TW201623599A - Cleaning liquid for removing photoetching residue - Google Patents

Abstract

The invention reveals one kind of cleaning liquid used for removing photoetching residue and its component, which is not containing fluoride and hydroxylamine. This cleaning liquid with low etching ability contains (a) alcohol amine, (b)solvent, (c)water, (d)phenols, (e)alkynol ethoxylates, (f)hydrazine and its derivatives, (g)polyols. This cleaning liquid with low etching performance can fast remove the photo resist which cross-hardening after complicate chemical reacting induced by roasting, dry etching, cineration and plasma implantation, and it also can remove the photo-resist residue on metal line, interlock pore and pad of the wafer, but not affect the substrate materials, such as Aluminum, Copper, Silica and etc. The cleaning liquid revealed in the invention has a potential application prospect in washing semi-conductive chips field.

Description

Resistive residue cleaning solution

The invention discloses a photoresist residue cleaning liquid, in particular to a cleaning liquid which does not contain hydroxylamine and fluoride.

In the fabrication of semiconductor components, the application, exposure and imaging of the photoresist layer are necessary process steps for the pattern fabrication of the components. The residue of the photoresist layer material needs to be completely removed before the next process step (ie, after coating, imaging, ion implantation, and etching of the photoresist layer). Generally, dozens of photolithography processes are used in the process of a semiconductor device, and since the ions and radicals of the plasma etching gas cause a complicated chemical reaction with the photoresist, the photoresist is rapidly hardened by crosslinking with the inorganic material, so that the photoresist layer It becomes less soluble and thus more difficult to remove. Up to now, in the semiconductor manufacturing industry, this layer of photoresist film has been removed using a two-step process (dry ashing and wet etching). The first step utilizes dry ashing to remove most of the photoresist layer (PR); the second step uses the corrosion inhibitor composition wet etch/clean process to remove and clean the remaining photoresist layer, typically in the form of a cleaning solution. / rinse / dry. Only the residual polymer photoresist layer and inorganic matter can be removed in this process, and the damage to the metal layer such as the aluminum layer cannot be attacked.

In the current wet cleaning process, the most used cleaning solution is a cleaning liquid containing hydroxylamines and fluorine-containing cleaning liquids. Typical patents of hydroxylamine cleaning liquids are US6319885, US5672577, US6030932, US6825156, US5419779 and US6777380B2. Wait. After continuous improvement, the corrosion rate of the solution itself to the metal aluminum has been greatly reduced, but this kind of cleaning liquid has a single source and is easy to explode due to the use of hydroxylamine. However, existing fluoride-based cleaning solutions have been greatly improved, such as US 5,972,862, US 6,828,289, etc., but there is still a good control of the corrosion of metal and non-metal substrates at the same time, and it is easy to cause channel characteristics after cleaning. On the other hand, because some semiconductor companies use wet cleaning equipment made of quartz, and the fluorine-containing cleaning solution corrodes quartz and increases corrosion with increasing temperature, it is not compatible with existing quartz equipment. The problem of tolerance affects its widespread use.

Although the above two types of cleaning fluids have been relatively successfully used in the semiconductor industry, due to their respective limitations and shortcomings, the industry has developed a third type of cleaning solution that contains neither hydroxylamine nor fluoride. . For example, US Pat. No. 5,981,454 A discloses an acidic cleaning solution containing an organic acid and an alkanolamine having a pH of 3.5 to 7. The cleaning solution is highly capable of removing the photoresist of the metal layer and the conductive medium layer. For example, US 6,103,680 A discloses a cleaning solution containing a low alkyl chain hydroxy hydrazine, water, a carboxylic acid compound and a water-soluble organic solvent which is substantially non-corrosive to the metal and which is effective in removing the plasma-etched residue. This kind of cleaning solution containing neither hydroxylamine nor fluoride can solve the problem of single source and safety and environmental protection of hydroxylamine, and solve the problem of unstable corrosion rate of non-metal of fluorine-containing cleaning liquid. However, such cleaning fluids often have great limitations in their use. Thus, while some cleaning fluid compositions have been disclosed, there is a need and a greater need to prepare such a cleaning fluid that is more versatile.

The object of the present invention is to provide a low-cost semiconductor wafer cleaning solution capable of removing photoresist residue on a wafer, which does not contain hydroxylamine and fluoride; has a low rate of corrosion to metals and non-metals; Compatible.

An aspect of the present invention provides a photoresist residue cleaning solution containing an alcohol amine, a solvent, water, a phenol, an acetylene alcohol ethoxylate, a polyol, a hydrazine, and a derivative thereof. Things. That is, the photoresist residue cleaning solution includes at least the following components: i.

Ii. Solvent

Iii. water

Iv. Phenols

V.alkynyl alcohol ethoxylate

Polyol

Vii. 肼 and its derivatives.

Wherein, the aforementioned alcohol amine is preferably an aliphatic alcohol amine, more preferably monoethanolamine, N-methylethanolamine, diethanolamine, triethanolamine, isopropanolamine, N,N-dimethylethanolamine One or more of N-(2-aminoethyl)ethanolamine and diglycolamine. The concentration is preferably from 10% to 70%, preferably from 10% to 60%.

Further, wherein the solvent is a solvent conventional in the art, preferably one or more selected from the group consisting of anthraquinone, anthracene, imidazolidinone, pyrrolidone, imidazolidinone, ether and decylamine. Wherein, the hydrazine is preferably dimethyl hydrazine; the hydrazine is preferably cyclobutyl hydrazine; and the imidazolidinone is preferably 1,3- dimethyl-2-imidazole. The alkyl ketone; the pyrrolidone is preferably N-methylpyrrolidone; the imidazolidinone is preferably 1,3-dimethyl-2-imidazolidinone (DMI); It is dipropylene glycol methyl ether; the guanamine is preferably N,N-dimethylacetamide. The concentration is preferably from 10% to 60%, preferably from 10% to 50%.

Wherein, the phenols are preferably polyhydric phenols, more preferably catechol, hydroquinone, resorcinol, pyrogallol, 5-methoxy pyrogallol, 5- One or more of tert-butyl pyrogallol and 5-hydroxymethyl pyrogallol. The concentration is preferably from 0.1 to 10%; preferably from 0.5 to 5%.

Further, among the above, the ruthenium and its derivatives are preferably hydrazine hydrate, benzamidine, 2-hydroxyethyl hydrazine, carbon hydrazine, salicylide, valerian, bismuth succinate, and propylene. One or more of the cockroaches. The concentration is preferably from 0.05 to 10%, preferably from 0.1 to 5%.

Wherein, the above polyol is preferably an alkyl polyol, more preferably glycerol, pentaerythritol, xylitol, sorbitol, diethylene glycol, dipropylene glycol, 2-hydroxymethane- One or more of 2-methyl-1,3 propanediol. The concentration is preferably from 0.05 to 10%, preferably from 0.1 to 5%.

Further, wherein the alkynol ethoxylate is preferably a propynyl alcohol ethoxylate, a butynediol ethoxylate, 2,4,7,9-tetramethyl-5-decyne-4,7 One or more of the diol ethoxylates. The concentration is preferably from 0.05 to 5%, preferably from 0.1 to 3%.

Further, wherein the water concentration is preferably less than 40%, preferably 5 to 35%. The water may preferably be deionized water, distilled water, ultrapure water, or water by which impurity ions are removed by means.

The above contents are all percentage by mass; the cleaning solution for removing the photoresist residue does not contain abrasive particles, hydroxylamine, fluoride and oxidant.

In the cleaning liquid of the present invention, the photoresist residue on the wafer can be cleaned at 50 ° C to 80 ° C. The specific method is as follows: the wafer containing the photoresist residue is immersed in the cleaning liquid in the present invention, and immersed at 50 ° C to 80 ° C for a suitable period of time, taken out and rinsed, and then blown dry with high-purity nitrogen gas.

The technical effects of the present invention are:

1) The cleaning solution of the present invention can effectively remove metal, via and metal pads by an effective combination of phenols, polyols, hydrazine and its derivatives, and acetylenic ethoxylates. (Pad) Photoresist residue on the wafer simultaneously suppresses corrosion of metallic aluminum and non-metal.

2) The cleaning solution of the invention solves the problems of single source, high price and easy explosion of hydroxylamine in the traditional hydroxylamine cleaning solution;

3) The cleaning liquid of the invention has low non-metal corrosion rate; solves the problem that the non-metal corrosion rate of the conventional fluorine-based cleaning liquid is unstable, and is compatible with the quartz cleaning tank commonly used by semiconductor manufacturers.

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 reagents and starting materials used in the present invention are commercially available. The cleaning liquid of the present invention can be obtained by simply and uniformly mixing the above components.

Effect embodiment

In order to further investigate the cleaning of such a cleaning liquid, the present invention adopts the following technical means: a metal wafer, a via wafer, and a metal pad wafer containing a photoresist residue, respectively. Immerse in the cleaning solution, oscillate at 50 ° C to 80 ° C for 10 to 40 minutes at a vibration frequency of about 60 rpm using a constant temperature oscillator, then rinse with a high purity nitrogen gas. The cleaning effect of the photoresist residue and the corrosion of the cleaning solution on the wafer are shown in Table 2.

As can be seen from Table 2, the cleaning liquid of the present invention has a good cleaning effect on metal wafers, via wafers and metal pad wafers containing photoresist residues, and the use temperature. It has a wide range and does not corrode metal aluminum and non-metal cerium oxide. As can be seen from Comparative Example 1 and Example 1, in the case where no alcoholamine was added, there was more residual residue on the surface of the wafer which could not be removed. As can be seen from Comparative Example 2 and Example 2, the lack of solvent in the formulation caused the photoresist residue on the wafer to be completely removed. It can be seen from Comparative Example 3 and Example 5 that in the case where the remaining components and cleaning conditions are completely the same, the lack of phenols will cause severe corrosion to the metal aluminum, and the wafer cannot be obtained at the same time. The photoresist residue on the top is completely removed. It can be seen from Comparative Example 4 and Example 6 that in the case where the other components are identical and the cleaning operation conditions are the same, if aluminum and its derivatives are not added, corrosion of the metal aluminum occurs. It can be seen from Comparative Example 5 and Example 8 that the addition of the polyol contributes to the protection of the metallic aluminum and the removal of the photoresist residue. It can be seen from Comparative Example 6 and Example 10 that in the case where the other components are identical and the cleaning conditions are completely the same, the addition of the propynyl alcohol ethoxylate will affect the removal of the photoresist residue on the wafer, resulting in a part. Resist residues cannot be removed. From the comparison results of the above comparative examples and the examples, it is understood that the components in the cleaning solution of the present application support each other and cooperate with each other, so that the photoresist residue can be removed without causing corrosion to the substrate.

In summary, the positive progress of the present invention is that the cleaning solution of the present invention is capable of removing photoresist residues on metal, via and pad wafers while substantially no substrate Attacks have good application prospects in the field of semiconductor wafer cleaning.

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

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 (26)

A photoresist residue cleaning solution comprising an alcohol amine, a solvent, water, a phenol, an acetylenic ethoxylate, a polyol, a hydrazine and a derivative thereof, and the cleaning solution does not contain fluoride and / or hydroxylamine. The cleaning solution according to claim 1, wherein the alcohol amine is an aliphatic alcohol amine. The cleaning solution according to claim 2, wherein the alcohol amine is selected from the group consisting of monoethanolamine, N-methylethanolamine, diethanolamine, triethanolamine, isopropanolamine, N,N-dimethylethanolamine, N-( One or more of 2-aminoethyl)ethanolamine and diglycolamine. The cleaning solution according to claim 1, wherein the alcohol amine concentration is 10% to 70% by mass. The cleaning solution according to claim 4, wherein the alcohol amine concentration is 10-60% by mass. The cleaning solution according to claim 1, wherein the solvent is one or more selected from the group consisting of anthraquinone, anthracene, imidazolidinone, pyrrolidone, imidazolidinone, ether, and decylamine. The cleaning solution according to claim 6, wherein the hydrazine is dimethyl hydrazine; the hydrazine is cyclobutyl hydrazine; and the imidazolidinone is 1,3-dimethyl-2- An imidazolidinone; the pyrrolidone is N-methylpyrrolidone; the imidazolidinone is 1,3-dimethyl-2-imidazolidinone; the ether is dipropylene glycol methyl ether; The amine is N,N-dimethylacetamide. The cleaning solution according to claim 1, wherein the solvent concentration is 10% to 60% by mass. The cleaning solution according to claim 8, wherein the solvent concentration is 10% to 50% by mass. The cleaning solution according to claim 1, wherein the phenol is a polyhydric phenol. The cleaning solution according to claim 10, wherein the phenol is catechol, p-benzoic acid One or more of phenol, resorcinol, pyrogallol, 5-methoxy pyrogallol, 5-tert-butyl pyrogallol, 5-hydroxymethyl pyrogallol. The cleaning solution according to claim 1, wherein the phenolic concentration is 0.1-10% by mass. The cleaning solution according to claim 12, wherein the phenolic concentration is 0.5-5% by mass. The cleaning solution according to claim 1, wherein the hydrazine and its derivatives are hydrazine hydrate, benzamidine, 2-hydroxyethyl hydrazine, carbon hydrazine, salicylate, valerian, succinic acid. One or several of two or two. The cleaning solution according to claim 1, wherein the concentration of the hydrazine and its derivative is 0.05-10% by mass. The cleaning solution according to claim 15, wherein the concentration of the hydrazine and its derivative is 0.1 to 5% by mass. The cleaning solution according to claim 1, wherein the polyol is an alkyl polyol. The cleaning solution according to claim 17, wherein the polyol is glycerol, pentaerythritol, xylitol, sorbitol, diethylene glycol, dipropylene glycol, 2-hydroxymethane-2-methyl One or more of benzyl-1,3 propanediol. The cleaning solution according to claim 1, wherein the polyol concentration is 0.05-10% by mass. The cleaning solution according to claim 19, wherein the polyol concentration is 0.1 to 5% by mass. The cleaning solution according to claim 1, wherein the acetylenic ethoxylate is propynyl ethoxylate, butynediol ethoxylate, 2,4,7,9-tetramethyl One or more of -5-decyne-4,7-diol ethoxylate. The cleaning solution according to claim 1, wherein the acetylenic ethoxylate has a concentration of 0.05 to 5% by mass. The cleaning solution according to claim 22, wherein the acetylenic ethoxylate has a concentration of 0.1 to 3% by mass. The cleaning solution according to claim 1, wherein the water concentration is less than 40% by mass. The cleaning liquid according to claim 1, wherein the water concentration is 5 to 35% by mass. Use of the cleaning solution of any of claims 1-26 for removing photoresist residues.