WO2023103853A1

WO2023103853A1 - Cleaning fluid and use thereof

Info

Publication number: WO2023103853A1
Application number: PCT/CN2022/135392
Authority: WO
Inventors: 肖林成; 刘兵; 赵鹏
Original assignee: 安集微电子科技（上海）股份有限公司
Priority date: 2021-12-09
Filing date: 2022-11-30
Publication date: 2023-06-15
Also published as: CN116254159A; TW202323513A

Abstract

The present invention provides a cleaning fluid, comprising: an oxidizing agent, a cobalt corrosion inhibitor, water, and a compound of structural formula (1): , where R1, R2 and R3 represent a hydrogen atom or a substituent. The cleaning fluid in the present invention can effectively reduce the residues of organic matters on the surface of cobalt, and can effectively remove a titanium nitride hard mask and the etching residues of a photoresist by means of cooperation with an oxidizing agent, a cobalt corrosion inhibitor, water, etc. Moreover, the cleaning fluid exibits a small corrosion rate on metal materials, non-metal materials, low-k dielectric materials, etc. during cleaning with a high-speed rotating single-chip microcomputer, such that the electrical performance of a semiconductor device is improved, the product yield is also greatly improved, and the operation window is large. The cleaning fluid has good application prospects in the field of the cleaning of high-end semiconductors such as integrated circuits fabricated at 14 nm and more advanced nodes.

Description

A kind of cleaning solution and its application

technical field

The invention relates to the field of chemical cleaning liquid, in particular to a cleaning liquid and its application.

Background technique

Photoresist hardmasks are commonly used to pattern semiconductor materials or dielectrics, and are currently used in dual damascene processes to form interconnects in back-end metallization of microelectronic devices. As the size becomes smaller and smaller, the reliability of the integrated circuit (IC) is more and more concerned by the IC manufacturing technology. Tracking the impact of interconnect failure mechanisms on device performance and reliability requires more from integration schemes, interconnect materials, and processes, requiring optimal Low-k dielectric materials and their associated deposition, patterning, etching, and cleaning to A dual damascene interconnect pattern is formed. The hardmask scheme approach to interconnect patterning wafer fabrication is capable of transferring the pattern to the bottom layer with the tightest optimal dimensional control.

With the development of technology nodes to 14nm, 7nm or even smaller line widths and increased aspect ratios, metal hard mask materials such as TiN are used to achieve better etch/removal selectivity and better pattern retention during pattern etching and profile control for Low-k materials. It is necessary to modify or even completely remove the TiN hard mask. At the same time, it has good compatibility with metal materials such as copper, cobalt, tantalum, and rubidium, and Low-k dielectric materials such as TEOS and BDII. In addition, due to the low surface energy and cross-linking properties of etching residues, as well as changes in the physical and chemical properties of the residue components, coupled with compatibility issues between cleaning solutions and device membrane materials and structures, the development of effective photoresist removal Etching residues while protecting Low-k dielectric materials and non-metallic materials, and cleaning solutions with low residues on the surface of metal materials are becoming more and more challenging.

The reports on high-end semiconductor cleaning fluid at home and abroad are mainly from European and American countries. US Patent US10920141B2 discloses a composition and method for selectively etching titanium nitride to protect cobalt. The cleaning solution mainly uses hydrogen peroxide as the oxidant, TMAH and fluorine-containing components as the etchant, adding azoles and cationic quaternary salts as corrosion inhibitors, organic acids as chelating agents, and solvent water to selectively remove titanium nitride and photoinduced corrosion. Resist etch residue. According to the published patents, the cleaning solution can work at a pH value of 5-12 and a temperature range of 20°C to 100°C, and the TiN etching rate tested at 50°C is greater than

Cu etch rate is less than

Co etch rate is less than

SiN etch rate less than

The etch rate of Low-k dielectric material is less than

The company's products are mainly used in European and American countries, and still occupy a large market share in the field of semiconductor cleaning fluid.

In the latest report, Versum Material Company of the United States discloses a composition, method and system for removing TiN hard masks from electronic circuit devices in patent US11017995B2. The pH value range of the composition is 5.5-14, the working temperature is 35°C-70°C, and has a wide application range, and can be used in semiconductor substrates or wafers, flat panel displays, phase change memories, solar panels, microelectronics, integrated circuits Or computer chips and other fields. The cleaning solution mainly uses hydrogen peroxide as oxidant, macromolecular organic acid as hydrogen peroxide stabilizer, azoles and polyols as metal corrosion inhibitors, quaternary ammonium hydroxide and ammonium salt as etchant, water as solvent, and optional Fluoride is used to enhance the cleaning ability, selectively remove titanium nitride and residues from the plasma etching process, and at the same time effectively protect the second materials such as Cu, Co, and Low-k dielectric materials.

In order to ensure better wafer surface treatment, in the IC field of 14nm and below technology nodes, it is often used to configure hydrogen peroxide and use the "To drain" mode to clean the patterned wafer. BASF of Germany discloses a recyclable cleaning solution composition in patent CN110713868A, which is mainly composed of agent A and agent B H2O2 in a volume ratio of 1:1, and adopts the "Recycle" mode to adjust Cu, Co, Etching rates of Ru and TiN. Wherein the agent A composition includes organic amine 4-methylmorpholine 4-oxide, polyethyleneimine+azoles as a corrosion inhibitor, TMAH+ammonium dihydrogen phosphate as a buffer, organic acid ammonium salt as an etchant, ethylenediamine Alcohol ethers, as organic solvents, optional aprotic solvents and water, have good cleaning performance on fluorocarbon (CFx) polymers and organic residues, can completely or partially remove TiN, and simultaneously protect metal materials such as Cu, Co, Ru, etc., the The products are currently mainly used in the processing of semiconductor wafers in Taiwan Semiconductor Manufacturing Co., Ltd.

Contents of the invention

Therefore, the main purpose of the present invention is to provide a cleaning solution that can selectively remove the TiN hard mask, and can effectively reduce the organic matter on the surface of metal cobalt under the premise of protecting metal materials, non-metal materials and Low-k dielectric materials. residue.

Specifically, the present invention provides a chemical cleaning solution, comprising: oxidizing agent, cobalt corrosion inhibitor, water and a first compound, wherein the first compound has structural formula (1):

Wherein, R ₁ , R ₂ and R ₃ represent a hydrogen atom or a substituent.

Preferably, the first compound is selected from 1,2,4-triazole-3-carboxylic acid, 1,2,4-triazole-3-carboxylic acid methyl ester, 1,2,4-triazole Azole-3-carboxylic acid ethyl ester, 5-amino-1,2,4-triazole-3-carboxylic acid, 5-amino-1H--1,2,4-triazole-3-carboxylic acid methyl Ester, 5-amino-1H-1,2,4-triazole-3-carboxylic acid ethyl ester, 2,3,5-tri-O-triacetyl-B-D-ribofuranosyl-1,2,4- Triazole-3-carboxylic acid methyl ester (ribavirin condensate), 5-amino-1H-1,2,4-triazole-3-carboxylic acid amide, N-(2',4'- Dichlorobenzylidene)-5-amino-1H-1,2,4-triazole-3-carboxylic acid, 5-X-1H-1,2,4-triazole-3-carboxylic acid ethyl One or more of ester (X=Cl, Br, I), 5-methyl-2H-1,2,4-triazole-3-carboxylic acid.

Preferably, the mass percentage content of the first compound is 0.01wt%-10wt%.

Preferably, the oxidizing agent is selected from H ₂ O ₂ , N-methylmorpholine oxide, benzoyl peroxide, peracetic acid, urea peroxide, nitric acid, peracetic acid, peroxybenzoic acid, and alloxan One or more of; more preferably, the oxidizing agent is H ₂ O ₂ .

Preferably, the mass percent content of the oxidizing agent is 0.1wt%-30wt%.

Preferably, the cobalt corrosion inhibitor is a nitrogen-containing heterocyclic azole compound.

Preferably, the cobalt corrosion inhibitor is selected from benzotriazole (BTA), 1,2,4-triazole, 5-methylbenzotriazole (TTA), hydroxybenzotriazole, pyr Azole, tolutriazole, 3,5-dimethylpyrazole, tetrazole, 4-amino-1,2,4-triazole, benzothiazole, methyl-1H-benzotriazole (TTL), 2-aminobenzothiazole, 2-mercaptobenzothiazole, 3-amino-5-hydroxypyrazole, 1-phenylpyrazole, mercaptobenzimidazole, 5-aminotetrazole, 3-mercapto-1,2, 4-triazole, 3-isopropyl-1,2,4-triazole, 2-(5-amino-pentyl)-benzotriazole, 5-benzenethiol-benzotriazole, methyl tetra Azole, 5-phenyl-benzotriazole, 5-nitro-benzotriazole, 3-amino-5-mercapto-1,2,4-triazole, 1-amino-1,2,4-triazole , one or more of 1-amino-1,2,3-benzotriazole and thiazole; more preferably, the cobalt corrosion inhibitor is benzotriazole.

Preferably, the mass percent content of the cobalt corrosion inhibitor is 0.01wt%-10wt%.

Preferably, a chelating agent is also included, and the chelating agent is an organic acid.

Preferably, the chelating agent is selected from glycine, serine, proline, leucine, alanine, aspartic acid, asparagine, glutamine, valine, lysine, cystine , ethylenediaminetetraacetic acid (EDTA), trans-1,2 cyclohexanediaminetetraacetic acid (CDTA), uric acid, picolinic acid, nitrilotriacetic acid (NTA), ethylenediamine-N,N'-di Succinic Acid (EDDS), Glutamic Acid, Diethylenetriaminepentaacetic Acid (DTPA), Hydroxyethylethylenediaminetriacetic Acid (HEDTA), Iminodiacetic Acid (IDA), Nitrilotriacetic Acid, Salicylic Acid, Glucose acid, niacin, tartaric acid, citric acid, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), ethylene glycol tetraacetic acid (EGTA), 1 , 2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid) (HDDHA), propylene glycol One or more of amine tetraacetic acid.

Preferably, the mass percentage content of the chelating agent is 0.05-1000 ppm; more preferably, the mass percentage content of the chelating agent is 0.1-100 ppm.

Preferably, an organic base is further included, one or more selected from quaternary amine hydroxides, organic amines, and organic alcohol amines; more preferably, an organic base with a low metal ion content (<50 ppb).

Preferably, the quaternary ammonium hydroxide is selected from tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), trimethylphenylammonium hydroxide (TMPAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), benzyltrimethylammonium hydroxide (BTMAH), benzyltriethylammonium hydroxide (BTEAH), choline hydroxide, ammonium hydroxide, lauryl One or more of trimethylammonium hydroxide (DTAH), cetyltrimethylammonium hydroxide (CTOH);

The organic amine is selected from monoethylamine, diethylamine, triethylamine, tripropylamine, N'N-diethylethylenediamine, hydroxyethylethylenediamine, cyclohexylamine, 1,2-propylenediamine , one or more of pentamethyldiethylenetriamine;

The organic alcohol amine is selected from one or more of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), isopropanolamine, N-methylethanolamine .

Preferably, the mass percent content of the organic base is 0.1wt%-10wt%.

Preferably, ammonium salts of organic acids are further included.

Preferably, the organic acid ammonium salt is selected from ammonium formate, ammonium oxalate, ammonium lactate, ammonium tartrate, triammonium citrate, ammonium acetate, ammonium carbamate, ammonium carbonate, ammonium benzoate, tetraammonium EDTA, triammonium EDTA, One or more of diammonium EDTA, ammonium succinate, ammonium 1-H-pyrazole-3-carboxylate, ammonium malonate, ammonium adipate, and ammonium iminodiacetate.

Preferably, the mass percentage content of the organic acid ammonium salt is 0.01wt%-50wt%.

Another aspect of the present invention provides an application method of using any of the chemical cleaning solutions described above for cleaning cobalt.

Preferably, the applied temperature is 20-80°C; the applied pH value is 4-12

By adding a triazole compound, the residue of organic matter on the cobalt surface can be effectively reduced, and the combination of oxidizing agent, cobalt corrosion inhibitor, water, etc. can effectively remove the titanium nitride hard mask and photoresist etching residue, and at high speed In the cleaning of rotary single-chip microcomputer, the corrosion rate of metal materials, non-metal materials and Low-k dielectric materials is relatively small, the electrical performance of semiconductor devices is improved, the product yield rate is also greatly improved, and the operating window is large. High-end semiconductor cleaning fields such as integrated circuit 14nm and below technology nodes have good application prospects.

Description of drawings

Fig. 1 is the XPS spectrum of the cobalt surface after the cleaning solution of Example 21 of the present invention and Comparative Example 1;

Fig. 2 is the XPS spectrum of the cobalt surface after the cleaning solution of Example 22 of the present invention and Comparative Example 2;

Fig. 3 is the XPS spectrum of the cobalt surface after cleaning with the cleaning solutions of Example 23 and Comparative Example 3 of the present invention.

Detailed ways

The advantages of the present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

The cleaning solutions of Examples 1-30 and Comparative Examples 1-3 were prepared according to the components in Table 1 and their contents. And use it at the corresponding temperature.

Components and contents of the cleaning solution in Table 1 Examples 1-30 and Comparative Examples 1-3

In order to further test the polishing performance of the above-mentioned cleaning solutions, different materials were etched using the cleaning solutions of Examples 21-23. The specific test conditions are as follows:

Test objects and their sources for testing etch rate:

TiN (Titanium Nitride) Blank Wafer——Ramco Specialties Inc.

Cu (Copper) Blank Wafers - Ramco Specialties Inc.

Co (Cobalt) Blank Wafers - Ramco Specialties Inc.

SiON (Silicon Oxynitride) Blank Wafer - Ramco Specialties Inc.

TEOS (Silicon Dioxide) Blank Wafers - Ramco Specialties Inc.

BDII (Low Dielectric Constant Silicon Oxide) Blank Wafer - Ramco Specialties Inc.

Test method of etching rate of TiN, Cu, Co and other metals:

(1) Use the Napson four-point probe instrument to test the initial resistance value (Rs1) of a 5*5cm metal blank chip (TiN blank chip, Cu blank chip, Co blank chip);

(2) Put the 5*5cm metal blank wafer on the mini-SCM mini-SWT at 400rpm, treat the TiN blank wafer with cleaning solution for 5min, and chemically treat the Cu blank wafer and Co blank wafer for 10min;

(3) Take out the 5*5cm metal blank wafer, clean it with deionized water (DIW), dry it with high-purity nitrogen, and test the resistance value (Rs2) of the 5*5cm metal blank wafer with a Napson four-point probe instrument;

(4) Input the above resistance value and etching time into an appropriate program to calculate the etching rate of the metal.

Non-metal etching rate test methods such as SiON, TEOS, BDII:

1) Turn on the Nanospec6100 thickness gauge according to the standard, select the appropriate test program, put a 5*5cm non-metallic blank wafer (SiON blank wafer, TEOS blank wafer, BDII blank wafer) into the Nanospec6100 thickness gauge to test the thickness of the non-metallic blank wafer , rotate the non-metallic blank wafer 90° to continue the test, test 4 times continuously, and record the value;

2) If the non-metallic blank wafer is BDII, rinse it with water, treat it in a muffle furnace at 350°C for 20 minutes, cool it to room temperature in a desiccator, and then test the previous value; (other wafers do not need to step 2)

3) Put the 5*5cm non-metallic blank wafer on the mini-SWT at 400rpm, and treat it with cleaning solution for 10min;

4) Take out the 5*5cm non-metallic blank wafer, clean it with DIW, dry it with high-purity nitrogen, test the thickness of the wafer on the Nanospec6100 thickness gauge according to procedure 1, and record the value;

5) If the non-metallic blank wafer is BDII, rinse it with water, treat it in a muffle furnace at 350°C for 20 minutes, cool it to room temperature in a desiccator, and then test the value; (other wafers do not need to step 5)

6) Enter the above-mentioned before and after thickness values and etching time into a suitable program, and the etching rate is calculated as the thickness change divided by the chemical treatment time.

The etch rates of different blank wafers were tested according to the above-mentioned etch rate test method. Since cobalt corrosion inhibitors are basically heterocyclic compounds containing N, the adsorption of metal corrosion inhibitors in the cleaning solution on the cobalt surface was tested by X-ray photoelectron spectroscopy (XPS), and the signal intensity based on N element is shown in the figure 1 to Figure 3. At the same time, under the conditions of 50°C and 400rpm/min, the mini-SWT single-chip microcomputer was used to clean the patterned wafer for 90s, rinsed with water, dried with nitrogen, and observed and evaluated the wafer cleaning effect by SEM. The etching rates, surface adsorption results and cleaning effects of different blank wafers are shown in Table 2.

Table 2 Etching test and cleaning results of Examples 21-23 and Comparative Examples 1-3

金属钴表面吸附结果(XPS)Surface adsorption results of metal cobalt (XPS)	晶圆清洗结果Wafer Cleaning Results
◎基本无吸附◎Basically no adsorption	◎基本清洗干净◎Basic cleaning
○轻微吸附○Slight adsorption	○少量残留物○ A small amount of residue
△较多吸附△ More adsorption	△较多残留物△More residues
×严重吸附× Severe adsorption	×大量残留物×Large amount of residue

As can be seen from Table 2: under the situation that TiN hardmask is completely removed, the cleaning solution of the present invention is substantially basic to metal materials (such as Cu and Co) and non-metal materials (SiON, TEOS, BDII) used in the semiconductor manufacturing process. There is no etching, and its corrosion conditions meet the requirements of the semiconductor industry for cleaning single-chip microcomputers that are usually rotated at high speeds.

Comparison between Example 1 and Example 21 shows that the addition of 1,2,4-triazole-3-carboxylic acid has little change in the etching rate of the wafer, and both meet the etching requirements. Combining with Figure 1, it can be seen that the relative intensity of N elements on the cobalt surface treated with the cleaning solution of 1,2,4-triazole-3-carboxylic acid is weaker, indicating that the adsorption amount of organic matter on the surface of metal cobalt in Example 21 is higher than that without adding The comparative example 1 of the 1,2,4-triazole-3-carboxylic acid system is much less, and thus the organic residues on the cobalt surface are less. It can also be seen from the cleaning effect of the patterned wafers in Table 2 that the patterned wafers processed with the system of 1,2,4-triazole-3-carboxylic acid are basically cleaned, which is conducive to improving the quality of semiconductor devices. Rate.

Comparative Example 2 and Example 22 show that, with the addition of 1,2,4-triazole-3-carboxylate methyl ester system, the wafer etching rate processed is basically the same as that of the system without adding this component, Has not changed much. Combined with the X-ray photoelectron spectrometer analysis results shown in Figure 2, it can be seen that the relative intensity of N elements on the cobalt surface treated in Example 22 of the system with the addition of 1,2,4-triazole-3-carboxylate methyl ester is weaker, and the organic matter The adsorption amount on the cobalt surface is lower than that of the system without addition 2, the damascene metal channel cleaning effect of the patterned wafer is better, and the organic residue on the cobalt surface is further improved.

Comparison between Example 3 and Example 23 shows that there is little change in the etching rate of the wafer with or without the addition of 5-amino-1,2,4-triazole-3-carboxylic acid. From the analysis of the results of the X-ray photoelectron spectrometer in Figure 3, it can be seen that the corresponding intensity of the N element on the surface of metal cobalt treated with the addition of 5-amino-1,2,4-triazole-3-carboxylic acid system is weaker , indicating that the adsorption of organic matter is less, which is conducive to improving the conductivity of the patterned wafer.

Heterocyclic compounds containing N-azoles are very good protective agents for metal cobalt, and their adsorption on the surface of metal cobalt can effectively control the corrosion of cobalt, but the organic protective film also affects the conductivity of semiconductor devices. The XPS results show that the response intensity of the absorption peak of N element can reflect the adsorption degree of organic protective film on the surface of metal cobalt. There are active anions in the triazole compound, which form competitive adsorption with cobalt corrosion inhibitors on the surface of metal cobalt, which makes the metal corrosion inhibition. The agent can desorb from the cobalt surface in a short time while protecting the cobalt, further reducing the residue of organic matter on the surface of the metal cobalt.

In summary, the positive and progressive effect of the present invention lies in: by adding the first compound, the residue of organic matter on the cobalt surface can be effectively reduced. Cooperating with oxidant, cobalt corrosion inhibitor, water, etc., can effectively remove titanium nitride hard mask and photoresist etching residues, and clean metal materials, non-metal materials and Low-k dielectrics in high-speed rotary single-chip cleaning Electrical materials, etc. show a small corrosion rate, which improves the electrical performance of semiconductor devices, and the product yield rate has also been greatly improved. The operating window is large, and it has good applications in high-end semiconductor cleaning fields such as integrated circuit 14nm and below technology nodes. prospect.

It should be noted that the embodiments of the present invention have better implementability and are not intended to limit the present invention in any form. Any person skilled in the art may use the technical content disclosed above to change or modify equivalent effective embodiments However, any modifications or equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the scope of the technical solution of the present invention.

Claims

A cleaning solution, characterized in that it comprises:

An oxidizing agent, a cobalt corrosion inhibitor, water, and a first compound having the formula (1):

Wherein, R 1 , R 2 and R 3 represent a hydrogen atom or a substituent.
cleaning solution as claimed in claim 1, is characterized in that,

The first compound is selected from 1,2,4-triazole-3-carboxylic acid, 1,2,4-triazole-3-carboxylic acid methyl ester, 1,2,4-triazole-3 -ethyl carboxylate, 5-amino-1,2,4-triazole-3-carboxylic acid, 5-amino-1H--methyl 1,2,4-triazole-3-carboxylate, 5 -Amino-1H-1,2,4-triazole-3-carboxylic acid ethyl ester, 2,3,5-tri-O-triacetyl-B-D-ribofuranosyl-1,2,4-triazole -3-Carboxylic acid methyl ester (ribavirin condensate), 5-amino-1H-1,2,4-triazole-3-carboxylic acid amide, N-(2',4'-dichlorobenzene Methylene)-5-amino-1H-1,2,4-triazole-3-carboxylic acid, ethyl 5-X-1H-1,2,4-triazole-3-carboxylate (X One or more of =Cl, Br, I), 5-methyl-2H-1,2,4-triazole-3-carboxylic acid.
cleaning solution as claimed in claim 1, is characterized in that,

The mass percent content of the first compound is 0.01wt%-10wt%.
cleaning solution as claimed in claim 1, is characterized in that,

The oxidizing agent is selected from H 2 O 2 , N-methylmorpholine oxide, benzoyl peroxide, peracetic acid, urea peroxide, nitric acid, peracetic acid, peroxybenzoic acid, and alloxan or more.
cleaning solution as claimed in claim 1, is characterized in that,

The mass percent content of the oxidizing agent is 0.1wt%-30wt%
cleaning solution as claimed in claim 1, is characterized in that,

The cobalt corrosion inhibitor is a nitrogen-containing heterocyclic azole compound.
cleaning solution as claimed in claim 6, is characterized in that,

The cobalt corrosion inhibitor is selected from benzotriazole (BTA), 1,2,4-triazole, 5-methylbenzotriazole (TTA), hydroxybenzotriazole, pyrazole, toluene Triazole, 3,5-dimethylpyrazole, tetrazole, 4-amino-1,2,4-triazole, benzothiazole, methyl-1H-benzotriazole (TTL), 2-amino Benzothiazole, 2-mercaptobenzothiazole, 3-amino-5-hydroxypyrazole, 1-phenylpyrazole, mercaptobenzimidazole, 5-aminotetrazole, 3-mercapto-1,2,4-tri Azole, 3-isopropyl-1,2,4-triazole, 2-(5-amino-pentyl)-benzotriazole, 5-benzenethiol-benzotriazole, methyltetrazole, 5 -Phenyl-benzotriazole, 5-nitro-benzotriazole, 3-amino-5-mercapto-1,2,4-triazole, 1-amino-1,2,4-triazole, 1- One or more of amino-1,2,3-benzotriazole and thiazole.
cleaning solution as claimed in claim 1, is characterized in that,

The mass percent content of the cobalt corrosion inhibitor is 0.01wt%-10wt%.
cleaning solution as claimed in claim 1, is characterized in that,

Also included are chelating agents which are organic acids.
cleaning solution as claimed in claim 9, is characterized in that,

The chelating agent is selected from glycine, serine, proline, leucine, alanine, aspartic acid, asparagine, glutamine, valine, lysine, cystine, ethylene glycol Aminotetraacetic acid (EDTA), trans-1,2cyclohexanediaminetetraacetic acid (CDTA), uric acid, picolinic acid, nitrilotriacetic acid (NTA), ethylenediamine-N,N'-disuccinic acid (EDDS), glutamic acid, diethylenetriaminepentaacetic acid (DTPA), hydroxyethylethylenediaminetriacetic acid (HEDTA), iminodiacetic acid (IDA), nitrilotriacetic acid, salicylic acid, gluconic acid, tobacco acid, tartaric acid, citric acid, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), ethylene glycol tetraacetic acid (EGTA), 1,2- Bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, Ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid) (HDDHA), Propylenediaminetetraacetic acid one or more of.
cleaning solution as claimed in claim 9, is characterized in that,

The mass percent content of the chelating agent is 0.05-1000ppm.
cleaning solution as claimed in claim 1, is characterized in that,

It further includes an organic base, selected from one or more of quaternary amine hydroxides, organic amines, and organic alcohol amines.
The cleaning solution according to claim 12, characterized in that,

The quaternary ammonium hydroxide is selected from tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), trimethylphenylammonium hydroxide (TMPAH), tetrapropylammonium hydroxide (TPAH) , Tetrabutylammonium Hydroxide (TBAH), Benzyltrimethylammonium Hydroxide (BTMAH), Benzyltriethylammonium Hydroxide (BTEAH), Choline Hydroxide, Ammonium Hydroxide, Dodecyltrimethyl One or more of ammonium hydroxide (DTAH) and cetyltrimethylammonium hydroxide (CTOH);

The organic amine is selected from monoethylamine, diethylamine, triethylamine, tripropylamine, N'N-diethylethylenediamine, hydroxyethylethylenediamine, cyclohexylamine, 1,2-propylenediamine , one or more of pentamethyldiethylenetriamine;

The organic alcohol amine is selected from one or more of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), isopropanolamine, N-methylethanolamine .
The chemical cleaning solution according to claim 12, characterized in that,

The mass percent content of the organic base is 0.1wt%-10wt%.
cleaning solution as claimed in claim 1, is characterized in that,

Ammonium salts of organic acids are further included.
The cleaning solution according to claim 15, characterized in that,

The organic acid ammonium salt is selected from ammonium formate, ammonium oxalate, ammonium lactate, ammonium tartrate, triammonium citrate, ammonium acetate, ammonium carbamate, ammonium carbonate, ammonium benzoate, tetraammonium EDTA, triammonium EDTA, diammonium EDTA , ammonium succinate, ammonium 1-H-pyrazole-3-formate, ammonium malonate, ammonium adipate, and ammonium iminodiacetate.
The cleaning solution according to claim 15, characterized in that,

The mass percent content of the organic acid ammonium salt is 0.01wt%-50wt%.
An application method of using the cleaning solution described in any one of claims 1-17 for cleaning cobalt.
The application method according to claim 18, characterized in that,

The applied temperature is 20-80°C, and the pH value is 4-12.