Etching residue removal agent composition

Abstract

The present invention relates to an etching residue removal agent composition. This composition contains hydroxylamine or a derivative thereof, a surfactant, a metal corrosion inhibitor, an amine-based pH adjuster, a nitrogen-containing organic acid, and water. This composition can be used for cleaning in cobalt layer processes of 7 nm or more, and has excellent cleaning ability against resists, residual polymers after plasma ashing, metal oxides, and fluorides, while having good compatibility with metallic materials such as Co and TiN, and low-K materials such as SiN, silicon dioxide, and TEOS, and has a wide process window and good prospects for practical application.

Description

[Technical Field]

[0001] The present invention relates to an etching residue remover composition. More specifically, it relates to a cleaning composition. [Background Art]

[0002] In semiconductor manufacturing processes, photoresist plays a significant role: a series of patterns can be transferred onto a wafer substrate via the resist, and removal of the resist is also a key step in the semiconductor manufacturing process, which can effectively reduce the influence on subsequent processes. Methods for removing resist mainly include dry methods and wet methods, with wet methods being mainstream. However, for photoresist that has been "cured" after certain ICP or ion implantation processes, the wet method may result in insufficient resist removal. At the same time, the dry resist removal process also produces organic-metal crosslinked products that are difficult to remove, increasing the difficulty of resist removal. In recent years, as process nodes have advanced to increasingly sophisticated manufacturing processes, requirements for resist removal have become increasingly stringent. Especially for processes of 7 nm and beyond, cobalt is used in some layers instead of copper, and it is necessary to achieve resist removal while also providing good protection for metals such as cobalt. The composition is required to effectively remove plasma etching residues and plasma ashing residues, be non-corrosive to all exposed substrate materials, and particularly be non-corrosive to cobalt when cobalt is used in certain layers in processes of 7 nm and beyond.

[0003] Patent Document 1 (CN105849245B) describes the addition of at least one chelating agent, which is a polyaminopolycarboxylic acid. Aminocarboxylic acid chelating agents are a type of organic compound that is hydrophilic and chelating, and their molecular structure contains an amino group and a carboxyl group. These types of compounds have good chelating and coordinating properties with metal ions, and the metal complexes formed by the coordination of aminocarboxylic acid chelating agents with metal ions inactivate metal ions in solution, suppressing metal oxidation and corrosion. Aminocarboxylic acid chelating agents can effectively prevent metal oxidation and corrosion in water and protect metal surfaces. However, aminocarboxylic acid chelating agents have low deadsorption capacity from material surfaces, mainly for the following reasons: 1. Molecular structure limitations: Aminocarboxylic acid chelating agents have a complex molecular structure in which carboxyl groups and amino groups coexist. The intermolecular forces are strong, causing the molecules to strongly adsorb to the material surface and be difficult to detach from the surface. 2. Lack of specific structure: Surfactants with specific small molecular structures, such as sodium dodecyl sulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS), exhibit good deadsorption capabilities on material surfaces. This is because their molecular structures are simple, making deadsorption from the surface easy. 3. Antiionic action: When aminocarboxylic acid-based chelating agents form complexes with metal ions, antiionic action occurs, increasing the interaction force between the chelating agent and the surface, and weakening its deadsorption capacity. Therefore, it has a certain effect on the subsequent filling of other materials.

[0004] Therefore, in this technical field, there is a need for etching residue removal compositions that do not use aminocarboxylic acid-based chelating agents, which should not only provide excellent removal effects but also reduce corrosion to the material. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Chinese Patent No. CN105849245B [Overview of the project] [Problems that the invention aims to solve]

[0006] This invention relates to an etching residue removal agent composition that has good cleaning ability against resists, polymer residues after plasma ashing, metal oxides, and fluorides, and is used for cleaning cobalt layer processes of 7 nm or more. At the same time, it has good compatibility with metals such as Co and TiN and low-K materials, and produces little residue after cleaning, which is advantageous for subsequent operations. The process window of this composition is wide and the prospects for practical application are good. [Means for solving the problem]

[0007] The present invention provides an etching residue removal agent composition. This composition contains 1) hydroxylamine and its derivatives; 2) surfactant; 3) metal corrosion inhibitor; 4) amine-based pH adjuster; 5) nitrogen-containing organic acid; and 6) water.

[0008] Furthermore, the hydroxylamine and its derivatives are one or more selected from hydroxylamine, N-methylhydroxylamine, N,N-dimethylhydroxylamine, N-ethylhydroxylamine, N,N-diethylhydroxylamine, acetohydroxamic acid, and o-benzylhydroxylamine.

[0009] Furthermore, the surfactant is selected from alcohol ether solvents, which include ethylene glycol monobutyl ether, ethylene glycol glycidyl ether, poly(ethylene glycol-propylene glycol) monobutyl ether, diethylene glycol dimethyl ether, propylene glycol phenyl ether, propylene glycol methyl ether, dodecylamine polyoxyethylene ether, polyethylene glycol, polyethylene glycol-propylene glycol copolymer, n-hexanol, 1,2-pentanediol, 1,2-propanediol, 1,3-propanediol, benzyl alcohol, dioxane, ethanol, n-propanol, isopropanol, and n-butanol; Alternatively, a nonionic surfactant may be selected, and said nonionic surfactant includes SUPERWET-320, SUPERWET-340, SUPERWET-360, SURFYNOL420, SURFYNOL440, and coconut fatty acid diethanolamide; Alternatively, a cationic surfactant may be selected, and said cationic surfactant includes dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, benzalkonium chloride, dodecylbenzyldimethylammonium chloride, cetyltrimethylammonium bromide, and tetraheptylammonium bromide.

[0010] Furthermore, the metal corrosion inhibitor is characterized by being one or more selected from pyrazole, 1-methylpyrazole, 3,5-dimethylpyrazole, pyrazine, benzotriazole, methylbenzotriazole, 1H-benzotriazolemethanol, 1,2,4-triazole-3-carboxylate methyl, 5-benzyl-1H-tetrazol, 1-phenyl-5-mercaptotetrazol, 5-benzylthio-1H-tetrazol, 5-methyltetrazol, 2-mercaptothiadiazole, methimazole, mercaptoimidazole, and 3-mercapto-4-methyl-4H-1,2,4-triazole.

[0011] Furthermore, the amine-based pH adjuster is characterized by being one or more selected from diethylene glycolamine, ethanolamine, ethylenediamine, diethanolamine, diethylenetriamine, triethylenetetramine, hydroxyethylethylenediamine, N-methylethanolamine, n-propanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, and triethylenetetramine.

[0012] Furthermore, the nitrogen-containing organic acid is a polycarboxylic acid containing one nitrogen atom, and the polycarboxylic acid containing one nitrogen atom is one or more selected from iminodiacetic acid, iminodipropionic acid, iminodisuccinic acid, N-(2-acetamide)iminodiacetic acid, N-(phosphonomethyl)iminodiacetic acid, nitrilotriacetic acid, glutamic acid, and aspartic acid.

[0013] Furthermore, the mass percentage of the hydroxylamine and its derivatives is 0.1 to 10%, preferably 0.5 to 10%. Furthermore, the mass percentage of the surfactant is 0.001 to 10%, preferably 0.001 to 5%. Furthermore, the mass percentage of the metal corrosion inhibitor is 0.01 to 3%. Furthermore, the mass percentage of the amine-based pH adjuster is 0.01 to 5%. Furthermore, the pH range of the composition is 7 to 10, preferably 8 to 9. Furthermore, the mass percentage of the nitrogen-containing organic acid is 0.01 to 5%.

[0014] All reagents used in this application are commercially available. [Effects of the Invention]

[0015] Compared to the prior art, the advantages of the present invention are as follows: Provided is an etching residue removing agent composition which has excellent resist removing capability and does not contain an aminocarboxylic acid-based chelating agent. The composition is used for cleaning a cobalt layer process of 7 nm or more, has good cleaning capability for polymer residues, metal oxides and fluorides after plasma ashing, simultaneously has good compatibility with TiN and Low-K materials, has a wide process window, and has good prospects for practical application. The present invention solves the problem that the aminocarboxylic acid-based chelating agent has poor desorption capability from the material surface and exerts a certain influence on the subsequent filling of other materials. Description of Embodiments

[0016] [Examples, etc.] Hereinafter, advantages of the present invention will be described in detail with reference to specific embodiments. Hereinafter, the cleaning liquid composition according to the present invention will be described in detail through examples and test results, but the present invention is not limited to these examples and respective test results. The cleaning liquid composition of the present invention can be embodied as a plurality of specific formulations, and the specific components of the composition therein are discussed in mass%.

[0017] Preparation method: Each component is simply mixed according to the formulations (specific components and their corresponding specific contents) of each example and comparative example shown in Table 1 below.

[0018] Table 1: Partial examples of the present invention [Table 1] JPEG2026529499000002.jpg242170JPEG2026529499000003.jpg240170JPEG2026529499000004.jpg242170JPEG2026529499000005.jpg241170JPEG2026529499000006.jpg244170JPEG2026529499000007.jpg181170

[0019] All the above contents are in mass%.

[0020] In order to evaluate the compatibility of the composition with various materials, the etching rates of metallic cobalt, TiN, non-metallic silicon oxide and SiN were further tested.

[0021] The metal etching rate test method is as follows. After dicing Co and TiN blanket wafers into pieces of 5 cm×5 cm, the pieces are placed on a single-substrate rotary cleaning apparatus, and processing is carried out under the conditions of a processing time of 3 to 20 minutes (preferred time: 10 minutes), a rotation speed of 200 to 900 rpm (preferred rotation speed: 600 rpm), and a temperature of 25 to 70°C (preferred temperature: 50°C). After the processing is completed, the substrate is pulled up, rinsed with deionized water, and dried with high-purity nitrogen gas.

[0022] The etching rate measurement method is as follows: 1) Using a metal thin film thickness measuring apparatus, measure the resistance value (R1) of an untreated 5 cm×5 cm metal blanket wafer. 2) Set the aforementioned 5 cm×5 cm untreated metal blanket wafer on a single-substrate rotary cleaning apparatus and carry out the processing. 3) Take out the processed metal blanket wafer, after going through a rinsing step with deionized water, dry it with high-purity nitrogen gas, and measure the resistance value (R2) again with the metal thin film thickness measuring apparatus. 4) Input the amount of change in resistance value (R2-R1) and the processing time into a dedicated analysis algorithm, and calculate the etching rate by the following calculation formula. The calculation formula is as follows: ER=K(R2-R1) / T Here, R1 and R2 represent the resistance values of the metal blanket wafer, T represents the processing time of the single-substrate rotary cleaning apparatus. K is a constant that differs for each metal material. The unit of metal etching rate is Å / min.

[0023] The etching rate measurement method for non-metallic materials (SiN, silicon oxide) is as follows: 1) Using an ellipsometer, measure the first thickness D1 of the non-metallic material layer (AlN) of an untreated 5 cm×5 cm non-metallic blanket wafer. 2) The 5cm x 5cm non-metallic blanket wafer is placed in a single-substrate rotary cleaning apparatus, and the cleaning process is performed under the conditions of a rotation speed of 200 to 900 rpm and a processing time of 3 to 20 minutes. 3) After processing, the blanket wafer is removed, rinsed with deionized water, and dried with high-purity nitrogen gas. The second thickness D2 is then measured using the same ellipsometer. 4) Input the above thickness value change and processing time into an appropriate program and calculate the corrosion rate. The calculation formula is as follows: ER=(D1-D2) / T Here, D1 and D2 represent the first and second thicknesses of the non-metallic blanket wafer, respectively, and T represents the processing time.

[0024] The measured etching rates are shown in Table 2.

[0025] Table 2: Etching rates of compositions from Examples 1 to 13 of the present invention on a blanket wafer [Table 2]

[0026] The results in Table 2 show that the etching rates of Co, TiN, silicon dioxide, and SiN are low within a process window of operating temperature 25–70°C, rotation speed 200–900 rpm, and operating time 3–20 minutes. The composition exhibits good compatibility with the above four materials under different temperatures, rotation speeds, and operating times.

[0027] Table 3: Some Examples and Comparative Examples of the Invention [Table 3] JPEG2026529499000010.jpg90170

[0028] To evaluate the state of organic residue after the composition has treated the wafer surface, the present invention selected Examples 14 and 15 and Comparative Examples 4 and 5 (comparison 4 and 5) from Table 3 and conducted tests. The following technical procedures were employed: A Co blanket wafer was selected, diced into 5cm x 5cm pieces, and then placed in a single-substrate rotary cleaning apparatus. The cleaning process was performed under the conditions of a processing time of 3 minutes, a rotation speed of 600 rpm, and a temperature of 40°C. After the processing was completed, the wafer was removed and transferred to the single-substrate rotary cleaning apparatus. Rinsing was performed for a processing time of 30 seconds, at a rotation speed of 600 rpm and a temperature of 25°C, and finally, drying was performed using high-purity nitrogen gas. Subsequently, surface elemental analysis was performed using XPS to measure the elemental abundances of C, N, O, and Co. The test results are shown in Table 4.

[0029] Table 4: XPS analysis results of the surface of the Co blanket wafer after treatment [Table 4]

[0030] As is clear from Table 4, the Co surface treated in the examples of the composition has a high abundance of Co and low abundance of N and C. This indicates that the amount of residual organic matter in the composition system is lower than in the comparative example system, which is advantageous for subsequent processes on the Co layer (e.g., filling of the related structure with tungsten (W) or other metals).

[0031] Table 5: Co ion content (ppb) test results for some examples [Table 5]

[0032] Table 5 shows data illustrating the solubility of CoF2 and CoO in some examples, with deionized water used for the blank test. The test method employed in this invention is as follows: Equal amounts of CoF2 / CoO were dissolved in 1 L of the composition solution or deionized water, respectively, and the solutions were stabilized and the cobalt ion concentration was measured by ICP-MS. It can be seen that the composition of this invention has a much greater solubility of CoF2 / CoO than deionized water. This indicates that this composition can effectively remove cobalt fluorides and oxides from the sidewalls or top after plasma treatment.

[0033] Based on the above, the positive effects of the present invention are as follows: This invention discloses an etching residue removal agent composition that does not contain an aminocarboxylic acid-based chelating agent, which has good cleaning ability against resists, polymer residues after plasma ashing, metal oxides, and fluorides, and can be used for cleaning cobalt layer processes of 7 nm or more. At the same time, it has good compatibility with metals such as Co and TiN and low-K materials, and produces little residue after cleaning, which is advantageous for subsequent operations. This composition has a wide process window and good prospects for practical application.

[0034] Although specific embodiments of the present invention have been described in detail above, these are merely illustrative examples, and the present invention is not limited to the above-described embodiments. To those skilled in the art, all equivalent modifications and substitutions made to the present invention fall within the scope of the present invention. Therefore, all equivalent changes and modifications made without departing from the spirit and scope of the present invention should be included within the scope of the present invention.

Claims

1. An etching residue removal agent composition comprising the following components: 1) Hydroxylamine or its derivatives; 2) Surfactants; 3) Metal corrosion inhibitors; 4) Amine-based pH adjusters; 5) Nitrogen-containing organic acids; 6) water An etching residue removal agent composition characterized by containing the following:

2. The composition according to claim 1, characterized in that the hydroxylamine or its derivative is one or more selected from hydroxylamine, N-methylhydroxylamine, N,N-dimethylhydroxylamine, N-ethylhydroxylamine, N,N-diethylhydroxylamine, acetohydroxamic acid, and o-benzylhydroxylamine.

3. The composition according to claim 1, characterized in that the mass percentage of the hydroxylamine or its derivative is 0.1 to 10%.

4. The composition according to claim 1, characterized in that the mass percentage of the hydroxylamine or its derivative is 0.5 to 10%.

5. The surfactant is selected from alcohol ether solvents, The composition according to claim 1, characterized in that the alcohol ether solvent is one or more selected from the group consisting of ethylene glycol monobutyl ether, ethylene glycol glycidyl ether, poly(ethylene glycol-propylene glycol) monobutyl ether, diethylene glycol dimethyl ether, propylene glycol phenyl ether, propylene glycol methyl ether, dodecylamine polyoxyethylene ether, polyethylene glycol, polyethylene glycol-propylene glycol copolymer, n-hexanol, 1,2-pentanediol, 1,2-propanediol, 1,3-propanediol, benzyl alcohol, dioxane, ethanol, n-propanol, isopropanol, and n-butanol.

6. The aforementioned surfactant is selected from nonionic surfactants. The composition according to claim 1, characterized in that the nonionic surfactant is one or more selected from the group consisting of SUPERWET-320, SUPERWET-340, SUPERWET-360, SURFYNOL420, SURFYNOL440, and coconut fatty acid diethanolamide.

7. The aforementioned surfactant is selected from cationic surfactants, The composition according to claim 1, characterized in that the cationic surfactant is one or more selected from the group consisting of dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, benzalkonium chloride, dodecylbenzyldimethylammonium chloride, cetyltrimethylammonium bromide, and tetraheptylammonium bromide.

8. The composition according to claim 1, characterized in that the mass percentage of the surfactant is 0.001 to 10%.

9. The composition according to claim 1, characterized in that the mass percentage of the surfactant is 0.001 to 5%.

10. The composition according to claim 1, characterized in that the metal corrosion inhibitor is one or more selected from pyrazole, 1-methylpyrazole, 3,5-dimethylpyrazole, pyrazine, benzotriazole, methylbenzotriazole, 1H-benzotriazolemethanol, 1,2,4-triazole-3-carboxylate methyl, 5-benzyl-1H-tetrazol, 1-phenyl-5-mercaptotetrazol, 5-benzylthio-1H-tetrazol, 5-methyltetrazol, 2-mercaptothiadiazole, methimazole, mercaptoimidazole, and 3-mercapto-4-methyl-4H-1,2,4-triazole.

11. The composition according to claim 1, characterized in that the mass percentage of the metal corrosion inhibitor is 0.01 to 3%.

12. The composition according to claim 1, characterized in that the amine-based pH adjuster is one or more selected from diethylene glycolamine, ethanolamine, ethylenediamine, diethanolamine, diethylenetriamine, triethylenetetramine, hydroxyethylethylenediamine, N-methylethanolamine, n-propanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, and triethylenetetramine.

13. The composition according to claim 1, characterized in that the mass percentage of the amine-based pH adjuster is 0.01 to 5%.

14. The composition according to claim 1, characterized in that the pH adjustment range by the amine-based pH adjuster is 7 to 10.

15. The composition according to claim 1, characterized in that the pH adjustment range by the amine-based pH adjuster is 8 to 9.

16. The composition according to claim 1, characterized in that the nitrogen-containing organic acid is selected from polycarboxylic acids containing one nitrogen atom.

17. The composition according to claim 16, characterized in that the polycarboxylic acid containing one nitrogen atom is one or more selected from iminodiacetic acid, iminodipropionic acid, iminodisuccinic acid, N-(2-acetamide)iminodiacetic acid, N-(phosphonomethyl)iminodiacetic acid, nitrilotriacetic acid, glutamic acid, and aspartic acid.

18. The composition according to claim 1, characterized in that the mass percentage of the nitrogen-containing organic acid is 0.01 to 5%.

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