High Oxide Film Removal Rate Shallow Trench (STI) Chemical Mechanical Planarization (CMP) Polishing
20230020073 · 2023-01-19
Assignee
Inventors
- Xiaobo Shi (Chandler, AZ, US)
- Krishna P. Murella (Phoenix, AZ, US)
- Joseph D. Rose (Gilbert, AZ, US)
- Hongjun Zhou (Chandler, AZ, US)
- Mark Leonard O'Neill (Queen Creek, AZ, US)
Cpc classification
B24B37/044
PERFORMING OPERATIONS; TRANSPORTING
International classification
B24B37/04
PERFORMING OPERATIONS; TRANSPORTING
Abstract
High oxide film removal rate Shallow Trench Isolation (STI) chemical mechanical planarization (CMP) polishing compositions, methods, and systems of use therefore are provided. The CMP polishing composition comprises abrasives of ceria coated inorganic oxide particles, such as ceria-coated silica; and a chemical additive for providing a high oxide film removal rate. The chemical additive is a gelatin molecule possessing negative and positive charges on the same molecule.
Claims
1. A chemical mechanical planarization polishing composition comprising: ceria-coated inorganic oxide particles; a gelatin molecule comprising organic carboxylate functional groups providing negative charges and protonated organic amino groups providing the positive charges on the same molecule; a water soluble solvent selected from the group consisting of deionized (DI) water, distilled water, and alcoholic organic solvents; and optionally a biocide; and a pH adjuster; wherein the composition has a pH value of 3 to 10.
2. The chemical mechanical planarization polishing composition of claim 1, wherein the ceria-coated inorganic oxide particles have a concentration of from 0.02 wt. % to 10 wt. %: and the ceria-coated inorganic oxide particles are selected from the group consisting of ceria-coated colloidal silica, ceria-coated high purity colloidal silica, ceria-coated alumina, ceria-coated titania, ceria-coated zirconia particles and combinations thereof.
3. (canceled)
4. The chemical mechanical planarization polishing composition of claim 1, wherein the gelatin molecule further comprises organic amide functional groups, and 5-membered non-aromatic rings with one nitrogen atom as a hetero-atom.
5. (canceled)
6. The chemical mechanical planarization polishing composition of claim 1, wherein the gelatin molecule is an organic gelatin molecule made from an animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof; wherein the gelatin molecule has a concentration of 0.0001 wt.% to 5 wt. %.
7. The chemical mechanical polishing composition of claim 1, wherein the gelatin molecule has a molecular structure of: ##STR00002##
8. (canceled)
9. (canceled)
10. (canceled)
11. The chemical mechanical planarization polishing composition of claims 1, wherein the biocide having an active ingredient of 5-chloro-2-methyl-4-isothiazolin-3-one or 2-methyl-4-isothiazolin-3-one; and the biocide having a concentration of from 0.0001 wt. % to 0.05 wt. %; the pH adjuster selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof for acidic pH conditions; or selected from the group consisting of sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkyl ammonium hydroxide, organic quaternary ammonium hydroxide compounds, organic amines, and combinations thereof for alkaline pH conditions; and the pH adjuster having a concentration of from 0 wt. % to 1 wt. %.
12. (canceled)
13. (canceled)
14. (canceled)
15. The chemical mechanical planarization polishing composition of claim 1, wherein the composition comprises ceria-coated colloidal silica particles as the ceria-coated inorganic oxide particles, the gelatin molecule made from animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof; and the pH value of the chemical mechanical planarization polishing composition is 4 to 9.
16. (canceled)
17. (canceled)
18. A method of chemical mechanical planarization (CMP) a semiconductor substrate having at least one surface comprising a silicon dioxide film, comprising providing the semiconductor substrate; providing a polishing pad; providing the a chemical mechanical planarization polishing composition comprising: ceria-coated inorganic oxide particles selected from the group consisting of ceria-coated colloidal silica, ceria-coated high purity colloidal silica, ceria-coated alumina, ceria-coated titania, ceria-coated zirconia particles and combinations thereof and the ceria-coated inorganic oxide particles have a concentration of from 0.02 wt. % to 10 wt. %; a gelatin molecule comprising organic carboxylate functional groups providing negative charges and protonated organic amino groups providing the positive charges on the same molecule; and the gelatin molecule has a concentration of 0.0001 wt. % to 5 wt. %; a water soluble solvent selected from the group consisting of deionized (DI) water, distilled water, and alcoholic organic solvents; and optionally a biocide; and a pH adjuster; wherein the composition has a pH value of 3 to 10; contacting the semiconductor substrate with the polishing pad and the chemical mechanical polishing composition; and polishing the at least one surface comprising the silicon dioxide film; wherein the silicon dioxide film is selected from the group consisting of Chemical vapor deposition (CVD) silicon dioxide film, Plasma Enhance CVD (PECVD) silicon dioxide film, High Density Deposition CVD(HDP) silicon dioxide film, spin on silicon dioxide film, and combinations thereof.
19. (canceled)
20. (canceled)
21. The method of claim 18; wherein the semiconductor substrate further has at least one surface comprising a silicon nitride film, and polishing rate of the silicon dioxide film vs polishing rate of the silicon nitride film is ≥1.
22. A system of chemical mechanical planarization (CMP) a semiconductor substrate having at least one surface comprising a silicon dioxide film, comprising a. the semiconductor substrate; a chemical mechanical planarization polishing composition comprising: ceria-coated inorganic oxide particles selected from the group consisting of ceria-coated colloidal silica, ceria-coated high purity colloidal silica, ceria-coated alumina, ceria-coated titania, ceria-coated zirconia particles and combinations thereof; a gelatin molecule comprising organic carboxylate functional groups providing negative charges and protonated organic amino groups providing the positive charges on the same molecule; a water soluble solvent selected from the group consisting of deionized (DI) water, distilled water, and alcoholic organic solvents; and optionally a biocide; and a pH adjuster; wherein the composition has a pH value of 3 to 10; and b. a polishing pad; wherein the at least one surface comprising the silicon dioxide film is in contact with the polishing pad and the chemical mechanical polishing composition; and the silicon dioxide film is selected from the group consisting of Chemical vapor deposition (CVD) silicon dioxide film, Plasma Enhance CVD (PECVD) silicon dioxide film, High Density Deposition CVD(HDP) silicon dioxide film, spin on silicon dioxide film, and combinations thereof.
23. (canceled)
24. (canceled)
25. The system of claim 22; wherein the semiconductor substrate further has at least one surface comprising a silicon nitride film, and polishing rate of the silicon dioxide film vs polishing rate of the silicon nitride film is ≥1.
26. The method of claim 18; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule further comprises organic amide functional groups, and 5-membered non-aromatic rings with one nitrogen atom as a hetero-atom.
27. The method of claim 18; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule is an organic gelatin molecule made from an animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof.
28. The method of claim 18; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule has a molecular structure of: ##STR00003##
29. The method of claim 18; wherein in the chemical mechanical planarization polishing composition; the biocide having an active ingredient of 5-chloro-2-methyl-4-isothiazolin-3-one or 2-methyl-4-isothiazolin-3-one; and the biocide having a concentration of from 0.0001 wt. % to 0.05 wt. %; and the pH adjuster selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof for acidic pH conditions; or selected from the group consisting of sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkyl ammonium hydroxide, organic quaternary_ammonium hydroxide compounds, organic amines, and combinations thereof for alkaline pH conditions; and the pH adjuster having a concentration of from 0 wt. % to 1 wt. %.
30. The method of claim 18; wherein the composition comprises ceria-coated colloidal silica particles as the ceria-coated inorganic oxide particles, the gelatin molecule made from animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof; and the pH value of the chemical mechanical planarization polishing composition is 4 to 9.
31. The system of claim 22; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule further comprises organic amide functional groups, and 5-membered non-aromatic rings with one nitrogen atom as a hetero-atom.
32. The system of claim 22; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule is an organic gelatin molecule made from an animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof.
33. The system of claim 22; wherein in the chemical mechanical planarization polishing composition; the gelatin molecule has a molecular structure of: ##STR00004##
34. The system of claim 22; wherein in the chemical mechanical planarization polishing composition; the biocide having an active ingredient of 5-chloro-2-methyl-4-isothiazolin-3-one or 2-methyl-4-isothiazolin-3-one; and the biocide having a concentration of from 0.0001 wt. % to 0.05 wt. %; and the pH adjuster selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof for acidic pH conditions; or selected from the group consisting of sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkyl ammonium hydroxide, organic quaternary_ammonium hydroxide compounds, organic amines, and combinations thereof for alkaline pH conditions; and the pH adjuster having a concentration of from 0 wt. % to 1 wt. %.
35. The system of claim 22, wherein the composition comprises ceria-coated colloidal silica particles as the ceria-coated inorganic oxide particles, the gelatin molecule made from animal skin selected from the group consisting of cold water fish skin, porcine skin, bovine skin, and combinations thereof; and the pH value of the chemical mechanical planarization polishing composition is 4 to 9.
Description
DETAILED DESCRIPTION OF THE INVENTION
[0031] In the global planarization of patterned STI structures, quickly removal of oxide capping layer with high oxide film removal rates is a key factor to be considered. Therefore, it is important to have STI CMP polishing compositions which can provide high oxide film removal rates when used for removing oxide capping layers effectively.
[0032] This invention relates to the Chemical mechanical polishing (CMP) compositions for Shallow Trench Isolation (STI) CMP applications.
[0033] More specifically, the disclosed chemical mechanical polishing (CMP) composition for Shallow Trench Isolation (STI) CMP applications have a unique combination of using ceria-coated inorganic oxide abrasive particles and a suitable chemical additive as an oxide film removal rate boosting agent.
[0034] The suitable chemical additive includes but is not limited to a gelatin molecule possessing negative and the positive charges on the same molecule and is either made from natural sources, from synthetic chemistry, and combinations thereof.
[0035] The use of the gelatin molecule as the chemical additive in the invented STI CMP polishing composition provides the benefits of achieving high oxide film removal rates, which are very useful for VNAND, ILD, and STI CMP applications demanding high oxide film removal rates for high throughput device fabrications.
[0036] In one aspect, there is provided a STI CMP polishing composition comprises:
ceria-coated inorganic oxide particles;
a gelatin molecule possessing negative and positive charges on the same molecule;
a water soluble solvent; and optionally
a biocide; and
a pH adjuster;
wherein the composition has a pH of 2 to 12, preferably 3 to 10, more preferably 4 to 9, and most preferably 4.5 to 7.5.
[0037] The ceria-coated inorganic oxide particles include, but are not limited to, ceria-coated colloidal silica, ceria-coated high purity colloidal silica, ceria-coated alumina, ceria-coated titania, ceria-coated zirconia, or any other ceria-coated metal oxide particles.
[0038] The mean particles sizes (MPS) of these ceria-coated inorganic oxide particles in the disclosed invention herein are ranged from 10 nm to 1,000 nm, 20 nm to 500 nm, 30 nm to 400 nm, 50 nm to 250 nm, or 100 nm to 200 nm. MPS refers to diameter of the particles and is measured using dynamic light scattering (DLS) technology.
[0039] The concentration of these ceria-coated inorganic oxide particles ranges from 0.01 wt. % to 20 wt. %, from 0.02 wt. % to 10 wt. %, from 0.005 wt. % to 5 wt. %, or from 0.01 wt. % to 3 wt. %.
[0040] The preferred ceria-coated inorganic oxide particles are ceria-coated colloidal silica particles.
[0041] The gelatin chemical additives comprise gelatin molecules bearing the negative and the positive charged on the same molecule.
[0042] The gelatin molecule can be organic or inorganic and made either from natural sources or from synthetic chemistry with negative and positive charges bearing on the same molecule.
[0043] The gelatin molecule for example, comprises organic carboxylate functional groups which provide the negative charges and the protonated organic amino groups which provide the positive charges. In addition, the gelatin molecule can also contain the organic amide functional groups, 5-membered non-aromatic rings with one nitrogen atom as a hetero-atom.
[0044] For example, the organic gelatin molecule is made from animal skin, such as, cold water fish skin, porcine skin, and bovine skin.
[0045] Gelatin from cold water fish skin (G7041), bovine skin (G9381, G9382, G6650), and porcine skin (G1890) can be purchased from Sigma-Aldrich, St. Louis, Mo.
[0046] As an example, the molecular structure of gelatin made from cold water fish skin is shown below:
##STR00001##
[0047] The water-soluble solvent includes but is not limited to deionized (DI) water, distilled water, and alcoholic organic solvents.
[0048] The concentration of gelatin ranges from 0.0001 wt. % to 5 wt. %, 0.0005 wt. % to 2 wt. %, 0.001 wt. % to 1 wt. %, 0.002 wt. % to 0.5 wt. %, 0.0025 wt. % to 0.25 wt. %, or 0.003 wt. % to 0.1 wt. %.
[0049] The preferred water soluble solvent is DI water.
[0050] The STI CMP composition may contain the biocide from 0.0001 wt. % to 0.05 wt. %; from 0.0005 wt. % to 0.025 wt. %, or 0.001 wt. % to 0.01 wt. %.
[0051] The biocide includes, but is not limited to, Kathon™, Kathon™ CG/ICP II, from Dupont/Dow Chemical Co. Bioban from Dupont/Dow Chemical Co. They have active ingredients of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one.
[0052] The STI CMP composition may contain the pH adjuster.
[0053] An acidic or basic pH adjuster can be used to adjust the STI polishing compositions to the optimized pH value.
[0054] The pH adjuster includes, but is not limited to nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof.
[0055] The pH adjuster also includes a basic pH adjusting agent, such as sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkyl ammonium hydroxide, organic quaternary ammonium hydroxide compounds, organic amines, and other chemical reagents that can be used to adjust pH towards the more alkaline direction.
[0056] The STI CMP composition contains 0 wt. % to 1 wt. %; 0.01 wt. % to 0.5 wt. %; or 0.1 wt. % to 0.25 wt. % of the pH adjuster.
[0057] In another aspect, there is provided a method of chemical mechanical planarization (CMP) a substrate having at least one surface comprising a silicon dioxide film using the STI CMP polishing composition described above in Shallow Trench Isolation (STI) process.
[0058] In another aspect, there is provided a system of chemical mechanical polishing (CMP) a substrate having at least one surface comprising a silicon dioxide film using the STI CMP polishing composition described above in Shallow Trench Isolation (STI) process.
[0059] The polished silicon dioxide film can be formed by Chemical vapor deposition (CVD) referred to as a CVD silicon dioxide film, Plasma Enhance CVD (PECVD) referred to as a PECVD silicon dioxide film, High Density Deposition CVD (HDP) referred to as a high density silicon dioxide film, or a spin on referred to as a spin on silicon dioxide film.
[0060] The substrate disclosed above can further comprises a silicon nitride surface.
[0061] In another aspect, there is provided a method of chemical mechanical planarization (CMP) a substrate having at least one surface comprising a silicon dioxide film using the STI CMP polishing composition described above in Shallow Trench Isolation (STI) process. The polished silicon dioxide film can be CVD silicon dioxide, PECVD silicon dioxide, High density silicon dioxide, or a Spin on silicon dioxide film.
[0062] The following non-limiting examples are presented to further illustrate the present invention.
CMP Methodology
[0063] In the examples presented below, CMP experiments were run using the procedures and experimental conditions given below.
Parameters
[0064] Å or A: angstrom(s)—a unit of length
[0065] BP: back pressure, in psi units
[0066] CMP: chemical mechanical planarization or chemical mechanical polishing
[0067] CS: carrier speed
[0068] DF: Down force: pressure applied during CMP, unit: psi
[0069] min: minute(s)
[0070] ml: milliliter(s)
[0071] mV: millivolt(s)
[0072] psi: pounds per square inch
[0073] PS: platen rotational speed of polishing tool, in rpm (revolution(s) per minute)
[0074] SF: composition flow, ml/min
[0075] Wt. %: weight percentage (of a listed component)
[0076] HDP: high density plasma deposited TEOS
[0077] TEOS: tetraethyl orthosilicate
[0078] TEOS or HDP Removal Rates: Measured TEOS or HDP removal rate at a given down pressure. The down pressure of the CMP tool was 3.0 psi or 4.0 psi in the examples; listed below.
[0079] SiN Removal Rates: Measured SiN removal rate at a given down pressure. The down pressure of the CMP tool was 3.0 psi or 4.0 psi in the examples listed.
Polishing Experiments
[0080] The CMP tool that was used is a 200 mm Mirra, or 300 mm Reflexion manufactured by Applied Materials, 3050 Boweres Avenue, Santa Clara, Calif., 95054. An IC1000 pad supplied by DOW, Inc, 451 Bellevue Rd., Newark, Del. 19713 was used on platen 1 for blanket and pattern wafer studies.
[0081] Polishing Pad: Polishing pad, IC1010, IC1000 and other pads were used during CMP, supplied by DOW, Inc.
[0082] The IC1010 pad supplied by DOW, Inc or other pad was broken in by conditioning the pad for 18 mins. At 7 lbs. down force on the conditioner. To qualify the tool settings and the pad break-in two tungsten monitors and two TEOS monitors were polished with Versum® STI2305 composition, supplied by Versum Materials Inc. at baseline conditions.
[0083] Ceria-coated Silica particles (with varied sizes) were supplied by JGC C&C Ltd. in Japan. The particles are made by the methods described in JP2013119131, JP2013133255, and WO2016159167; and the properties of the particles are also described in US20160200944A1; the disclosures are hereby incorporated by reference.
[0084] The MPS of the ceria-coated silica composite particles used in the examples were around 110 nm to around 125 nm. The ceria nano-particles coated on the surface of colloidal silica particles was >10 nm or >13 nm.
[0085] Gelatin made from cold water fish skin (G7041) was supplied by Sigma-Aldrich, St. Louis, Mo.
[0086] In blanket wafer studies, oxide blanket wafers, and SiN blanket wafers were polished at baseline conditions. The tool baseline conditions were: table speed: 87 rpm, head speed: 93 rpm, membrane pressure; 3.0 psi DF or 4.0 psi DF, composition flow; 200 ml/min. The polishing pad used for testing was IC1010 pad which was supplied by Dow Chemicals.
[0087] Polishing experiments were conducted using PECVD or LECVD or HD TEOS wafers. These blanket wafers were purchased from Silicon Valley Microelectronics, 2985 Kifer Rd., Santa Clara, Calif. 95051.
[0088] Deionized water was used as the solvent in the compositions in the working examples.
[0089] The composition was used in polishing experiments on patterned wafers (MIT860) supplied by SWK Associates, Inc. 2920 Scott Blvd. Santa Clara, Calif. 95054). These wafers were measured on the Veeco VX300 profiler/AFM instrument. The 3 different sized pitch structures were used for oxide dishing measurement. The wafer was measured at center, middle, and edge die positions.
WORKING EXAMPLES
Example 1
[0090] In Example 1, the polishing compositions used for oxide polishing were shown in Table 1.
[0091] The reference sample was made by using 0.2 wt. % ceria-coated silica particles plus very low concentration ranging from 0.0001 wt. % to 0.05 wt. % of biocide, and DI water with finished pH at 5.35.
[0092] The polishing compositions were prepared by adding 0.0083 wt. % (or 83 ppm) gelatin made from cold water fish skin into the reference sample with final pH at 5.35.
[0093] The polishing step conditions used were Dow's IC1010 pad at 3.0 psi DF with table/head speed at 87/93 rpm and ex-situ conditioning.
[0094] The removal rates (RR at Å/min) for different films were tested. The effects of chemical additive gelatin made from cold water fish skin on the film removal rates were observed and listed in Table 1 and depicted in
TABLE-US-00001 TABLE 1 Effects of Gelatin made from Cold Water Fish Skin on Film RR (Å /min.) TEOS PECVD RR HDP RR SiN RR Composition (A/min.) (A/min.) (A/min.) 0.2% Ceria-coated silica pH 5.35 2847 1994 375 0.2% Ceria-coated Silica + 4564 4662 1296 0.0083% Gelatin from cold water (+60%) (+134%) (+246%) fish skin, pH 5.35
[0095] As the results shown in Table 1 and
Example 2
[0096] In Example 2, the polishing compositions used for polishing were shown in Table 2.
[0097] The reference sample was made by using 1.0 wt. % ceria-coated silica particles plus very low concentration ranging from 0.0001 wt. % to 0.05 wt. % of biocide, and DI water.
[0098] The polishing compositions were prepared by adding different concentrations 0.0083 wt. % (83 ppm), 0.0415 wt. % (415 ppm), or 0.083 wt. % (830 ppm), respectively of gelatin made from cold water fish skin into the reference sample.
[0099] The reference sample and polishing compositions had same pH values at around 7.0.
[0100] The effects of using gelatin made from cold water fish skin on the oxide and SiN film removal rates were tested at 3.0 psi DF, and the results were listed in Table 2 and depicted in
TABLE-US-00002 TABLE 2 Effects of Gelatin made from Fish Skin on Oxide and SiN Film TEOS TEOS RR PECVD SiN RR RR (A/min.) SiN RR (A/min.) Compositions (A/min.) Change % (A/min.) Change % 1% Ceria-coated 6296 230 Silica 1% Ceria-coated 6817 (+) 8.3% 355 (+) 54.3% Silica + 83 ppm Gelatin 1% Ceria-coated 10735 (+) 70.5% 1386 (+) 502.3% Silica + 415 ppm Gelatin 1% Ceria-coated 9888 (+) 57% 2037 (+) 785.6% Silica + 830 ppm Gelatin
[0101] As the results shown in Table 2 and
Example 3
[0102] In Example 3, the reference sample and the polishing compositions were the same as used in Example 2.
[0103] The effects of gelatin made from cold water fish skin on the oxide and SiN film removal rates were tested at 4.0 psi DF, and the results were listed in Table 3 and depicted in
TABLE-US-00003 TABLE 3 Effects of Gelatin made from Fish Skin on Oxide and SiN Film TEOS TEOS RR PECVD SiN RR RR (A/min.) SiN RR (A/min.) Compositions (A/min.) Change % (A/min.) Change % 1% Ceria-coated 7359 892 Silica 1% Ceria-coated 8004 (+) 9.5% 1344 (+) 50.7% Silica + 83 ppm Gelatin 1% Ceria-coated 12561 (+) 70.7% 2413 (+) 170.5% Silica + 415 ppm Gelatin 1% Ceria-coated 12332 (+) 67.6% 3289 (+) 268.7% Silica + 830 ppm Gelatin
[0104] As the results shown in Table 3 and
[0105] The embodiments of this invention listed above, including the working example, are exemplary of numerous embodiments that may be made of this invention. It is contemplated that numerous other configurations of the process may be used, and the materials used in the process may be elected from numerous materials other than those specifically disclosed.