Prosecution Insights
Last updated: April 19, 2026
Application No. 17/435,927

SILICON NITRIDE ETCHING LIQUID COMPOSITION

Non-Final OA §103§112
Filed
Sep 02, 2021
Examiner
AHMED, SHAMIM
Art Unit
1713
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Kanto Kagaku Kabushiki Kaisha
OA Round
1 (Non-Final)
78%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
99%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allow Rate
938 granted / 1197 resolved
+13.4% vs TC avg
Strong +22% interview lift
Without
With
+22.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
48 currently pending
Career history
1245
Total Applications
across all art units

Statute-Specific Performance

§101
0.4%
-39.6% vs TC avg
§103
54.4%
+14.4% vs TC avg
§102
13.5%
-26.5% vs TC avg
§112
18.3%
-21.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1197 resolved cases

Office Action

§103 §112
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 . Election/Restrictions Applicant's election with traverse of Group II, claim 12, in the reply filed on 11/28/2025 is acknowledged. The traversal is on the ground(s) that searching and examining all the claims would not be a serious or undue burden on the office. This is not found persuasive because they (Group I-III) lack of unity in view of the JP-312 (explained in the restriction requirement of dated 10/10/2025), not for the serious/undue search burden. The requirement is still deemed proper and is therefore made FINAL. However, applicants cancel the claims 1-11 and 13 (non-elected) and additionally, added new claims 14-20, which encompasses the elected invention. Claim Rejections - 35 USC § 112 The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. Claims 12 and 14-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Claim 12 recites the limitation "the etching liquid" in line 4. There is insufficient antecedent basis for this limitation in the claim. Claims 14-19 are directly or indirectly depends on claim 12; and therefore, also include the limitation. Claim 20 recites the limitation "the etching liquid composition" in 3. There is insufficient antecedent basis for this limitation in the claim. Claim Rejections - 35 USC § 103 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 (i.e., changing from AIA to pre-AIA ) 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. 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, 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. Claim(s) 12,14-15,18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al (US 10,689,572). Regarding claim 12, Lee et al disclose a semiconductor manufacturing process, wherein a silicon oxide film (SiO.sub.2) and a silicon nitride film (SiNx), which are representative insulating films, are stacked individually or stacked into one or more films in an alternate sequence for forming a three-dimensional NAND flash memory gate (col.1, lines 26-38). Lee et al disclose that during the above-mentioned process, an etchant composition for selective etching silicon nitride film, compared to a silicon oxide film (abstract), in which the etchant comprises phosphoric acid, a silicon compound and water (col.2, lines 35-44), wherein the silicon compound is selected from among hexafluorosilicate, aluminum silicate, calcium silicate, tetraethylorthosilicate, tetraethyl orthosilicate, silicate, sodium fluorosilicate, sodium hexafluorosilicate, 3-aminopropyl trimethoxysilane, aminoethyl-aminotrimethoxysilane, and dichlorosilane (col.5, lines 50-56); and aforesaid “3-aminopropyl trimethoxysilane” encompasses the silane coupling agent represented by chemical formula 1 because the chemical structure of 3-aminopropyl trimethoxysilane is provided below (source Google). PNG media_image1.png 200 200 media_image1.png Greyscale Examiner pointed out that nowhere in the disclosure of Lee et al disclose that the etching composition comprises an ammonium ions and therefore, meet the limitation of the etching composition does not comprise ammonium ions. Lee et al fail to explicitly teach the 3-D memory cell having silicon dioxide pattern, in which collapse of the silicon dioxide pattern is restricted. However, Lee et al disclose that etchant composition with a high selectivity is provided, which etches a silicon nitride film with a selectivity of 2000:1 or higher between the silicon nitride film and a silicon oxide film which are in a stack structure, and minimizes damage to the silicon oxide film and etching rate, and does not cause re-growth of the silicon oxide film over the process time (col.2, lines 27-33). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to easily appreciate that such teaching above obviously restrict the collapse of the silicon oxide pattern as taught by Lee et al (see also col.1, lines 53-58) because the etching solution and the material to be etched are similar in nature and expected to have the same result, namely the collapse of the silicon oxide pattern is restricted as claimed. Regarding claims 14-16 and 18, Lee et al disclose above the silicon compound is 3-aminopropyl trimethoxysilane (col.5, lines 50-56); and the compound having at least two of R1, R2 and R3 are alkoxy groups (-OR) with regards to claim 15 (see the above chemical structure of 3-aminopropyl trimethoxysilane), which also reads on the silane coupling agent comprises an amino group (-NH2) as of claim 16. Regarding claim 19, Lee et al disclose that the etchant composition with a high selectivity to a silicon nitride film, which may include, based on total weight, 60 to 85 wt % of phosphoric acid, and 0.005 to 1 wt % of the silicone compound, with the remainder being water (col.3, lines 37-43), the silicon compound (resemble as the clamed silane coupling agent); and aforesaid teaching overlaps the claimed range of phosphoric acid of 60 to 95 wt% and also overlaps the claimed range of 0.01 to 10 wt% of a silane coupling agent and overlapping ranges are prima facie obvious, MPEP 2144.05. Regarding claim 20, Lee et al disclose a semiconductor manufacturing process, wherein a silicon oxide film (SiO.sub.2) and a silicon nitride film (SiNx), which are representative insulating films, are stacked individually or stacked into one or more films in an alternate sequence for forming a three-dimensional NAND flash memory gate (col.1, lines 26-38). Lee et al disclose that during the above-mentioned process, an etchant composition for selective etching silicon nitride film, compared to a silicon oxide film (abstract), in which the etchant comprises phosphoric acid, a silicon compound and water (col.2, lines 35-44), wherein the silicon compound is selected from among hexafluorosilicate, aluminum silicate, calcium silicate, tetraethylorthosilicate, tetraethyl orthosilicate, silicate, sodium fluorosilicate, sodium hexafluorosilicate, 3-aminopropyl trimethoxysilane, aminoethyl-aminotrimethoxysilane, and dichlorosilane. The silicon compound is contained in an amount of 0.005 to 1 wt% (col.5, lines 50-56); and aforesaid “3-aminopropyl trimethoxysilane” encompasses the silane coupling agent represented by chemical formula 1 because the chemical structure of 3-aminopropyl trimethoxysilane is provided above. Lee et al fail to explicitly teach collapse of the silicon dioxide pattern is restricted. However, Lee et al disclose that etchant composition with a high selectivity is provided, which etches a silicon nitride film with a selectivity of 2000:1 or higher between the silicon nitride film and a silicon oxide film which are in a stack structure, and minimizes damage to the silicon oxide film and etching rate, and does not cause re-growth of the silicon oxide film over the process time (col.2, lines 27-33). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to easily appreciate that such teaching above obviously restrict the collapse of the silicon oxide pattern as taught by Lee et al (see also col.1, lines 53-58) because the etching solution and the material to be etched are similar in nature and expected to have the same result, namely the collapse of the silicon oxide pattern is restricted as claimed. Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al (US 10,689,572) as applied to claims 12 and 14 above, and further in view of KR 10-20170059170 A (herein after, KR’170; provided with the IDS dated 9/2/2021; Machine translation is provided). Lee et al disclose above for the claims 12 and 14 But fail to disclose the silane coupling agent comprises a phenyl group in the R4 of the formula 1. However, in the same field of endeavor, KR’170 disclose a process of selectively etching silicon nitride in presence of silicon oxide during making a 3D NAND flash memory device [0024],[0031], using an etchant solution comprises phosphoric acid, water and silicon -based compound [0073], [0075] including N-phenylaminomethyl (tri-methoxy)silane ([0112] in the machine translation); and aforesaid teaching appears to teach the silane coupling agent comprises phenyl group in R4 of the formula 1. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ KR’170's teaching of introducing the silane coupling agent (silicon -based compound) into the teaching of Lee et al for effective etching the silicon nitride with selectivity as suggested by KR’170. Additionally, it would have been a simple substitution of known materials in the art for predictable result. Conclusion The prior art made of record, listed in the PTO-892 and not relied upon is considered pertinent to applicant's disclosure. Cooper et al (US 2019/0074188) disclose an etching or removal of silicon nitride from a substrate by etching can preferably be performed in a manner that does not damage or disrupt other exposed or covered features of a microelectronic device, using an etching solution comprises phosphoric acid, water, an amino alkoxy silane (see, abstract, [0005],[0008],[0044], [0063]; Figure 1): PNG media_image2.png 308 712 media_image2.png Greyscale NISHITANI et al (US 2015/0091075) disclose a process of making a nonvolatile semiconductor memory device (abstract); and a technique for suppressing collapse of the laminated patterns [0005],[0018]. Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHAMIM AHMED whose telephone number is (571)272-1457. The examiner can normally be reached M-TH (8-5:30pm). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Joshua Allen can be reached at 571-270-3176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. SHAMIM AHMED Primary Examiner Art Unit 1713 /SHAMIM AHMED/ Primary Examiner, Art Unit 1713
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Prosecution Timeline

Sep 02, 2021
Application Filed
Feb 18, 2026
Non-Final Rejection — §103, §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
78%
Grant Probability
99%
With Interview (+22.1%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 1197 resolved cases by this examiner. Grant probability derived from career allow rate.

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