrazole, imidazole, pyrimidine, purine, pyridine, benzotriazole, Or at least two kinds thereof. 6. The composition of any one of claims 1 to 5, selected from the group consisting of butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, , Oxalic acid, and pentanoic acid. The etching solution composition according to claim 1, wherein the organic acid is at least one selected from the group consisting of oxalic acid and pentanoic acid.

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