TW201420752A - Stripper for removing photoresist - Google Patents

Abstract

The invention relates to a low-etching photo-resist stripper. The stripper comprises quaternary ammonium hydroxides, hydramine, C4-C6 polyalcohol, and solvent. The stripper could remove the photo-resist on the wafer, and inhibit the corrosion of substrates, such as aluminium, and copper. The stripper possesses the potential application with prospect in cleaning semiconductor wafer.

Description

Cleaning agent for removing photoresist

The present invention relates to a cleaning solution, and more particularly to a cleaning solution for removing photoresist.

In a conventional semiconductor manufacturing process, by forming a photoresist film on the surface of some materials, pattern transfer after exposure, after obtaining the desired pattern, it is necessary to remove the residual photoresist before proceeding to the next process. In this process it is required to completely remove the unwanted photoresist while not corroding any substrate. For example, in the wafer microsphere implantation technology, a photoresist is required to form a film which needs to be removed after the microsphere is successfully implanted, but since the photoresist is thick, it is often difficult to completely remove it. A more common method for improving the removal effect is to extend the soaking time, increase the soaking temperature, and use a more aggressive solution, but this often results in corrosion of the wafer substrate and corrosion of the microspheres, resulting in a significant reduction in wafer yield.

At present, the photoresist cleaning liquid is mainly composed of a polar organic solvent, a strong alkali, and/or water, and the photoresist on the semiconductor wafer is removed by immersing the semiconductor wafer in the cleaning liquid or rinsing the semiconductor wafer with the cleaning liquid. Such as WO2006/056298A1 utilizes an alkaline cleaning solution consisting of tetramethylammonium hydroxide (TMAH), dimethyl hydrazine (DMSO), ethylene glycol (EG) and water for cleaning the photoresist of a copper substrate while simultaneously facing the metal. Copper is substantially non-corrosive, but it is corrosive to metallic aluminum; for example, US5529887 consists of an alkaline cleaning solution consisting of potassium hydroxide (KOH), alkyl glycol monoalkyl ether, water-soluble fluoride and water, etc. The thick film photoresist on the metal and dielectric substrates was removed at 40-90 ° C in the cleaning solution. It has a high corrosion to the semiconductor wafer substrate.

It can be seen that finding a more effective method for suppressing metal corrosion suppression and high efficiency of photoresist removal is a priority for the improvement of such photoresist cleaning liquids.

The technical problem to be solved by the present invention is to provide a thick film photoresist cleaning ability and a countermeasure against the defects that the existing thick film photoresist cleaning liquid has insufficient cleaning ability or is highly corrosive to the semiconductor wafer pattern and the substrate. A semiconductor wafer pattern and a photoresist that is less corrosive to the substrate.

In order to solve the above technical problems, the present invention provides a cleaning liquid containing a quaternary ammonium hydroxide, an alcohol amine, a C ₄ -C ₆ polyol, and a solvent.

The content of the quaternary ammonium hydroxide is 0.1 to 10% by weight (% by mass), preferably 1 to 5% by weight.

Wherein the content of the alkanolamine is not more than 5% by weight, that is, less than 5% by weight.

Wherein the content of the C ₄ -C ₆ polyol is 0.1 to 10% by weight, preferably 0.1 to 5% by weight.

Wherein, the balance of the above cleaning liquid is a solvent.

The above contents are all percentage by mass; and the removal disclosed by the present invention The cleaning liquid of the photoresist residue does not contain abrasive particles.

In the present invention, the quaternary ammonium hydroxide is preferably a quaternary ammonium hydroxide including tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, methyltrisium. One or more of ethyl ammonium hydroxide and hydroxyethyl trimethyl ammonium hydroxide. In the conventional cleaning solution, sodium hydroxide, potassium hydroxide or the like is generally used as an alkaline component, but such a substance has a tendency to absorb CO ₂ in the air to generate a solid, which affects side effects such as washing, and therefore, quaternary ammonium hydroxide is used in the present application. Things.

In the present invention, the alkanolamine is preferably an alcoholamine which is monoethanolamine, diethanolamine, triethanolamine, n-propanolamine, isopropanolamine, 2-(diethylamino)ethanol, ethyldiethanolamine and diglycolamine. One or several of them. The presence of an alkanolamine is advantageous for increasing the solubility of the quaternary ammonium hydroxide.

In the present invention, the C ₄ -C ₆ polyol is preferably one or more of erythritol, xylitol, glucose, sorbitol, and mannitol.

In the present invention, the organic solvent is preferably one or more of an anthracene, an anthracene, an imidazolidinone, an imidazolidinone, or a guanamine; wherein the fluorene is preferably a dimethyl hydrazine; Butanthrone; imidazolidinone is preferably 1,3-dimethyl-2-imidazolidinone; imidazolinone is preferably 1,3-dimethyl-2-imidazolidinone; It is one or more of dimethylformamide and dimethylacetamide.

In the cleaning liquid of the present invention, the photoresist on the wafer can be cleaned at 25 ° C to 90 ° C. The specific method is as follows: The photoresist containing the photoresist is immersed in the low-etching photoresist cleaner of the present invention, and after being immersed at 25 ° C to 90 ° C for a suitable period of time, it is taken out and washed, and then dried by high-purity nitrogen gas.

The positive progress of the present invention is that the cleaning solution of the present invention has a photoresist Strong removal ability; strong corrosion inhibition for metals and non-metals; large operating space.

The advantages of the present invention are further illustrated by the following specific examples, but the scope of the present invention is not limited only to the following examples.

The polishing liquid was prepared in accordance with the ingredients of the respective examples in Tables 1 and 2 and the comparative examples, and the ratio thereof was uniformly mixed.

Effect Example 1

In order to further investigate the cleaning condition of the cleaning liquid, the present invention adopts the following technical means: immersing the wafer containing the photoresist in the cleaning agent, and oscillating at a vibration frequency of about 60 rpm at 25 to 90 ° C using a constant temperature oscillator. 5 to 60 minutes, then washed with deionized water and then dried with high purity nitrogen. The cleaning effect of the photoresist and the corrosion of the cleaning solution on the wafer are shown in Table 3.

As can be seen from Table 3, the cleaning liquid of the present invention has a good cleaning effect on the photoresist and has a wide temperature range.

As can be seen from the comparison of Example 1 with Comparative Example 1, the addition of no C ₄ -C ₆ polyol in the solution system caused moderate corrosion to the Al substrate.

It can be seen from the comparison between Example 7 and Comparative Example 7 that there is no solution in the solution system. The addition of quaternary ammonium hydroxide gives the photoresist a large amount of residue.

As can be seen from the comparison of Example 10 with Comparative Example 10, the absence of the addition of an alcoholamine in the solution system has an effect on wafer cleaning and corrosion of the substrate.

From the comparison of Examples 15 and 20 with Comparative Examples 15, 20, it can be seen that in the solution system, the content of the alkanamine exceeds 5%, and the photoresist remains, and as the content of the alcohol amine increases, the photoresist remains more.

Comparing the examples with the comparative examples, it can be seen that the examples have a good corrosion inhibiting effect on metal and non-metal substrates, and the photoresist removal ability is strong.

In summary, the positive progress of the present invention is that the cleaning liquid of the present invention has strong photoresist removal ability, strong corrosion inhibition ability to metal and non-metal, and large operation space.

It should be understood that the wt% of the present invention refers to the mass percentage content.

The specific embodiments of the present invention have been described in detail above, but are merely exemplary, and the invention is not limited to the specific embodiments described above. Any equivalent modifications and substitutions to the invention are also within the scope of the invention. Accordingly, equivalents and modifications may be made without departing from the spirit and scope of the invention.

Claims (13)

A photoresist-removing cleaning solution comprising a quaternary ammonium hydroxide, an alcohol amine, a C ₄ -C ₆ polyol, and a solvent. The cleaning solution according to claim 1, wherein the quaternary ammonium hydroxide is contained in an amount of 0.1 to 10% by weight. The cleaning solution according to claim 2, wherein the quaternary ammonium hydroxide is contained in an amount of from 1 to 5% by weight. The cleaning solution according to claim 1, wherein the content of the alcoholamine is less than 5% by weight. The cleaning solution according to claim 1, wherein the C ₄ -C ₆ polyol is contained in an amount of 0.1 to 10% by weight. The cleaning solution according to claim 5, wherein the C ₄ -C ₆ polyol is contained in an amount of 0.1 to 5 wt%. The cleaning liquid according to claim 1, wherein the remaining amount in the cleaning liquid is a solvent. The cleaning solution according to claim 1, wherein the quaternary ammonium hydroxide is selected from the group consisting of quaternary ammonium hydroxides including tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylate. One or more of ammonium hydroxide, methyltriethylammonium hydroxide, and hydroxyethyltrimethylammonium hydroxide. The cleaning solution according to claim 1, wherein the alcohol amine is selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, n-propanolamine, isopropanolamine, 2-(diethylamino)ethanol, and ethyldiethanolamine. And one or more of diethylene glycol amines. The cleaning solution according to claim 1, wherein the C ₄ -C ₆ polyol is selected from the group consisting of erythritol, xylitol, glucose, sorbitol, and mannitol. The cleaning solution according to claim 1, wherein the solvent is one or more of an anthraquinone, an anthracene, an imidazolidinone, an imidazolidinone, and a guanamine. The cleaning solution according to claim 11, wherein the hydrazine is dimethyl hydrazine; the hydrazine is cyclobutyl hydrazine; and the imidazolidinone is 1,3-dimethyl-2-imidazole The alkyl ketone; the imidazolidinone is 1,3-dimethyl-2-imidazolidinone; and the guanamine is one or more selected from the group consisting of dimethylformamide and dimethylacetamide. The cleaning liquid of claim 1, wherein the cleaning liquid does not contain abrasive particles.