Application of hydroxylamine compound cleaning fluid

Abstract

The invention discloses application of a hydroxylamine compound cleaning solution. In particular to application of a hydroxylamine compound cleaning solution in cleaning plasma etched and ashed wafers. The hydroxylamine compound cleaning solution is prepared from the following components in percentage by mass: 1 to 30 percent of a hydroxylamine compound, 1 to 5 percent of a corrosion inhibitor, 0.1 to 5 percent of a chelating agent, 0.01 to 5 percent of a nonionic surfactant and 1 to 50 percent of a water-soluble organic solvent and water. The sum of the mass fractions of the components is 100%. The hydroxylamine compound cleaning fluid is safe and environment-friendly, solves the problem of high cost caused by fixed raw material sources, reduces the cost, and is safe and reliable.

Description

Technical Field

[0001] The present invention relates to the application of a hydroxylamine compound cleaning solution. Background Art

[0002] In the development of semiconductor integrated circuits, large-scale, high-density, and miniaturization have become the development trends. In the manufacturing process, the coating, exposure, development, and etching of the photoresist layer are necessary process steps for the pattern manufacturing of components. At the end of patterning (i.e., after the coating, imaging, ion implantation, and dry etching of the photoresist layer), before the next process step, the residues of the photoresist layer material need to be completely removed. During dry etching or ion implantation, ion bombardment hardens the surface layer of the photoresist, forming a hard, carbonized outer shell that prevents the cleaning solution from cleaning the underlying main photoresist. Commonly used cleaning methods involve ashing processes with oxygen plasma to penetrate the hard outer shell and remove the photoresist.

[0003] The residues after aluminum process chip etching coexist with dielectric etching. With the upgrade of technology, different material types are applied in the aluminum process. Hydroxylamine can effectively remove etching residues without damaging the dielectric layer. Currently, the removal of aluminum process residues mainly relies on hydroxylamine cleaning solutions. However, due to the use of hydroxylamine, the source of the cleaning agent raw materials is fixed, and there is an explosion risk during the storage and use of hydroxylamine. Therefore, using hydroxylamine substitutes to develop water-based cleaning agents with lower cost, higher efficiency, and stronger compatibility is the direction of improvement and optimization in this field. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the existing problems that the source of the cleaning agent raw materials is fixed and there is an explosion risk during the storage and use of hydroxylamine. Therefore, the present invention provides the application of a hydroxylamine compound cleaning solution. When the hydroxylamine compound cleaning solution of the present invention is applied to clean the wafer after plasma etching ashing, compared with the traditional hydroxylamine cleaning solution, it meets one or more of the following effect advantages: lower cost, higher efficiency, and stronger compatibility.

[0005] The present invention provides the application of a hydroxylamine compound cleaning solution, and the application is to clean the wafer after plasma etching ashing; the hydroxylamine compound cleaning solution contains the following components in mass fractions: 1-30% of hydroxylamine compounds, 1-5% of resist, 0.1-5% of chelating agent, 0.01-5% of non-ionic surfactant, 1-50% of water-soluble organic solvent, and water; the sum of the mass fractions of each component is 100%, and the mass fraction is the percentage of the mass of each component in the total mass of each component.

[0006] In certain preferred embodiments of the present invention, certain components and mass fractions in the application of the hydroxylamine compound cleaning solution for cleaning wafers after plasma etching and ashing are defined as follows. Components and mass fractions not mentioned are the same as those described in any embodiment of the present invention (abbreviated as "in some embodiments").

[0007] In some embodiments, the hydroxylamine compound is selected from one or more of N-methylhydroxylamine, N-ethylhydroxylamine, and N,N-diethylhydroxylamine; preferably N-methylhydroxylamine and / or N,N-diethylhydroxylamine.

[0008] In some embodiments, the resist is selected from one or more of catechol, pyrogallol, alkyl gallate, and alkyl catechol; preferably catechol.

[0009] In some embodiments, the chelating agent is an organic acid, preferably selected from one or more of amino acids, ethylenediaminetetraacetic acid (EDTA), lactic acid, benzoic acid, glycolic acid, malonic acid, maleic acid, salicylic acid, glyceric acid, oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, phthalic acid, malic acid, methanesulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, tartaric acid, citric acid, citrulline, gallic acid, and gallnut acid; preferably ethylenediaminetetraacetic acid.

[0010] In some embodiments, the nonionic surfactant is an EO-PO polymer, preferably selected from one or more of EO-PO polymer L42, EO-PO polymer L43, and EO-PO polymer L44; preferably EO-PO polymer L42.

[0011] In some embodiments, the water-soluble organic solvent can be a conventional solvent in the art, preferably a sulfone solvent and / or an alcohol solvent, more preferably dimethyl sulfoxide and / or triethylene glycol.

[0012] In some embodiments, the water is selected from one or more of deionized water, distilled water, and ultrapure water, such as deionized water.

[0013] In some embodiments, the mass fraction of the hydroxylamine compound is preferably 1-30%, more preferably 2%-25%; for example, 5%, 10%, 15%, or 20%.

[0014] In some embodiments, the mass fraction of the resist is preferably 1-5%, more preferably 1%-4%; for example, 2%.

[0015] In some embodiments, the mass fraction of the chelating agent is preferably 0.1-5%, more preferably 0.1%-1%; for example, 0.5%.

[0016] In some embodiments, the mass fraction of the non-ionic surfactant is preferably 0.01 - 5%, more preferably 0.5% - 4%; for example, 1%.

[0017] In some embodiments, the mass fraction of the water-soluble organic solvent is preferably 1 - 50%, more preferably 10% - 40%; for example, 25%.

[0018] In some embodiments, the hydroxylamine compound cleaning solution comprises the following components in mass fractions: 5% - 20% of hydroxylamine compounds, 1.5% - 2.5% of resist, 0.2% - 0.8% of chelating agent, 0.5% - 1.5% of non-ionic surfactant, 20% - 30% of water-soluble organic solvent, and water; the sum of the mass fractions of each component is 100%;

[0019] The hydroxylamine compounds are N-methylhydroxylamine and / or N,N-diethylhydroxylamine;

[0020] The resist is catechol;

[0021] The chelating agent is ethylenediaminetetraacetic acid;

[0022] The non-ionic surfactant is EO-PO polymer L42;

[0023] The water-soluble organic solvent is dimethyl sulfoxide;

[0024] The water is deionized water.

[0025] In some embodiments, the hydroxylamine compound cleaning solution consists of the following components in mass fractions: the above-mentioned hydroxylamine compounds (including the types and mass fractions of hydroxylamine compounds), the above-mentioned resist (including the types and mass fractions of resist), the above-mentioned chelating agent (including the types and mass fractions of chelating agent), 0.01 - 5% of non-ionic surfactant (including the types and mass fractions of non-ionic surfactant), 0.01 - 5% of water-soluble organic solvent (including the types and mass fractions of water-soluble organic solvent), and 0.01 - 5% of water (including the types and mass fractions of water); the sum of the mass fractions of each component is 100%.

[0026] In some embodiments, the hydroxylamine compound cleaning solution consists of any of the following formulations:

[0027] (1): 5% of N-methylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide, and the balance of deionized water;

[0028] (2): 10% N-methylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0029] (3): 15% N-methylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0030] (4): 20% N-methylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0031] (5): 5% N,N-diethylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0032] (6): 10% N,N-diethylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0033] (7): 15% N,N-diethylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water;

[0034] (8): 20% N,N-diethylhydroxylamine, 2% catechol, 0.5% ethylenediaminetetraacetic acid, 1% EO-PO polymer L42, 25% dimethyl sulfoxide, and the balance deionized water.

[0035] The present invention also provides a hydroxylamine compound cleaning solution, and the components of the hydroxylamine compound cleaning solution are as described above.

[0036] The present invention also provides a preparation method of the hydroxylamine compound cleaning solution, and the preparation method includes the following steps: mixing the components as described above.

[0037] In some embodiments, in the preparation method, the mixing is preferably adding the solid components to the liquid components and stirring evenly.

[0038] In some embodiments, in the preparation method, the mixing temperature is preferably room temperature.

[0039] In some embodiments, in the preparation method, the stirring time is 12 - 48 hours, preferably 20 hours; the stirring temperature does not exceed 60°C, preferably 50°C.

[0040] In the present invention, room temperature refers to 10 - 30°C.

[0041] On the basis of conforming to common general knowledge in the art, the above preferred conditions can be combined arbitrarily to obtain various preferred examples of the present invention.

[0042] The reagents and raw materials used in the present invention are all commercially available.

[0043] The positive and progressive effects of the present invention are as follows: The cleaning agent is safe and environmentally friendly, solves the problem of high cost caused by the fixed source of raw materials, reduces the cost, and is safe and reliable. Detailed implementation manners

[0044] The present invention will be further illustrated below by way of examples, but the present invention is not limited to the scope of the described examples. For the experimental methods without specific conditions noted in the following examples, they are carried out according to conventional methods and conditions, or selected according to the product instructions.

[0045] Preparation of the cleaning solution:

[0046] Mix the raw material components of the cleaning solution according to the types and contents in the following table to prepare the cleaning solution.

[0047] The preparation method is carried out in the following manner: Mix all the raw material components evenly. Among them, the mixing method is to add the solid components to the liquid components, stir for 20 hours, at a stirring temperature of 50°C, and stir evenly.

[0048] In the following examples, where the specific operating temperature is not specified, it is carried out under room temperature conditions.

[0049] In the present invention, room temperature refers to 10 - 30°C.

[0050] Table 1 Types of raw material components of the cleaning solution

[0051]

[0052]

[0053] Table 2 Dosage of raw material components of the cleaning solution

[0054]

[0055] Table 3 Mass fractions of raw material components of the cleaning solution

[0056]

[0057] The "margin" in the table is, for each example, 100% minus the mass percentage of other components.

[0058] Testing method:

[0059] Test the etching rate of silicon wafers of metallic aluminum and non-metal (plasma-enhanced silicon dioxide (PETEOS)), and clean wafers after plasma etching and ashing of three different types.

[0060] I. Testing method for the metallic corrosion rate of the cleaning solution:

[0061] 1. Use a Napson four-point probe to test the initial resistance value (Rs1) of a 4×4 cm aluminum blank silicon wafer.

[0062] 2. Immerse the 4×4 cm aluminum blank silicon wafer in a solution that has been pre-heated to a set temperature of 70°C for 60 minutes.

[0063] 3. Take out the 4×4 cm aluminum blank silicon wafer, rinse it, dry it with high-purity nitrogen, and then use a Napson four-point probe to test the resistance value (Rs2) of the 4×4 cm aluminum blank silicon wafer.

[0064] 4. Input the above resistance value and immersion time into a suitable program to calculate its corrosion rate.

[0065] II. Testing method for the non-metallic corrosion rate of the cleaning solution:

[0066] 1. Use a Nanospec6100 thickness gauge to measure the thickness (T1) of a 4×4 cm PETEOS silicon wafer.

[0067] 2. Immerse the 4×4 cm PETEOS silicon wafer in a solution that has been pre-heated to a set temperature of 70°C for 60 minutes.

[0068] 3. Take out the 4×4 cm PETEOS silicon wafer, rinse it, dry it with high-purity nitrogen, and then use a Nanospec6100 thickness gauge to measure the thickness (T2) of the 4×4 cm PETEOS silicon wafer.

[0069] 4. Input the above thickness value and immersion time into a suitable program to calculate its corrosion rate.

[0070] III. Method for wafer cleaning

[0071] 1. Place the wafer to be cleaned into a solution that has been pre-heated to a set temperature.

[0072] 2. Immerse the wafer according to the principle that the metal wires are immersed for 20 minutes and the channels and metal pads are immersed for 30 minutes.

[0073] 3. After the soaking time is up, take out the wafer, rinse it, dry it with high-purity nitrogen, and send it for SEM testing.

[0074] In each effect example, when the metal corrosion rate is below 2 A / min, there is basically no corrosion; when it is 2 - 4 A / min, there is slight corrosion; when it is 4 - 15 A / min, there is medium corrosion; and when it is above 15 A / min, there is severe corrosion.

[0075] In each effect example, when the non-metal corrosion rate is below 0.5 A / min, there is basically no corrosion; when it is 0.5 - 4 A / min, there is slight corrosion; when it is 4 - 10 A / min, there is medium corrosion; and when it is above 10 A / min, there is severe corrosion.

[0076] Table 4 Effect Examples

[0077]

[0078]

[0079] It can be seen from the experimental results that the hydroxylamine compound cleaning solution of the present invention has good cleaning effects and is superior to the hydroxylamine-containing cleaning solution in terms of the corrosion of metals and non-metals.

Claims

1. Application of a hydroxylamine compound cleaning solution, characterized in that, The application is to clean wafers after plasma etching and ashing; The hydroxylamine compound cleaning solution contains the following components by mass fraction: 1-30% of hydroxylamine compounds, 1-5% of resist, 0.1-5% of chelating agent, 0.01-5% of non-ionic surfactant, 1-50% of water-soluble organic solvent and water; the sum of the mass fractions of each component is 100%.

2. The application of the hydroxylamine compound cleaning solution according to claim 1, wherein It satisfies one or more of the following conditions; (1) The hydroxylamine compound is selected from one or more of N-methylhydroxylamine, N-ethylhydroxylamine and N,N-diethylhydroxylamine; (2) The resist is selected from one or more of catechol, pyrogallol, alkyl gallate and alkyl catechol; (3) The chelating agent is an organic acid; (4) The non-ionic surfactant is an EO-PO polymer; (5) The water-soluble organic solvent is a sulfone solvent and / or an alcohol solvent; (6) The water is selected from one or more of deionized water, distilled water and ultrapure water.

3. The application of the hydroxylamine compound cleaning solution according to claim 2, wherein It satisfies one or more of the following conditions; (1) The hydroxylamine compound is N-methylhydroxylamine and / or N,N-diethylhydroxylamine; (2) The resist is catechol; (3) The chelating agent is one or more of amino acid, ethylenediaminetetraacetic acid, lactic acid, benzoic acid, glycolic acid, malonic acid, maleic acid, salicylic acid, glyceric acid, oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, phthalic acid, malic acid, methanesulfonic acid, ethanesulfonic acid, hydroxyethanesulfonic acid, tartaric acid, citric acid, citrulline, gallic acid and gallic acid; (4) The non-ionic surfactant is selected from one or more of EO-PO polymer L42, EO-PO polymer L43 and EO-PO polymer L44; (5) The water-soluble organic solvent is dimethyl sulfoxide and / or triethylene glycol; (6) The water is deionized water.

4. The application of the hydroxylamine compound cleaning solution according to claim 3, wherein, It satisfies one or two of the following conditions; (1) The chelating agent is ethylenediaminetetraacetic acid; (2) The non-ionic surfactant is EO-PO polymer L42.

5. The application of the hydroxylamine compound cleaning solution according to claim 1, characterized in that, It satisfies one or more of the following conditions; (1) The mass fraction of the hydroxylamine compound is 1-30%; (2) The mass fraction of the resist is 1-5%; (3) The mass fraction of the chelating agent is 0.1-5%; (4) The mass fraction of the non-ionic surfactant is 0.01-5%; (5) The mass fraction of the water-soluble organic solvent is 1-50%.

6. The application of the hydroxylamine compound cleaning solution according to claim 5, characterized in that, It satisfies one or more of the following conditions; (1) The mass fraction of the hydroxylamine compound is 2% to 25%; (2) The mass fraction of the resist is 1% to 4%; (3) The mass fraction of the chelating agent is 0.1% to 1%; (4) The mass fraction of the non-ionic surfactant is 0.5% to 4%; (5) The mass fraction of the water-soluble organic solvent is 10% to 40%.

7. Use of the hydroxylamine compound cleaning solution according to claim 6, characterized in that, It satisfies one or more of the following conditions; (1) The mass fraction of the hydroxylamine compound is 5%, 10%, 15% or 20%; (2) The mass fraction of the resist is 2%; (3) The mass fraction of the chelating agent is 0.5%; (4) The mass fraction of the non-ionic surfactant is 1%. (5) The mass fraction of the water-soluble organic solvent is 25%.

8. The application of the hydroxylamine compound cleaning solution according to claim 1, characterized in that, The hydroxylamine compound cleaning solution comprises the following components by mass fraction: 5%-20% of hydroxylamine compounds, 1.5%-2.5% of resist, 0.2%-0.8% of chelating agent, 0.5%-1.5% of non-ionic surfactant, 20%-30% of water-soluble organic solvent and water; the sum of the mass fractions of each component is 100%. The hydroxylamine compound is N-methylhydroxylamine and / or N,N-diethylhydroxylamine. The resist is catechol. The chelating agent is ethylenediaminetetraacetic acid. The non-ionic surfactant is EO-PO polymer L42. The water-soluble organic solvent is dimethyl sulfoxide. The water is deionized water.

9. Use of the hydroxylamine compound cleaning solution according to any one of claims 1-8, characterized in that, The hydroxylamine compound consists of the following components by mass fraction: the hydroxylamine compound as described in any one of claims 1-8, the resist as described in any one of claims 1-8, the chelating agent as described in any one of claims 1-8, the non-ionic surfactant as described in any one of claims 1-8, the water-soluble organic solvent as described in any one of claims 1-8 and the water as described in any one of claims 1-8; the sum of the mass fractions of each component is 100%.

10. The application of the hydroxylamine compound cleaning solution according to claim 1, wherein, The hydroxylamine compound cleaning solution consists of any one of the following components: (1): 5% of N-methylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (2): 10% of N-methylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (3): 15% of N-methylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (4): 20% of N-methylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (5): 5% of N,N-diethylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (6): 10% of N,N-diethylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (7): 15% of N,N-diethylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water. (8): 20% of N,N-diethylhydroxylamine, 2% of catechol, 0.5% of ethylenediaminetetraacetic acid, 1% of EO-PO polymer L42, 25% of dimethyl sulfoxide and the balance of deionized water.

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