DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office Action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on January 5, 2026 has been entered.
Response to Amendments/Arguments
Amendments made to claims 1-2, 8, 10, 21 and 28, the addition of claims 29-31, and the cancelation of claims 3, 13, 15-20, 22, 25 and 27, as filed on January 5, 2026, are acknowledged.
The Applicant’s Statement Regarding Substance of Interview, see Remarks filed on January 5, 2026, makes a conclusive statement of “[t]he Examiner agreed that the proposed amendments, substantially included in this response, overcome the applied references”. However, this statement is not accurate, see the Examiner Interview Summary Record mailed on December 16, 2025 for detailed discussion of the interview. No agreement was achieved during the interview.
Applicant's arguments, see Remarks filed on January 5, 2026 with respect to rejections based on Wang reference have been fully considered but they are not persuasive.
The Applicant argues that “WANG fails to disclose a chemical etchant defined by a volumetric dilution ratio, such as potassium hydroxide being diluted in deionized water to approximately 30% of a total volume of the chemical etchant, as expressly required by amended claim 21. A molar concentration (mol/L) specifies the amount of solute per unit volume of solution, whereas a volumetric dilution ratio specifies the relative volumes of components used to form the solution. These are different parameters, and WANG does not disclose preparing or using a KOH etchant based on a volumetric percentage”. However, Wang discloses wherein the surface of the semiconductor substrate is chemically etched using a solution in which potassium hydroxide (KOH) is present at a concentration of greater than 3mol/L (paragraph n0081, the molar mass of KOH is 56g/mol, the density of KOH is 2g/ml; therefore, the concentration of KOH is greater than 84ml/L), which encompasses the concentration recited in the instant claim. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I). Wang is silent about the solvent for the solution being deionized water. However, deionized water is a well-known solvent for a KOH solution.
Applicant’s arguments with respect to rejections to amended claims based on references other than Wang have been considered but are moot because the arguments do not apply to new ground(s) of rejection in this Office Action necessitated by the amendments made to the claims.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office Action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2, 4-7, 21, 23-24, 26, 29 and 31 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka et al. (US20200114488) in view of Sato et al. (“Characterization of orientation-dependent etching properties of single-crystal silicon: effects of KOH concentration”, Sensors and Actuators A, vol. 64, year 1998, pages 87-93).
Regarding claim 1, Tanaka discloses a method (abstract), comprising: positioning a semiconductor substrate on a platen in a processing chamber of a substrate grinding tool (paragraph 0029 and Fig. 2); and performing, using the substrate grinding tool, a grinding operation to remove material from the semiconductor substrate to reduce a thickness of the semiconductor substrate, wherein a chemical etchant dispensed onto a surface of the semiconductor substrate during the grinding operation to reduce a surface roughness of the semiconductor substrate, and wherein a temperature of the chemical etchant satisfies a temperature threshold (paragraphs 0034-0035). Tanaka is silent about the concentration of the KOH solution; however, Tanaka discloses that the aqueous KOH solution is used in polishing silicon wafer (paragraphs 0033-0034). In addition, Sato teaches that KOH concentration is a result-effective variable impacting silicon etch profile (section 5, page 92). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to optimize the concentration of KOH (a result-effective variable) in the method of Tanaka to achieve desirable etch profile as taught by Sato, with a reasonable expectation of success. Additionally, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05 II.
Regarding claim 2, Tanaka discloses wherein the semiconductor substrate comprises a silicon (Si) substrate (paragraph 0024).
Regarding claim 4, Tanaka discloses wherein the chemical etchant is dispensed onto the surface of the semiconductor substrate after a grinding device of the substrate grinding tool mechanically grinds the surface of the semiconductor substrate during the grinding operation (aqueous alkaline solution used in the second polishing step reads on a chemical etchant, claim 4).
Regarding claim 5, Tanaka is silent about wherein a pH of the chemical etchant is included in a range of approximately 10 to approximately 14. However, Tanaka discloses that the chemical etchant is an aqueous alkaline solution (claim 4), indicating that the pH of the solution is greater than 7, which encompasses the range recite din the instant claim. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I).
Regarding claim 6, Tanaka discloses wherein the chemical etchant is dispensed onto the surface of the semiconductor substrate while a grinding device of the substrate grinding tool mechanically grinds the surface of the semiconductor substrate during the grinding operation (paragraph 0029 and Fig. 2).
Regarding claim 7, Tanaka discloses wherein the semiconductor substrate is rotated on the platen while the chemical etchant is dispensed onto the surface of the semiconductor substrate to disperse the chemical etchant across the surface of the semiconductor substrate (paragraphs 0029 and 0038, Fig. 2).
Regarding claim 21, Tanaka discloses a method (abstract), comprising: mechanically removing a material from a semiconductor substrate that is in a processing chamber (claim 4 and Fig. 2) and chemically etching a surface of the semiconductor substrate (aqueous alkaline solution etches silicon, claim 4). Tanaka is silent about the concentration of the KOH solution; however, Tanaka discloses that the aqueous KOH solution is used in polishing silicon wafer (paragraphs 0033-0034). In addition, Sato teaches that KOH concentration is a result-effective variable impacting silicon etch profile (section 5, page 92). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to optimize the concentration of KOH (a result-effective variable) in the method of Tanaka to achieve desirable etch profile as taught by Sato, with a reasonable expectation of success. Additionally, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05 II.
Regarding claim 23, Tanaka discloses wherein the surface of the semiconductor substrate is chemically etched during a rotation of a platen supporting the semiconductor substrate (adjusting the flow rate of the polishing agent and the rotation rate of the polishing head, paragraph 0038).
Regarding claim 24, Tanaka discloses wherein the surface of the semiconductor substrate is chemically etched while the material from the semiconductor substrate is removed (claim 4).
Regarding claim 26, Tanaka discloses wherein the surface of the semiconductor substrate is chemically etched while and after the material from the semiconductor substrate is removed (claim 4).
Regarding claim 29, Tanaka is silent about receiving one or more signals to cause the grinding operation; however, this is an inherent feature of a grinding operation.
Regarding claim 31, Tanaka discloses wherein the semiconductor substrate is supported on a platen, and wherein the platen and the semiconductor substrate are rotated in a same direction during chemical etching (a polishing head reads on a platen, the semiconductor substrate is held by the polishing head, paragraphs 0029 and 0038).
Claims 8 -14 and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Shimomura et al. (US5643406) in view of Sato et al. (“Characterization of orientation-dependent etching properties of single-crystal silicon: effects of KOH concentration”, Sensors and Actuators A, vol. 64, year 1998, pages 87-93).
Regarding claim 8, Shimomura discloses a method (abstract), positioning a semiconductor substrate on a platen in a processing chamber of a substrate grinding tool (lines 43-53, column 5 and Fig. 10); performing, using a grinding device of the substrate grinding tool, a first part of a grinding operation to remove material from the semiconductor substrate (polishing using a slurry containing polishing particles reads on a grinding operation, claim 1 and Fig. 10); and performing, using a chemical etchant dispensed onto a surface of the semiconductor substrate in the processing chamber, a second part of the grinding operation after the first part of the grinding operation (alkaline ionized water reads on a chemical etchant, claims 1-2), wherein the chemical etchant is dispensed onto the surface of the semiconductor substrate at a temperature that is included in a particular temperature range such that an etch rate of the chemical etchant, for etching the surface of the semiconductor substrate, satisfies an etch rate threshold (lines 59-66, column 7 and Fig. 10). Shimomura is silent about the concentration of the KOH solution; however, Shimomura discloses that the aqueous KOH solution is used in polishing silicon (claim 7; lines 66-67, column 2). In addition, Sato teaches that KOH concentration is a result-effective variable impacting silicon etch profile (section 5, page 92). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to optimize the concentration of KOH (a result-effective variable) in the method of Shimomura to achieve desirable etch profile as taught by Sato, with a reasonable expectation of success. Additionally, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05 II.
Regarding claim 9, Shimomura does not expressly disclose wherein the particular temperature range comprises approximately 40 degrees Celsius to approximately 100 degrees Celsius. However, Shmomura teaches that the temperature of the chemical etchant (ionized water) can be controlled to adjust the polishing rate (lines 59-66, column 7). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to optimize the temperature range (a result-effective variable) to achieve desirable polishing rate as taught by Shimomura. Additionally, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05 II.
Regarding claim 10, Shimomura discloses wherein the semiconductor substrate comprises a silicon (Si) substrate (claim 7).
Regarding claim 11, Shimomura discloses wherein performing the second part of the grinding operation comprises: performing the second part of the grinding operation using a combination of the chemical etchant and the grinding device (claim 1 and Fig. 10).
Regarding claim 12, Shimomura discloses wherein performing the second part of the grinding operation comprises: performing the second part of the grinding operation to reduce a surface roughness of the surface of the semiconductor substrate (claim 1 and Fig. 10).
Regarding claim 14, Shimomura discloses wherein the semiconductor substrate is rotated on the platen while the chemical etchant is dispensed onto the surface of the semiconductor substrate to disperse the chemical etchant across the surface of the semiconductor substrate (claim 1 and Fig. 5).
Regarding claim 30, Shimomura discloses wherein, during the first part of the grinding operation, the material is removed to achieve a threshold thickness for the semiconductor substrate (a desired thickness to be removed in the polishing step reads on a a threshold thickness, claim 1).
Claims 21, 24, 26 and 28 are rejected under 35 U.S.C. 103 as being obvious over Wang et al. (CN114695081, a machine-translated English version is used).
Regarding claim 21, Wang discloses a method, comprising: mechanically removing a material from a semiconductor substrate that is in a processing chamber (paragraphs n0051 and n0068); and chemically etching, using a chemical etchant comprising potassium hydroxide (KOH) at a concentration of greater than 3mol/L (paragraph n0081), a surface of the semiconductor substrate (paragraph n0072). The concentration of KOH disclosed by Wang encompasses the concentration recited in the instant claim (paragraph n0081, the molar mass of KOH is 56g/mol, the density of KOH is 2g/ml; therefore, the concentration of KOH is greater than 84ml/L, i.e. greater than 8% of total volume of the chemical etchant). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I). Wang is silent about the solvent for the solution being deionized water. However, deionized water is a well-known solvent for a KOH solution.
Regarding claim 24, Wang discloses wherein the surface of the semiconductor substrate is chemically etched while the material from the semiconductor substrate is removed (paragraph n0085).
Regarding claim 26, Wang discloses wherein the surface of the semiconductor substrate is chemically etched while and after the material from the semiconductor substrate is removed (paragraph n0085).
Regarding claim 28, Wang fails to discloses wherein the surface of the semiconductor substrate is chemically etched for approximately 2 minutes. However, Wang teaches that the chemically etching step is carried out to remove certain thickness of the substrate as needed to remove the damaged layer (paragraph n0085). Therefore, it would have been obvious to one of ordinary skill, in the art before the effective filing date of the claimed invention, to optimize the chemical etching time (a result-effective variable, etching time = removal thickness/etch rate) to achieve desirable removal thickness of the substrate. Additionally, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable range by routine experimentation and there is no evidence of the criticality of the claimed range. See MPEP 2144.05 II.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIONG-PING LU whose telephone number is (571) 270-1135. The examiner can normally be reached on M-F: 9:00am – 5:00pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Joshua L Allen, can be reached at telephone number (571)270-3176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JIONG-PING LU/
Primary Examiner, Art Unit 1713