JPH06184595A - Detergent for resist removing step - Google Patents

Abstract

PURPOSE:To obtain the subject detergent which exhibits excellent detergency for a resist remover and is soluble in water, lowly toxic and excellent in handleability, etc., by using a specified hydroxycarboxylic acid ester as the essential constituent. CONSTITUTION:This detergent is produced by mixing at least one hydroxycarboxylic acid ester selected from an alkyl glycolate, an alkyl alpha- hydroxyisobutyrate and an alkyl beta-hydroxypropionate with at least one of water, pyrrolidone, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, methyl acetate, ethyl acetate, methyl lactate, ethyl lactate, etc. Since this detergent is soluble in water, it makes it possible to proceed to the step of washing with water without the hitherto required steps of washing with a lipophilic solvent and then with a hydrophilic solvent, so that the process steps can be curtailed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning agent for a substrate in a fine pattern forming process, and more specifically, a cleaning agent suitable for cleaning the residue of the releasing agent adhering to the substrate after the resist is removed. It is about. The fine pattern forming process is used in many situations such as semiconductor manufacturing and liquid crystal display manufacturing.

[0002]

2. Description of the Related Art In the fine pattern forming step, when a fine pattern is formed on a substrate, a resist is applied, and a resist which is no longer necessary after undergoing processes such as exposure, development and etching is removed. It is removed from the substrate using a resist stripper. For the resist stripper, a chlorine-based solvent (tetrachloroethylene, O-dichlorobenzene, etc.) and alkylbenzene sulfonic acid, or a combination of alkylbenzene and alkylbenzene sulfonic acid is widely used for positive and negative resists. There is. For positive resist, a combination of glycol ethers (butyldiglycol, methicellosolve, etc.), pyrrolidones (N-methylpyrrolidone, etc.) or sulfoxides (dimethylsulfoxide, etc.) and alkanolamines is widely used.

In the step of removing the resist using the above-mentioned stripping solution, for positive / negative, the substrate is first dipped in a stripping solution which has been heated, then washed with a lipophilic solvent such as alkylbenzene, and then a hydrophilic solvent. The steps of washing with methanol, isopropyl alcohol, etc., and then washing with water are adopted. For the positive type, a step of immersing the substrate in a heated stripping solution, immediately washing with a hydrophilic solvent such as methanol or isopropyl alcohol, and then washing with water is adopted.

However, in such a method, the process is complicated, alkylbenzene and the like have an unpleasant odor, toxicity is great and there is a safety and health problem, and hydrophilic methanol and isopropyl alcohol have a low flash point and are a handling problem. There is.

[0005]

The object of the present invention is not only excellent in cleaning power but also excellent in safety without toxicity and unpleasant odor, and moreover, the release agent residue on the substrate can be easily removed by cleaning. It is an object of the present invention to provide a novel cleaning agent for a resist stripping process that can shorten the process.

[0006]

Means for Solving the Problems That is, one of the present invention is to provide at least one hydroxycarboxylic acid selected from glyco-alkyl acid alkyl ester, α-hydroxyisobutyric acid alkyl ester and β-hydroxypropionic acid alkyl ester. The present invention relates to a cleaning agent for a resist stripping process containing an ester.

According to another aspect of the present invention, at least one hydroxycarboxylic acid ester selected from glyco-acid alkyl ester, α-hydroxyisobutyric acid alkyl ester and β-hydroxypropionic acid alkyl ester, and water, pyrrolidone, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, methyl acetate,
A cleaning agent for a resist stripping step containing at least one selected from ethyl acetate, methyl lactate, ethyl lactate, methyl α-methoxyisobutyrate, methyl β-methoxyisobutyrate, γ-butyrolactone, dimethylsulfoxide and sulfolane. .

The present invention will be described in detail below. The cleaning agent in the present invention is mainly composed of hydroxycarboxylic acid ester. Examples of the hydroxycarboxylic acid ester include methyl glycolate, ethyl glycolate, isopropyl glycolate, butyl glycolate, methyl α-hydroxyisobutyrate, ethyl α-hydroxyisobutyrate, and isopropyl α-hydroxyisobutyrate. , Butyl α-hydroxyisobutyrate, methyl β-hydroxypropionate, ethyl β-hydroxypropionate, isopropyl β-hydroxypropionate and methyl lactate butyl β-hydroxypropionate are used. These hydroxycarboxylic acid esters may be used alone or in combination of two or more kinds.

The concentration of the hydroxycarboxylic acid ester used in the present invention is preferably 50% or more. When the hydroxycarboxylic acid ester concentration is less than 50%, the cleaning properties, safety, operability, etc., which are the features of the present invention, are gradually impaired.

In the cleaning agent of the present invention, in addition to the above-mentioned hydroxycarboxylic acid ester, other hydrophilic organic solvent or a solvent of the second component such as water can be used in combination, thereby controlling the cleaning ability. You can

The hydrophilic organic solvent used in combination is not particularly limited, but preferred examples include pyrrolidone, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, methyl acetate, ethyl acetate, methyl lactate, ethyl lactate, α. -Methyl methoxyisobutyrate, β-
Methyl methoxyisobutyrate, γ-butyrolactone, dimethyl sulfoxide, sulfolane and the like can be mentioned. These second component solvents can be used in combination of two or more kinds. The concentration of the solvent of the second component is preferably 50% by weight or less.

Further, a surfactant may be used in combination for improving the detergency. Examples of the surfactant include alkyl sulfate ester salts, alkylphenol polyalkylene ethers, and sulfosuccinates.

The resist and the resist remover applicable to the cleaning agent of the present invention are not particularly limited and can be arbitrarily selected from those usually used. However, as the resist remover exhibiting a particularly remarkable cleaning effect, , Alkylbenzene sulfonic acid, alkylbenzene, alkylnaphthalene, phenol, alkylphenol, chlorine-based solvent,
Those containing chlorobenzene as a component, or ethanolamine, glycol ether, pyrrolidone-based solvent,
Examples thereof include those containing alkyl sulfoxide, sulfolane and the like.

[0014]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

Examples 1 to 12 Commercially available positive photoresist was applied on a silicon wafer by spin coating to a thickness of 1.5 μm and baked at 100 ° C. for 2 minutes on a hot plate to form a photoresist film. Formed. This photoresist-added silicon wafer is placed in a stripping solution of [A] dodecylbenzenesulfonic acid 20% by weight + alkylbenzene 80% by weight or [B] monoethanolamine 50% by weight + butyldiglycol 50% by weight at 80 ° C for 10 minutes. Immersion, then washing with each of the cleaning agents of the present invention shown in Table 1, followed by washing with water, the amount of residue adhered on the wafer was measured, and the cleaning power was evaluated.

Comparative Examples 1 and 2 For comparison, a silicon wafer having a photoresist film formed thereon was dipped in the stripping solution of the above [A] or [B], and then xylene or After washing with isopropyl alcohol and then washing with water, the amount of the residue adhered on the wafer was measured to evaluate the washing power.

The results are shown in Table 1. In addition, the measurement of the residual adhesion amount was judged visually and by a metallurgical microscope. ◯: No residue visually or with a metallographic microscope Δ: No residue visually, but with a metallographic microscope ×: visually residual

[0018]

[0019]

The cleaning agent for the resist stripping process of the present invention is
It has excellent detergency for each release agent, and because it is water-soluble, it can be moved to the water washing step without the conventional washing step from a lipophilic solvent to a hydrophilic solvent, greatly reducing the step. Be peeled off. In addition, since it is based on hydroxycarboxylic acid ester, it has low toxicity, no unpleasant odor, has a relatively high flash point, and significantly improves operability and safety.

Claims (3)

[Claims] 1. A cleaning agent for a resist stripping process, which contains at least one hydroxycarboxylic acid ester selected from glyco-acid alkyl ester, α-hydroxyisobutyric acid alkyl ester and β-hydroxypropionic acid alkyl ester. 2. At least one hydroxycarboxylic acid ester selected from glyco-acid alkyl ester, α-hydroxyisobutyric acid alkyl ester and β-hydroxypropionic acid alkyl ester, and water, pyrrolidone, N-methylpyrrolidone, dimethylformamide. , Dimethylacetamide, methyl acetate, ethyl acetate, methyl lactate, ethyl lactate, α-methoxyisobutyrate, β-
A cleaning agent for a resist stripping process, which contains at least one selected from methyl methoxyisobutyrate, γ-butyrolactone, dimethyl sulfoxide and sulfolane. 3. The hydroxycarboxylic acid ester is methyl glycolate, ethyl glycolate, isopropyl glycolate, butyl glycolate, methyl α-hydroxyisobutyrate, ethyl α-hydroxyisobutyrate, α. Washing according to claim 1 or 2, which is isopropyl hydroxyisobutyrate, butyl α-hydroxyisobutyrate, methyl β-hydroxypropionate, ethyl β-hydroxypropionate, isopropyl β-hydroxypropionate or butyl β-hydroxypropionate. Agent.