Etching residue remover composition

Abstract

An etching residue remover composition. The etching residue remover composition comprises a hydroxylamine and a derivative thereof, a surfactant, a metal corrosion inhibitor, an amine pH regulator, a nitrogen-containing organic acid, and water. The etching residue remover composition is used in the process of cleaning a cobalt layer of 7 nm or above, has relatively good cleaning capacity for polymer residues, metal oxides and fluorides after ashing of a photoresist and plasma, also has very good compatibility with metal materials such as Co and TiN and low-K materials such as SiN, silicon oxide and TEOS, and has a large process operation window and good application prospects.

Description

Etching residue remover composition Technical Field

[0001] The present invention relates to an etching residue remover composition, and more particularly to a cleaning composition. Background Art

[0002] Photoresist plays a crucial role in semiconductor manufacturing, allowing a series of patterns to be transferred onto wafer substrates. Photoresist removal is a crucial step in semiconductor manufacturing, effectively minimizing the impact on subsequent processes. There are two main methods for removing photoresist: dry and wet. Wet methods are the mainstream, but wet methods can result in incomplete removal of photoresist that has hardened after ICP or ion implantation. Furthermore, dry photoresist removal can produce difficult-to-remove organic-metal crosslinked products, further complicating the process. In recent years, with the continuous advancement of process nodes toward more advanced manufacturing processes, the requirements for photoresist removal have become increasingly stringent. This is particularly true with the use of Co in some layers above 7nm, replacing Cu. Protecting metals like Co during photoresist removal is crucial. A photoresist that effectively removes plasma etching and ashing residues and is non-corrosive to all exposed substrate materials is essential, especially for the use of Co in some layers above 7nm.

[0003] CN105849245B mentions the addition of at least one chelating agent, which is a polyamino polycarboxylic acid. Aminocarboxyl chelating agents are a class of organic compounds with hydrophilicity and chelation, and contain amino and carboxyl groups in their molecular structure. Such compounds have good metal ion chelation and coordination. Aminocarboxyl chelating agents, through coordination with metal ions, form metal complexes that can make the metal ions in the solution inactive, preventing metal oxidation and corrosion: Aminocarboxyl chelating agents can effectively prevent metal oxidation and corrosion in water, thereby protecting the metal surface. However, aminocarboxyl chelating agents have poor desorption ability on the surface of materials, mainly due to the following reasons: 1. Molecular structure limitations: carboxyl and amine groups are present in the molecular structure of aminocarboxyl chelating agents, making its molecular structure more complex, and the intermolecular force is strong, resulting in strong adsorption of molecules on the surface of the material, making it difficult to desorb from the surface. 2. Lack of a specific structure: Some surfactants with specific small molecular structures, such as sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS), have better desorption ability on material surfaces because their simple molecular structure makes them easy to desorb from the surface. 3. Counterion interaction: When aminocarboxylic chelating agents form complexes with metal ions, counterion interaction occurs, which strengthens the interaction between the chelating agent and the surface and weakens the desorption ability. Therefore, it has a certain impact on the subsequent filling of other materials.

[0004] Therefore, there is a need in the art for a composition for removing residues that avoids the use of aminocarboxyl chelating agents, which can not only provide excellent removal effects but also reduce corrosion to materials.

[0005] Summary of the Invention

[0006] The present invention discloses an etching residue remover composition with excellent cleaning capabilities for photoresist, polymer residues after plasma ashing, metal oxides, and fluorides. It is suitable for cleaning cobalt layers thicker than 7nm. It also exhibits excellent compatibility with metals such as Co and TiN, as well as Low-K materials. Post-cleaning residues are minimal, facilitating subsequent operations. This composition has a wide process window and promising application prospects.

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

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

[0009] Furthermore, the surfactant can be selected from alcohol ether solvents, including 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-propylene glycol, 1,3-propylene glycol, benzyl alcohol, dioxane, ethanol, n-propanol, isopropanol, n-butanol; it can also be selected from non-ionic surfactants, including SUPERWET-320, SUPERWET-340, SUPERWET-360, SURFYNOL420, SURFYNOL440, coconut fatty acid diethanolamide. Cationic surfactants may also be selected from the group consisting of dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, benzalkonium chloride, dodecylbenzyldimethylammonium chloride, hexadecyltrimethylammonium bromide, and tetraheptylammonium bromide.

[0010] Furthermore, the metal corrosion inhibitor is selected from one or more of pyrazole, 1-methylpyrazole, 3,5-dimethylpyrazole, pyrazine, benzotriazole, methylbenzotriazole, 1H-benzotriazole methanol, 1,2,4-triazole-3-carboxylic acid methyl ester, 5-benzyl-1H-tetrazole, 1-phenyl-5-mercaptotetrazole, 5-benzylthio-1H-tetrazole, 5-methyltetrazole, 2-mercaptothiadiazole, methimazole, mercaptoimidazole, and 3-mercapto-4-methyl-4H-1,2,4-triazole.

[0011] Furthermore, the amine pH regulator is selected from one or more of diglycolamine, ethanolamine, ethylenediamine, diethanolamine, diethylenetriamine, triethylenetetramine, hydroxyethylethylenediamine, N-methylethanolamine, n-propanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, and triethylenetetramine.

[0012] Furthermore, the nitrogen-containing organic acid is selected as a polycarboxylic acid containing one nitrogen atom. Further, the polycarboxylic acid containing one nitrogen atom is selected from one or more of iminodiacetic acid, iminodipropionic acid, iminodisuccinic acid, N-(2-acetylamino)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%-10%, preferably 0.5%-10%.

[0014] Furthermore, the mass percentage of the surfactant is 0.001%-10%, preferably 0.001%-5%.

[0015] Furthermore, the mass percentage of the metal corrosion inhibitor is 0.01%-3%.

[0016] Furthermore, the mass percentage of the amine pH regulator is 0.01%-5%.

[0017] Furthermore, the pH value of the composition is in the range of 7-10, preferably in the range of 8-9.

[0018] Furthermore, the mass percentage of the nitrogen-containing organic acid is 0.01%-5%.

[0019] All reagents in this application are commercially available.

[0020] Compared with the prior art, the advantages of the present invention are:

[0021] Provided is an etching residue remover composition with excellent photoresist removal capabilities and no aminocarboxylic chelating agents. The composition is used for cleaning cobalt layers thicker than 7nm. It has excellent cleaning capabilities for polymer residues, metal oxides, and fluorides after plasma ashing. It also exhibits excellent compatibility with TiN and Low-K materials, a wide process window, and promising application prospects. This composition addresses the technical issue of aminocarboxylic chelating agents having poor desorption capabilities on material surfaces, which can affect subsequent filling with other materials. DETAILED DESCRIPTION

[0022] The advantages of the present invention are described in detail below with reference to specific embodiments.

[0023] The cleaning composition according to the present invention is described in detail below through examples and test results, but is not limited to these examples and the test results shown. The cleaning composition of the present invention can be embodied in a variety of specific formulations, wherein the specific components of the composition are described in terms of weight percentage for all such cleaning compositions.

[0024] Preparation method: According to the formulations (specific components and their corresponding specific contents) of the embodiments and comparative examples in Table 1 below, the components were simply mixed.

[0025] Table 1 Some embodiments of the present invention

[0026] The units of the above contents are all mass percentages.

[0027] In order to investigate the compatibility of the composition with various materials, the etching rates of metal Co, TiN, non-metal silicon oxide and SiN were further tested.

[0028] The metal etch rate test method is as follows: Co and TiN blank wafers are selected, sliced ​​into 5*5cm sizes, and placed in a single-wafer spin cleaner for processing. The processing time range is 3-20 minutes, preferably 10 minutes, the rotation speed setting range is 200-900rpm, preferably 600rpm, and the test temperature is 25-70°C, preferably 50°C. After processing, the blank wafers are removed, rinsed, and blown dry with high-purity nitrogen.

[0029] The corrosion rate test method is as follows:

[0030] 1) Use a metal film thickness gauge to measure the resistance (R1) of a 5*5cm metal blank wafer to be tested;

[0031] 2) Place the 5*5cm metal blank wafer to be tested in a single wafer spin cleaning machine;

[0032] 3) Remove the 5*5cm metal blank wafer, rinse it with deionized water, blow dry it with high-purity nitrogen, and then use a metal film thickness gauge to measure the resistance (R2) of the metal blank wafer;

[0033] 4) By inputting the above resistance value change and processing time into a suitable program, the etching rate can be calculated. The calculation formula is as follows:

[0034] ER=K(R2-R1) / T

[0035] Among them, R1 and R2 are the resistance values ​​of the metal blank wafer; T is the processing time of the single chip microcomputer; K value is the coefficient, and the K value of different metal materials is different. The unit of metal corrosion rate is

[0036] The etch rate test method for non-metallic materials (SiN, silicon oxide) is as follows:

[0037] 1) Using an ellipsometer to measure the first thickness D1 of the non-metallic material layer (AlN) of a 5*5cm non-metallic blank wafer to be tested;

[0038] 2) Place the 5*5cm non-metallic blank wafer to be tested in a single-wafer spin cleaning machine for 3 to 20 minutes, with the speed set at 200 to 900 rpm;

[0039] 3) Take out the blank wafer, rinse it with deionized water, blow dry it with high-purity nitrogen, and then use an ellipsometer to measure the second thickness D2;

[0040] 4) By inputting the above thickness changes and processing time into a suitable program, the corrosion rate can be calculated. The calculation formula is as follows:

[0041] ER=(D1-D2) / T

[0042] Wherein, D1 and D2 are the first thickness and the second thickness of the non-metal blank wafer respectively; T is the processing time.

[0043] The measured etching rates are shown in Table 2.

[0044] Table 2 Etching rate of blank wafers by compositions of Examples 1-13 of the present invention

[0045] The results in Table 2 show that within the operating window of 25-70°C, 200-900 rpm, and 3-20 min, the etching rates for Co, TiN, silicon oxide, and SiN are relatively low. The composition exhibits good compatibility with all four materials at various temperatures, rotation speeds, and operating times.

[0046] Table 3 Some Examples of the Present Invention and Comparative Examples

[0047] To investigate the residual organic matter on wafer surfaces after treatment with the composition, the present invention conducted tests on Examples 14 and 15 and Comparative Examples 4 and 5 listed in Table 3. The following technical procedures were employed: Co blank wafers were sliced ​​into 5x5cm sections and processed in a single-wafer spin-cleaner for 3 minutes at a speed of 600 rpm and a test temperature of 40°C. After treatment, the wafers were removed and rinsed on a microcontroller for 30 seconds at a speed of 600 rpm and a temperature of 25°C. Finally, the wafers were dried with high-purity nitrogen gas, and the elemental abundances of C, N, O, and Co on the wafer surfaces were measured using XPS. The test results are shown in Table 4.

[0048] Table 4 XPS results of Co wafer surface after treatment

[0049] As shown in Table 4, the Co surface after being treated with the composition example has a higher Co abundance and lower N and C abundances, indicating that the amount of residual organic matter in the system is lower than that in the comparative example system, which is beneficial for subsequent operations on the Co layer, such as filling W or other metals into related structures.

[0050] Table 5 Test results of Co ion content (ppb) in some examples

[0051] Table 5 shows the solubility of CoF2 and CoO in some examples, with deionized water as the blank. The testing method employed in the present invention is to dissolve equal amounts of CoF2 / CoO in 1 L of the composition solution or water, respectively, and measure the Co ion concentration by ICP-MS after stabilization. It can be seen that the composition of the present invention has a much greater solubility for CoF2 / CoO than deionized water, demonstrating that the composition can effectively remove cobalt fluoride and oxide from the sidewalls or top of plasma-treated surfaces.

[0052] In summary, the present invention demonstrates the following positive advances: The present invention discloses an etching residue remover composition that does not contain aminocarboxylic chelating agents. It exhibits excellent cleaning capabilities for photoresist, polymer residues after plasma ashing, metal oxides, and fluorides. It is suitable for cleaning cobalt layers exceeding 7nm in thickness. It also exhibits excellent compatibility with metals such as Co and TiN, as well as Low-K materials. Post-cleaning residues are minimal, facilitating subsequent operations. This composition offers a wide process window and promising application prospects.

[0053] While the specific embodiments of the present invention have been described in detail above, these are merely exemplary and the present invention is not limited thereto. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, any equivalent changes and modifications made without departing from the spirit and scope of the present invention are intended to be encompassed within the scope of the present invention.

Claims

1. An etching residue remover composition, characterized in that include: 1) Hydroxylamine and its derivatives; 2) Surfactants; 3) Metal corrosion inhibitors; 4) Amine pH regulator; 5) Nitrogen-containing organic acids; 6) Water.

2. The composition according to claim 1, characterized in that The hydroxylamine and its derivatives are selected from one or more of 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 and its derivatives is 0.1%-10%.

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

5. The composition according to claim 1, characterized in that The surfactant is selected from alcohol ether solvents, including: 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-propylene glycol, 1,3-propylene glycol, benzyl alcohol, dioxane, ethanol, n-propanol, isopropanol, n-butanol or one or more thereof.

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

7. The composition of claim 1, characterized in that The surfactant is selected from cationic surfactants, including: one or more of dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, benzalkonium chloride, dodecylbenzyldimethylammonium chloride, hexadecyltrimethylammonium bromide, tetraheptylammonium bromide.

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

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

10. The composition of claim 1, characterized in that The metal corrosion inhibitor is selected from one or more of pyrazole, 1-methylpyrazole, 3,5-dimethylpyrazole, pyrazine, benzotriazole, methylbenzotriazole, 1H-benzotriazole methanol, 1,2,4-triazole-3-carboxylic acid methyl ester, 5-benzyl-1H-tetrazole, 1-phenyl-5-mercaptotetrazole, 5-benzylthio-1H-tetrazole, 5-methyltetrazole, 2-mercaptothiadiazole, methimazole, mercaptoimidazole, and 3-mercapto-4-methyl-4H-1,2,4-triazole.

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

12. The composition of claim 1, characterized in that The amine pH regulator is selected from one or more of diglycolamine, ethanolamine, ethylenediamine, diethanolamine, diethylenetriamine, triethylenetetramine, hydroxyethylethylenediamine, N-methylethanolamine, n-propanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, and triethylenetetramine.

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

14. The composition of claim 1, characterized in that The adjustment range of the amine pH regulator is 7-10.

15. The composition of claim 1, characterized in that The adjustment range of the amine pH regulator is 8-9.

16. The composition of 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 selected from one or more of iminodiacetic acid, iminodipropionic acid, iminodisuccinic acid, N-(2-acetylamino)iminodiacetic acid, N-(phosphonomethyl)iminodiacetic acid, nitrilotriacetic acid, glutamic acid, and aspartic acid.

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

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