阅读说明：本技术 用于化学机械抛光后的非tmah碱清洗液及其制备方法 (non-TMAH alkali cleaning solution used after chemical mechanical polishing and preparation method thereof ) 是由 王溯 马丽 史筱超 秦长春 何加华 马伟 王亮 杨跃 于 2019-09-30 设计创作，主要内容包括：本发明公开了一种用于化学机械抛光后的非TMAH碱清洗液及其制备方法。本发明的种清洗液由下述原料制得,所述的原料包括下列质量分数的组分：0.01％-25％的碱、0.01％-30％的醇胺、0.001％-1％的抗氧化物、0.01％-10％的缓蚀剂、0.01％-10％的螯合剂、0.01％-5％的表面活性剂、和水,水补足余量。本发明的清洗液对铜、钴和钨缓蚀性优良、稳定性好、毒性小、生物兼容性强以及环保性较佳。(The invention discloses a non-TMAH alkali cleaning solution used after chemical mechanical polishing and a preparation method thereof. The cleaning solution is prepared from the following raw materials in parts by mass: 0.01-25% of alkali, 0.01-30% of alcohol amine, 0.001-1% of antioxidant, 0.01-10% of corrosion inhibitor, 0.01-10% of chelating agent, 0.01-5% of surfactant, water and the balance of water. The cleaning solution disclosed by the invention has the advantages of excellent corrosion inhibition on copper, cobalt and tungsten, good stability, low toxicity, strong biocompatibility and better environmental friendliness.)

1. The cleaning solution is characterized by being prepared from the following raw materials in parts by mass: 0.01-25% of alkali, 0.01-30% of alcohol amine, 0.001-1% of antioxidant, 0.01-10% of corrosion inhibitor, 0.01-10% of chelating agent, 0.01-5% of surfactant and water, wherein the balance is water, and the mass fraction is the mass percentage of each raw material in the total mass of the raw materials;

wherein the base is one or more of a compound of formula I, 1, 8-diazabicyclo [5.4.0] undec-7-ene, 1, 5-diazabicyclo [4.3.0] non-5-ene, 1, 8-bisdimethylaminonaphthalene, 3, 7-diazabicyclo [3.3.1] nonane, triethylenediamine, and hexamethonium hydroxide;

in the formula I, X is N or P; r¹、R²And R³Independently is C₁～C₃Alkyl or hydroxy substituted C₁～C₃An alkyl group; r⁴Is C₁～C₄Alkyl radical, R^4-1Substituted C₁～C₄Alkyl radical, C₂～C₃Alkenyl, adamantyl, phenyl, 3- (trifluoromethyl) phenyl, benzyl or

R^4-1Is hydroxy, C₁～C₃Alkyl or hydroxy substituted C₁～C₃An alkyl group; r^4-1Is 1 or more; when R is^4-1When there are plural, R^4-1The same or different;

R¹、R²、R³and R⁴Not methyl or n-propyl at the same time.

2. The cleaning solution of claim 1, wherein in formula I, when R is¹、R²And R³Independently is C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl, ethyl, n-propyl or isopropyl;

and/or, in formula I, when said R is¹、R²And R³Independently is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl, ethyl, n-propyl or isopropyl;

and/or, in formula I, when said R is⁴Is C₁～C₄When alkyl, said C₁～C₄Alkyl is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl or tert-butylA group;

and/or, in formula I, when said R is⁴Is C₂～C₃When alkenyl, said C₂～C₃Alkenyl is vinyl, propenyl or allyl;

and/or, in formula I, when said R is⁴Is R^4-1Substituted C₁～C₄When alkyl, said C₁～C₄Alkyl is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl or tert-butyl;

and/or, in formula I, when said R is^4-1Is C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl, ethyl, n-propyl or isopropyl;

and/or, in formula I, when said R is^4-1Is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl, ethyl, n-propyl or isopropyl;

and/or, in formula I, R^4-12 or 3;

and/or, in formula I, X is N.

3. The cleaning solution of claim 2, wherein in formula I, when R is¹、R²And R³Independently is C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl or ethyl;

and/or, in formula I, when said R is¹、R²And R³Independently is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃Alkyl is ethyl;

and/or, in formula I, when said R is⁴Is C₁～C₄When alkyl, said C₁～C₄Alkyl is tert-butyl;

and/or, in formula I, when said R is⁴Is C₂～C₃When alkenyl, said C₂～C₃Alkenyl vinyl or allyl;

and/or, in formula I, when said R is⁴Is R^4-1Substituted C₁～C₄When alkyl, said C₁～C₄Alkyl is ethyl, n-propyl or n-butyl;

and/or, in formula I, when said R is^4-1Is C₁～C₃When alkyl, said C₁～C₃Alkyl is methyl;

and/or, in formula I, when said R is^4-1Is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃The alkyl group is a methyl group.

4. The cleaning solution according to claim 1, wherein the mass fraction of the alkali in the cleaning solution is 1-20%, preferably 5-15%;

and/or, in the cleaning solution, the mass fraction of the alcohol amine is 1-10%, preferably 5-8%;

and/or, in the cleaning solution, the mass fraction of the antioxidant is 0.002-0.100%, preferably 0.005-0.010%;

and/or, in the cleaning solution, the mass fraction of the corrosion inhibitor is 0.1-1.0%, preferably 0.5-0.8%;

and/or, in the cleaning solution, the mass fraction of the chelating agent is 0.1-1.0%, preferably 0.3-0.9%;

and/or, in the cleaning solution, the mass fraction of the surfactant is 0.1-1.0%, preferably 0.2-0.7%.

5. The cleaning solution of claim 1, wherein the base in the cleaning solution is a compound of formula I;

and/or the alcohol amine is one or more of monoethanolamine, diglycolamine, triethanolamine, isobutanolamine and isopropanolamine;

and/or, in the cleaning solution, the antioxidant is a reducing agent and/or a reductive enzyme preparation, preferably a reductive enzyme preparation;

and/or in the cleaning solution, the corrosion inhibitor is one or more of 2-mercaptobenzothiazole, catechol, pyrogallol and 5-aminotetrazole;

and/or in the cleaning solution, the chelating agent is one or more of malonic acid, maleic acid, arginine and ethylene diamine tetraacetic acid;

and/or, in the cleaning solution, the surfactant is an ionic surfactant;

and/or in the cleaning solution, the water is one or more of deionized water, pure water and ultrapure water.

6. The cleaning solution according to claim 5, wherein the alkali in the cleaning solution is

and/or, in the cleaning liquid, when the antioxidant is a reducing agent, the reducing agent is ascorbic acid;

and/or, in the cleaning solution, when the antioxidant is a reductive enzyme preparation, the reductive enzyme preparation is one or more of superoxide dismutase, glutathione peroxidase, thioredoxin peroxidase, succinate dehydrogenase, sulfite reductase and nitrite reductase; the superoxide dismutase is preferably copper and zinc containing superoxide dismutase;

and/or in the cleaning liquid, when the surfactant is an ionic surfactant, the ionic surfactant is an anionic surfactant and can be one or more of dodecyl benzene sulfonic acid, isooctyl alcohol sodium sulfate and phenol polyoxyethylene ether sodium sulfate.

7. The cleaning solution according to any one of claims 1 to 6, which is prepared from the following raw materials: said base, said alcohol amine, said antioxidant, said corrosion inhibitor, said chelating agent, said surfactant, and said water.

8. A method for preparing the cleaning liquid according to any one of claims 1 to 7, characterized by comprising the steps of: and mixing the raw materials to obtain the cleaning solution.

9. Use of the cleaning solution according to any one of claims 1 to 7 for cleaning a semiconductor device after chemical mechanical polishing; preferably, the chemically mechanically polished substrate is one or more of a copper interconnect substrate, a cobalt interconnect substrate and a tungsten interconnect substrate.

10. Use of a base according to any one of claims 1 to 7 in chemical mechanical polishing cleaning; preferably, the chemically mechanically polished substrate is one or more of a copper interconnect substrate, a cobalt interconnect substrate and a tungsten interconnect substrate.

Technical Field

The invention relates to a non-TMAH alkali cleaning solution used after chemical mechanical polishing and a preparation method thereof.

Background

Metal materials such as copper, aluminum, tungsten, etc. are commonly used as conductive line materials in integrated circuits. Chemical Mechanical Polishing (CMP) is a major technique for wafer planarization in the fabrication of devices. The metal chemical mechanical polishing solution generally contains abrasive particles, a complexing agent, a metal corrosion inhibitor, an oxidizing agent, and the like. The abrasive particles are mainly silicon dioxide, aluminum oxide, aluminum-doped or aluminum-coated silicon dioxide, cerium dioxide, titanium dioxide, polymer abrasive particles, and the like. After the metal CMP process, the wafer surface is contaminated with metal ions and abrasive particles themselves in the slurry, which can affect the electrical characteristics of the semiconductor and the reliability of the device. The residues of these metal ions and abrasive particles can affect the flatness of the wafer surface, which can degrade device performance and affect subsequent processing or device operation. Therefore, it is very necessary to remove metal ions, metal corrosion inhibitors and abrasive particles remaining on the wafer surface after the metal CMP process, to improve the hydrophilicity of the cleaned wafer surface, and to reduce surface defects.

The main component of the post-CMP cleaning solution in the market at present is tetramethylammonium hydroxide (TMAH), which has strong basicity, volatility and toxicity, poor biocompatibility, poor environmental protection performance, strong corrosivity and corrosion inhibition to be improved.

The raw materials of the cleaning solution capable of replacing the quaternary ammonium hydroxide are urgently needed to be developed, and the cleaning solution is required to improve the environmental protection performance, the cleaning performance, the corrosion inhibition performance and the storage stability.

Disclosure of Invention

The invention aims to solve the technical problems of high toxicity, poor biocompatibility, poor environmental protection performance, strong corrosivity and poor corrosion inhibition caused by large consumption of TMAH in the existing cleaning solution, and provides a non-TMAH alkaline cleaning solution used for chemical mechanical polishing and a preparation method thereof. The cleaning solution avoids the use of TMAH, and has the advantages of excellent corrosion inhibition, good stability, low toxicity, strong biocompatibility, good environmental protection performance and the like.

The present invention mainly solves the above-mentioned problems by the following technical means.

The invention provides a cleaning solution which is prepared from the following raw materials in parts by mass: 0.01-25% of alkali, 0.01-30% of alcohol amine, 0.001-1% of antioxidant, 0.01-10% of corrosion inhibitor, 0.01-10% of chelating agent, 0.01-5% of surfactant and water, wherein the balance is water, and the mass fraction is the mass percentage of each raw material in the total mass of the raw materials;

wherein the base is one or more of a compound of formula I, 1, 8-diazabicyclo [5.4.0] undec-7-ene, 1, 5-diazabicyclo [4.3.0] non-5-ene, 1, 8-bisdimethylaminonaphthalene, 3, 7-diazabicyclo [3.3.1] nonane, triethylenediamine, and hexamethonium hydroxide;

in the formula I, X is N or P; r¹、R²And R³Independently is C₁～C₃Alkyl or hydroxy substituted C₁～C₃An alkyl group; r⁴Is C₁～C₄Alkyl radical, R^4-1Substituted C₁～C₄Alkyl radical, C₂～C₃Alkenyl, adamantyl, phenyl, 3- (trifluoromethyl) phenyl, benzyl or

R^4-1Is hydroxy, C₁～C₃Alkyl or hydroxy substituted C₁～C₃An alkyl group; r^4-1Is 1 or more; when R is^4-1When there are plural, R^4-1The same or different;

R¹、R²、R³and R⁴Not methyl or n-propyl at the same time.

In the formula I, when R is¹、R²And R³Independently is C₁～C₃When alkyl, said C₁～C₃The alkyl group may be a methyl group, an ethyl group, an n-propyl group or an isopropyl group, and may also be a methyl group or an ethyl group.

In the formula I, when R is¹、R²And R³Independently is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃The alkyl group may be a methyl group, an ethyl group, an n-propyl group or an isopropyl group, and may also be an ethyl group.

In the formula I, when R is⁴Is C₁～C₄When alkyl, said C₁～C₄The alkyl group may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or a tert-butyl group.

In the formula I, when R is⁴Is C₂～C₃When alkenyl, said C₂～C₃The alkenyl group may be a vinyl group, a propenyl group or an allyl group, and may also be a vinyl group or an allyl group.

In the formula I, when R is⁴Is R^4-1Substituted C₁～C₄When alkyl, said C₁～C₄The alkyl group may be a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group or a tert-butyl group, or an ethyl group, a n-propyl group or a n-butyl group.

In the formula I, when R is^4-1Is C₁～C₃When alkyl, said C₁～C₃The alkyl group may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or a methyl group.

In the formula I, when R is^4-1Is hydroxy-substituted C₁～C₃When alkyl, said C₁～C₃The alkyl group may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or a methyl group.

In the formula I, R^4-1Preferably 2 or 3.

In formula I, X is preferably N.

In the cleaning solution, the mass fraction of the alkali can be 1-20%, preferably 5-15%, and the mass fraction is the mass percentage of the alkali in the total mass of the raw materials.

In the cleaning solution, the type of the base may be a compound of formula I, and is more preferably a compound of formula I

And more preferably

One or more of (a).

In the cleaning solution, the mass fraction of the alcohol amine can be 1-10%, preferably 5-8%, and the mass fraction is the mass percentage of the alcohol amine in the total mass of the raw materials.

The alcohol amine may be an alcohol amine conventionally used in the art, and is preferably one or more of monoethanolamine, diglycolamine, triethanolamine, isobutanolamine, and isopropanolamine.

In the cleaning solution, the mass fraction of the antioxidant can be 0.002-0.100%, preferably 0.005-0.010%, and the mass fraction is the mass percentage of the antioxidant enzyme in the total mass of the raw materials.

In the cleaning solution, the antioxidant may be a reducing agent and/or a reducing enzyme preparation, preferably a reducing enzyme preparation. The reducing agent may be ascorbic acid. The reductive enzyme preparation may be one or more of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), thioredoxin peroxidase, succinate dehydrogenase, sulfite reductase and nitrite reductase. The superoxide dismutase may be a superoxide dismutase conventional in the art, preferably copper and zinc containing superoxide dismutase (CUZNSOD).

In the cleaning solution, the mass fraction of the corrosion inhibitor can be 0.1-1.0%, preferably 0.5-0.8%, and the mass fraction is the mass percentage of the corrosion inhibitor in the total mass of the raw materials.

In the cleaning solution, the corrosion inhibitor can be a corrosion inhibitor conventional in the field, and is preferably one or more of 2-mercaptobenzothiazole, catechol, pyrogallol and 5-aminotetrazole.

In the cleaning solution, the mass fraction of the chelating agent can be 0.1-1.0%, preferably 0.3-0.9%, and the mass fraction is the mass percentage of the chelating agent in the total mass of the raw materials.

In the cleaning solution, the chelating agent may be a chelating agent conventional in the art, and is preferably one or more of malonic acid, maleic acid, arginine and ethylenediaminetetraacetic acid (EDTA).

In the cleaning solution, the mass fraction of the surfactant can be 0.1-1.0%, preferably 0.2-0.7%, and the mass fraction is the mass percentage of the surfactant in the total mass of the raw materials.

In the cleaning solution, the surfactant can be a surfactant conventional in the art, and preferably an ionic surfactant. The ionic surfactant is preferably an anionic surfactant.

Wherein, the anionic surfactant is preferably one or more of dodecyl benzene sulfonic acid, isooctyl alcohol sodium sulfate and phenol polyoxyethylene ether sodium sulfate.

In the cleaning solution, the water is preferably one or more of deionized water, pure water and ultrapure water.

In one embodiment of the present invention, the cleaning solution is prepared from the following raw materials: said base, said alcohol amine, said antioxidant, said corrosion inhibitor, said chelating agent, said surfactant, and said water.

The invention also provides a preparation method of the cleaning solution, which comprises the following steps: and mixing the raw materials to obtain the cleaning solution.

Wherein, the solid component in the raw material components is preferably added into the liquid component and stirred uniformly.

Wherein the temperature of the mixing may be room temperature.

The invention also provides application of the cleaning solution in cleaning a semiconductor device after chemical mechanical polishing.

Wherein the chemical mechanical polishing substrate is preferably one or more of a copper interconnection substrate, a cobalt interconnection substrate and a tungsten interconnection substrate

Wherein, the semiconductor device is preferably one or more of a copper-based chip, a cobalt-based chip and a tungsten-based chip.

The invention also provides an application of the alkali in chemical mechanical polishing and cleaning.

Wherein the chemical mechanical polishing substrate is preferably one or more of a copper interconnection substrate, a cobalt interconnection substrate and a tungsten interconnection substrate.

In the present invention, the "antioxidant" means a substance which acts against or scavenges radicals. The antioxidant is divided into antioxidant enzyme substances and small molecular compounds with antioxidant effect. The small molecule compound having an antioxidant effect may be a reducing agent, such as ascorbic acid.

In the present invention, "alkenyl group" includes straight and branched alkenyl groups, and the double bond may be at any position of the alkenyl group.

The above preferred conditions can be arbitrarily combined to obtain preferred embodiments of the present invention without departing from the common general knowledge in the art.

The reagents and starting materials used in the present invention are commercially available.

The positive progress effects of the invention are as follows: the cleaning solution avoids the use of TMAH, has low corrosion rate to copper, cobalt and tungsten, has good corrosion inhibition performance, and has the advantages of good stability, low toxicity, strong biocompatibility, good environmental protection performance and the like.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

The following table is the base used in the examples. The bases A19-A29 in the following examples are self-made, and tetramethylammonium chloride is used for replacing corresponding ammonium chloride according to the method in CN101680101B example 2 respectively to prepare the bases A19-A29.