Degumming liquid as well as preparation method and application thereof

Abstract

The invention provides a photoresist removing solution as well as a preparation method and application thereof, and belongs to the technical field of chip cleaning. The photoresist removing solution comprises the following raw materials in parts by mass: 10-25 parts of organic amine, 50-80 parts of an organic solvent, 0.3-1 part of a metal corrosion inhibitor, 0.5-2 parts of a metal complexing agent, 0.5-2 parts of a wetting agent and 1-3 parts of a dispersing agent, wherein the dispersing agent comprises polyether amine A or a polyethyleneimine alkoxy compound. The photoresist removing liquid prepared by adding the dispersing agent can thoroughly clean a chip, and the phenomenon of after-tack of photoresist is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of chip cleaning, and in particular to a degumming solution and a preparation method and application thereof. Background Art

[0002] Photolithography is a key step in chip manufacturing. After the mask pattern is copied and transferred to the chip, the photoresist as a sacrificial layer needs to be thoroughly cleaned by a degumming solution (photoresist stripping solution) for subsequent multiple photolithography processes. Conventional degumming solutions with alkanones, alcohol ethers, amides and organic bases as the main components can clean non-cross-linked photoresists; however, after high temperature or optical induction, and high-power laser / plasma etching, the photoresist is cross-linked, and the above degumming solution loses the ability to dissolve and strip, resulting in the problem of photoresist residue. This abnormality often occurs in the manufacturing process of power chips and flip chips, which will cause chip short circuits, reduce reliability and production yield, and needs to be thoroughly resolved.

[0003] Patent CN107085357 A uses hydroxyethylethylenediamine as a special organic amine, supplemented by a combination of organic fatty amines, organic alcohol amines, alcohol ether solvents, amide solvents, sulfone and alkane ketone solvents and corrosion inhibitors, and proposes a cleaning solution for deep hardened cross-linked photoresist residues. The patent emphasizes the effect of hydroxyethylethylenediamine as a degumming enhancement component to broaden the degumming window, but does not take into account the problem that the deeply hardened cross-linked photoresist cannot be dissolved, and the cross-linked photoresist dispersed in the degumming solution sticks back to the chip surface. Therefore, it is of great significance to study a degumming solution and its preparation method, and use it to clean cross-linked photoresist. Summary of the invention

[0004] The purpose of the present invention is to provide a degumming solution and a preparation method and application thereof, so as to solve the problem of cross-linked photoresist back-adhesion.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a degumming solution, which comprises the following raw materials in parts by mass: 10 to 25 parts of an organic amine, 50 to 80 parts of an organic solvent, 0.3 to 1 part of a metal corrosion inhibitor, 0.5 to 2 parts of a metal complexing agent, 0.5 to 2 parts of a wetting agent, and 1 to 3 parts of a dispersant; the dispersant is selected from polyetheramine A or a polyethyleneimine alkoxy compound.

[0007] Preferably, the organic amine is selected from one or more of monoethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol and N-methylethanolamine; the molecular weight of the polyetheramine A is 1000-4000; and the polyethyleneimine alkoxy compound is LUPASOL PN80.

[0008] Preferably, the organic solvent is selected from one or more of dimethyl sulfoxide, tetramethyl sulfoxide, sulfolane, N-methylpyrrolidone, N-ethylpyrrolidone, N-cyclohexylpyrrolidone, dimethylformamide, dimethylacetamide and diethylene glycol.

[0009] Preferably, the metal corrosion inhibitor is a compound of compound A and alkyl mercaptan, wherein compound A is selected from hydrazine hydrate, acetone oxime or carbohydrazide.

[0010] Preferably, the mass ratio of the compound A to the alkyl mercaptan is 1-2:1-2.

[0011] Preferably, the alkyl mercaptan is selected from hexadecyl mercaptan or octadecyl mercaptan.

[0012] Preferably, the metal complexing agent is selected from carboxyethyl thiosuccinic acid and / or ethylenediamine di-o-phenylacetic acid; and the wetting agent is selected from polyetheramine B or acetylenic alcohol.

[0013] Preferably, the molecular weight of the polyetheramine B is 500-800; and the acetylene alcohol is selected from C10 acetylene glycol or C12 acetylene glycol.

[0014] The present invention provides a method for preparing the above-mentioned degumming solution, comprising the following steps: mixing an organic amine, an organic solvent, a metal complexing agent, a wetting agent and a dispersant, introducing nitrogen, adding a metal corrosion inhibitor, mixing evenly, filtering, and obtaining the degumming solution.

[0015] The present invention provides an application of the above-mentioned degumming liquid in cleaning photoresist, comprising the step of placing a chip in the degumming liquid for immersion.

[0016] Beneficial effects of the present invention:

[0017] In the degumming solution of the present invention, the organic amine is used as the alkaline medium source, which can strip the photoresist on the chip surface and neutralize the acidic components containing carboxyl groups in the photoresist; the organic solvent can dissolve or swell the photoresist; the organic amine and the organic solvent are the main components of the degumming solution; the metal corrosion inhibitor can slow down or avoid the side reaction of the metal electrode on the chip surface during the degumming cleaning process, and maintain the intrinsic morphology and performance of the metal; the metal complexing agent is used as a cleaning anti-interference component, which searches and locks the metal ions in the degumming solution, avoids the metal ions from combining with the carboxyl components in the photoresist to reduce the neutralization and cleaning effect of the organic alkali, stabilizes the cleaning ability, and widens the process window; the wetting agent can quickly penetrate into the gap of the hardened cross-linked photoresist, wets the cross-linked material, and discharges the bubbles at the interface of the degumming solution and the cross-linked photoresist, so that the cross-linked photoresist is fully in contact with the degumming solution, improves the cleaning efficiency, and achieves the purpose of thorough stripping. The dispersant improves the dispersion stability of the stripped hardened cross-linked material in the degumming solution due to its unique branched structure, and avoids the hidden danger of back-adhesion to the chip.

[0018] The degumming liquid of the invention can clean the photoresist thoroughly without the photoresist sticking back. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a metallographic microscope image of a chip after being cleaned with the degumming solution of Example 1;

[0020] Figure 2 This is a metallographic microscope image of the chip after being cleaned with the degumming solution of Comparative Example 1;

[0021] Figure 3 This is a metallographic microscope image of the chip after being cleaned with the degumming solution of Comparative Example 2. DETAILED DESCRIPTION

[0022] The present invention provides a degumming solution, which comprises the following raw materials in parts by mass: 10 to 25 parts of an organic amine, 50 to 80 parts of an organic solvent, 0.3 to 1 part of a metal corrosion inhibitor, 0.5 to 2 parts of a metal complexing agent, 0.5 to 2 parts of a wetting agent, and 1 to 3 parts of a dispersant; the dispersant is selected from polyetheramine A or a polyethyleneimine alkoxy compound.

[0023] The present invention adopts a dispersant containing a branched chain structure to improve the dispersion stability of the peeled hardened cross-linked material in the degumming solution, thereby avoiding the hidden danger of back-adhesion to the chip.

[0024] In the present invention, the organic amine is selected from one or more of monoethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol and N-methylethanolamine; the molecular weight of the polyetheramine A is 1000-4000, preferably JEFFAMINET3000 or JEFFAMINE ED2003; and the polyethyleneimine alkoxy compound is LUPASOLPN80.

[0025] In the present invention, the organic solvent is selected from one or more of dimethyl sulfoxide, tetramethyl sulfoxide, sulfolane, N-methylpyrrolidone, N-ethylpyrrolidone, N-cyclohexylpyrrolidone, dimethylformamide, dimethylacetamide and diethylene glycol, preferably a mixed solvent.

[0026] In the present invention, the metal corrosion inhibitor is a compound of compound A and alkyl mercaptan, wherein compound A is selected from hydrazine hydrate, acetone oxime or carbohydrazide.

[0027] In the present invention, the mass ratio of the compound A to the alkyl mercaptan is 1-2:1-2, preferably 2:1, 1:1, 1:2.

[0028] In the present invention, the alkyl mercaptan is selected from hexadecyl mercaptan or octadecyl mercaptan.

[0029] In the present invention, the metal complexing agent is selected from carboxyethyl thiosuccinic acid and / or ethylenediamine di-o-phenylacetic acid; and the wetting agent comprises polyetheramine B or acetylenic alcohol.

[0030] In the present invention, the molecular weight of the polyetheramine B is 500-800, preferably JEFFAMINE ED600 or JEFFAMINE M600; the acetylene alcohol is selected from C10 acetylene glycol or C12 acetylene glycol.

[0031] The present invention provides a method for preparing the above-mentioned degumming solution, comprising the following steps: mixing an organic amine, an organic solvent, a metal complexing agent, a wetting agent and a dispersant, introducing nitrogen, adding a metal corrosion inhibitor, mixing evenly, filtering, and obtaining the degumming solution.

[0032] In the present invention, the purpose of introducing nitrogen is to discharge the air in the liquid and the stirring kettle; the filtration is performed with a precision of 0.3 microns.

[0033] The present invention provides an application of the above-mentioned degumming liquid in cleaning photoresist, comprising the step of placing a chip in the degumming liquid for immersion.

[0034] In the present invention, the temperature of the degumming solution is 80-90° C.; the soaking time is 10-20 minutes.

[0035] In the present invention, after the soaking is completed, the chip is preferably rinsed, washed, dehydrated and blown dry.

[0036] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0037] Example 1

[0038] At room temperature and pressure, in a cleanroom of Class 1000 or above, 15 parts of monoethanolamine, 55 parts of N-methylpyrrolidone, 25 parts of dimethylformamide, 2 parts of carboxyethyl thiosuccinic acid, 0.5 parts of 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 1 part of JEFFAMINE T3000 were placed in a stirring kettle and stirred evenly. Then, nitrogen was introduced into the mixed liquid in the stirring kettle to discharge and replace the air in the mixed liquid and the stirring kettle. Finally, 0.4 parts of carbohydrazide and 0.2 parts of octadecyl mercaptan were added, stirred evenly again, and after passing the test, filtered and packaged at a precision of 0.3 microns to obtain a degumming solution.

[0039] Example 2

[0040] At room temperature and pressure, in a cleanroom of Class 1000 or above, 25 parts of monoisopropanolamine, 30 parts of cyclopentane sulfone, 30 parts of diethylene glycol, 0.3 parts of carboxyethyl thiosuccinic acid, 0.6 parts of ethylenediamine di-o-phenylacetic acid, 0.5 parts of 2,5,8,11-dimethyl-6-dodecene-5,8-diol and 1.5 parts of JEFFAMINE ED2003 were placed in a stirring tank and stirred evenly, and then nitrogen was introduced into the mixed liquid in the stirring tank to discharge and replace the air in the mixed liquid and the stirring tank, and finally 0.5 parts of hydrazine hydrate and 0.5 parts of hexadecyl mercaptan were added, and stirred evenly again. After passing the test, the solution was filtered and packaged at a precision of 0.3 microns to obtain a degumming solution.

[0041] Example 3

[0042] At room temperature and pressure, in a cleanroom of Class 1000 or above, 10 parts of 2-amino-2-methyl-1-propanol, 25 parts of tetramethyl sulfoxide, 25 parts of dimethyl sulfoxide, 0.6 parts of carboxyethyl thiosuccinic acid, 0.3 parts of ethylenediamine di-o-phenylacetic acid, 2 parts of JEFFAMINE ED600, and 3 parts of LUPASOL PN80 were placed in a stirring tank and stirred evenly, and then nitrogen was introduced into the mixed liquid in the stirring tank to discharge and replace the air in the mixed liquid and the stirring tank, and finally 0.2 parts of acetone oxime and 0.4 parts of hexadecyl mercaptan were added, and stirred evenly again. After passing the test, the solution was filtered and packaged at a precision of 0.3 microns to obtain a degumming solution.

[0043] Example 4

[0044] At room temperature and pressure, in a cleanroom of Class 1000 or above, 20 parts of N-methylethanolamine, 40 parts of N-ethylpyrrolidone, 30 parts of N-cyclohexylpyrrolidone, 0.5 parts of ethylenediaminedi-o-phenylacetic acid, 1 part of JEFFAMINE M600 and 2 parts of JEFFAMINE ED2003 were placed in a stirring tank and stirred evenly, and then nitrogen was introduced into the mixed liquid in the stirring tank to discharge and replace the air in the mixed liquid and the stirring tank, and finally 0.3 parts of acetone oxime and 0.3 parts of octadecyl mercaptan were added, and stirred evenly again. After passing the test, the solution was filtered and packaged at a precision of 0.3 microns to obtain a degumming solution.

[0045] Comparative Example 1

[0046] At normal temperature and pressure, in a cleanroom of Class 1000 or above, 15 parts of monoethanolamine, 55 parts of N-methylpyrrolidone and 25 parts of dimethylformamide are placed in a stirring kettle and stirred evenly. Then nitrogen is introduced into the mixed liquid in the stirring kettle to discharge and replace the air in the mixed liquid and the stirring kettle. After passing the test, it is filtered and packaged at a precision of 0.3 microns to obtain a degumming liquid.

[0047] Comparative Example 2

[0048] At room temperature and pressure, in a cleanroom of Class 1000 or above, 15 parts of monoethanolamine, 55 parts of N-methylpyrrolidone, 25 parts of dimethylformamide, 2 parts of carboxyethyl thiosuccinic acid, and 0.5 parts of 2,4,7,9-tetramethyl-5-decyne-4,7-diol were placed in a stirring kettle and stirred evenly. Then, nitrogen was introduced into the mixed liquid in the stirring kettle to discharge and replace the air in the mixed liquid and the stirring kettle. Finally, 0.4 parts of carbohydrazide and 0.2 parts of octadecyl mercaptan were added, and the mixture was stirred evenly again. After passing the test, the mixture was filtered and packaged at a precision of 0.3 microns to obtain a degumming solution.

[0049] The positive photoresist is removed by using the stripping solution of Examples 1 to 4, Comparative Example 1 or Comparative Example 2. The specific operation process is as follows: the chip coated with positive photoresist and etched by high-power plasma is immersed in the stripping solution at 85° C. for 15 minutes, soaked and rinsed in a room temperature acetone solution (concentration higher than 99%) for 30 seconds, rinsed in a pure water tank, dehydrated with room temperature isopropanol, and blown dry with hot nitrogen at 70° C.

[0050] The surface of the cleaned chip was observed using a metallographic microscope to identify the cleaning ability of the degumming solution. The results showed that the degumming solutions of Examples 1 to 4 were able to thoroughly clean the chip coated with positive photoresist and etched by high-power plasma without photoresist sticking back.

[0051] Figures 1 to 3 This is a metallographic microscope image of the chip after cleaning. Figure 1 It shows that the degumming solution of Example 1 can thoroughly clean the chip coated with positive photoresist and etched by high-power plasma without photoresist sticking back; Figure 2 It shows that the photoresist on the chip surface after cleaning with the degumming solution of Comparative Example 1 is residual, and the cross-linking glue is not cleaned thoroughly; Figure 3 It shows that the degumming solution of comparative example 2 is not cleaned thoroughly, and the photoresist has a re-sticking phenomenon;

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A degumming solution, characterized in that: The degumming solution comprises the following raw materials in parts by weight: 10 to 25 parts of organic amine, 50 to 80 parts of organic solvent, 0.3 to 1 part of metal corrosion inhibitor, 0.5 to 2 parts of metal complexing agent, 0.5 to 2 parts of wetting agent, and 1 to 3 parts of dispersant; the dispersant is selected from polyetheramine A or polyethyleneimine alkoxy compound.

2. The degumming solution according to claim 1, characterized in that: The organic amine is selected from one or more of monoethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol and N-methylethanolamine; the molecular weight of the polyetheramine A is 1000-4000; and the polyethyleneimine alkoxy compound is LUPASOL PN80.

3. The degumming solution according to claim 1 or 2, characterized in that: The organic solvent is selected from one or more of dimethyl sulfoxide, tetramethyl sulfoxide, sulfolane, N-methylpyrrolidone, N-ethylpyrrolidone, N-cyclohexylpyrrolidone, dimethylformamide, dimethylacetamide and diethylene glycol.

4. The degumming solution according to claim 3, characterized in that: The metal corrosion inhibitor is a compound of compound A and alkyl mercaptan, wherein compound A is selected from hydrazine hydrate, acetone oxime or carbohydrazide.

5. The degumming solution according to claim 4, characterized in that: The mass ratio of the compound A to the alkyl mercaptan is 1-2:1-2.

6. The degumming solution according to claim 4 or 5, characterized in that: The alkyl mercaptan is selected from hexadecyl mercaptan or octadecyl mercaptan.

7. The degumming solution according to claim 6, characterized in that: The metal complexing agent is selected from carboxyethyl thiosuccinic acid and / or ethylenediamine di-o-phenylacetic acid; and the wetting agent is selected from polyetheramine B or acetylenic alcohol.

8. The degumming solution according to claim 7, characterized in that: The molecular weight of the polyetheramine B is 500-800; the acetylene alcohol is selected from C10 acetylene glycol or C12 acetylene glycol.

9. The method for preparing the degumming solution according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: mixing organic amine, organic solvent, metal complexing agent, wetting agent and dispersant, introducing nitrogen, adding metal corrosion inhibitor, mixing evenly, filtering and obtaining degumming solution.

10. Use of the degumming solution according to any one of claims 1 to 8 in cleaning photoresist, characterized in that: The method comprises the steps of placing the chip in a degumming solution for immersion.

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