Prosecution Insights
Last updated: April 19, 2026
Application No. 18/191,652

SILICON ETCHANT AND SILICON ETCHING METHOD

Final Rejection §103
Filed
Mar 28, 2023
Examiner
ALANKO, ANITA KAREN
Art Unit
1713
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Tokyo Ohka Kogyo Co., Ltd.
OA Round
4 (Final)
69%
Grant Probability
Favorable
5-6
OA Rounds
3y 1m
To Grant
52%
With Interview

Examiner Intelligence

Grants 69% — above average
69%
Career Allow Rate
470 granted / 677 resolved
+4.4% vs TC avg
Minimal -17% lift
Without
With
+-17.2%
Interview Lift
resolved cases with interview
Typical timeline
3y 1m
Avg Prosecution
36 currently pending
Career history
713
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
45.1%
+5.1% vs TC avg
§102
20.7%
-19.3% vs TC avg
§112
20.0%
-20.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 677 resolved cases

Office Action

§103
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 . Claim Rejections - 35 USC § 103 The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. Claims 1, 4 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Walker et al (US 7,365,045 B2) in view of Kamimura (US 2023/0099612 A1). As to claims 1 and 4, Walker discloses a composition consisting of: a component (A): a quaternary ammonium hydroxide (col.4, lines 13-14, tetramethyl ammonium hydroxide, col.4, lines 39-40); a component (B): alkanolamine (col.4, lines 14, 42-45); a component (C): water (col.4, line 15), wherein a content of the component (C) is 86 wt%, and a content of component (B) is 9.0 wt% (monoethanolamine 9.0 wt%, tetramethyl ammonium hydroxide 5 wt%, balance water (col.12, lines 24-26)), which are points within the ranges cited. A specific example in the prior art which is within a claimed range anticipates the range. MPEP 2131.03. The preamble is given little patentable weight. The composition of Walker is capable of serving as a silicon etchant composition. As to amended claim 1, Walker discloses to include an amine compound comprising an alkanolamine, not 1,3-propanediamine. Kamimura teaches treatment liquids that include quaternary ammonium compounds [0198], water [0111], but that also include amine compounds [0164]. Kamimura teaches that examples of amine compounds include an alkanol amine (“amino alcohol”) or an aliphatic polyamine compound [0169]. Kamimura teaches that a useful aliphatic polyamine compound is the cited 1,3-propanediamine [0190]. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to include 1,3-propanediamine in place of the alkanol amine compound in the composition of Walker because Kamimura teaches that it is a useful alternative form of amine, it is a functionally equivalent amine compound, and such is expected to give the predictable result of a useful silicon etchant. As to the content of the amine compound, Kamimura teaches that the amine compound content can range from 0.01% to 20% by mass [0196], which is expected to overlap with the cited range. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to provide the cited content of component B in the modified composition of Walker because Walker already suggests a point within the cited range, Kamimura teaches points in the cited range are useful, and because the concentration can be optimized for best results. MPEP 2144.05, II. A. As to claim 7, Walker discloses that component A is 0.02-13.5 wt% (col.14, lines 24-25), which overlaps with the inferred cited range. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to provide the cited content of component A in the modified composition of Walker because Walker already suggests a range overlapping with the inferred claimed range, and because the concentration can be optimized for best results. MPEP 2144.05, II. A. Claims 13, 15-16 and 18-19 are rejected under 35 U.S.C. 103 as being unpatentable over Roh et al (KR-20200086180A) in view of Kamimura (US 2023/0099612 A1). As to claims 13 and 15, Roh discloses a silicon etchant (abstract, page 3) consisting of: a component (A): a quaternary ammonium hydroxide (abstract, page 3, see marked-up version of English translation; A-1, tetramethylammonium hydroxide, page 9; page 12, claim 1); a component (B): polyamine (C-4, diethylenetriamine, page 9) or alkanolamine (abstract, pages 3-4; page 12, claim 1; C-2, 2-amino-1-butanol, page 9); a component (C): water (abstract; page 12, claim 1); and a surfactant (abstract, pages 4-5; B-2, polyoxyethylene phenyl ether, B-3 polyoxyethylene beta-naphthly ether, page 9; page 12, claim 1) wherein a content of the component (C) is, in examples 8 and 31 of Table 1 [0086], Example 8 quaternary ammonium hydroxide, A-1 – 3.2 wt% alkanol amine, Roh’s C-2 – 11.4% water, 88.27% surfactant, Roh’s B-3 – 0.13 wt% Example 31 quaternary ammonium hydroxide, A-1 – 15.6 wt% polyamine, Roh’s C-4 – 12.0 wt% water, 72.32% surfactant, Roh’s B2 – 0.08 wt% PNG media_image1.png 51 671 media_image1.png Greyscale PNG media_image2.png 41 669 media_image2.png Greyscale Examples 8 & 31 of Table 1 Example 31, which includes the polyamine, provides water content less than the cited range, 72.32% compared to 77.62% or more. Roh discloses that the content of components A and B can vary widely (1-20 wt% quarternary ammonium hydroxide, 1-30 wt% amine). Other examples provide 3.2% of the ammonium hydroxide (Examples 7-8), or 1% of component B (example 22). These other examples, while not for a polyamine, provide water content squarely within the cited range, and together with the wide ranges disclose the cited range. As to amended claim 13, Roh discloses that the polyamine, diethylenetriamine (DETA), may be included (page 9, example C-4) in the composition. Roh fails to disclose the specific structure of other related polyamines. Kamimura teaches that in compositions including polyamines, useful alternative alkylenediamines for DETA include 1,3-propanediamine [0190] (as cited in claim 3) or 1,4-propanediamine [0190]. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to include 1,3-propanediamine as the amine in the composition of Roh because Kamimura teaches that it is a useful alternative form of amine, is a functionally equivalent amine compound, and is expected to give the predictable result of a useful silicon etchant. As to the content of the amine compound, Kamimura teaches that the amine compound content can range from 0.01% to 20% by mass [0196], which is expected to overlap with the cited range. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to provide the cited content of components B and C in the modified composition of Roh because Roh already overlapping ranges as described above, Kamimura teaches overlapping ranges that are useful, and because the concentration can be optimized for best results. MPEP 2144.05, II. A. As to claim 15, see the rejection of claim 13. As to claim 16, Roh discloses component (A) at 1-20% by weight (page 3), which overlaps with the cited range. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to provide the cited content of component A in the modified composition of Roh because Roh already overlapping ranges as described above, and because the concentration can be optimized for best results. MPEP 2144.05, II. A. As to claim 18, Roh discloses component (D) at 0.01-0.2% by weight (page 5), which is within the cited range. As to claim 19, Roh only teaches a nonionic surfactant, not an anionic surfactant (see rejection of claim 13). Kamimura teaches that the surfactant in the composition is not particularly limited, and could include an anionic, cationic, nonionic or amphoteric surfactant [0283]. Kamimura teaches several anionic surfactants that are known and useful [0286], as well as nonionic surfactants [0319], including, e.g., B-6, polyoxyalkylene lauryl ether, also disclosed by Roh. It would have been obvious to one with ordinary skill in the art before the effective filing date of the claimed invention to include an anionic surfactant in the composition of Roh because Kamimura teaches that they are known, useful alternative surfactants for nonionic surfactants and such are expected to give the predictable result of surfactant properties to the composition. Response to Amendment Applicant’s arguments, see page 4, filed December 26, 2025, with respect to the 35 USC 102 rejections have been fully considered and are persuasive. The rejections of the claims have been withdrawn. The claims are rejected under 35 USC 103 over Walker et al (US 7,365,045 B2) in view of Kamimura (US 2023/0099612 A1), and over Roh et al (KR-20200086180A) in view of Kamimura (US 2023/0099612 A1). Kamimura is relied upon to teach the obviousness of including 1,3-propanediamine in the compositions of Walker and Roh. Response to Arguments Applicant's arguments filed December 26, 2025, have been fully considered but they are not persuasive, to the extent they still apply. Applicant argues that the specification demonstrates a significant and unexpected improvement in silicon etching rates using 1,3-propanediamine. More specifically, applicant points to Examples 3-6 compared to Examples 7-11, and the content of component (B) of 5 to 20% compared to lower amounts in Examples 1 and 2. In response, any showing of unexpected results must be commensurate in scope with the claim language. It is not clear from Tables 1 and 2, that the range of contents for components A, B, and C support the broad ranges cited in the instant claims. Data points are not present both inside and outside of the claimed ranges to show unexpected results within the claimed ranges. For component A, TMAH has two values, 2.38% and zero, which fails to show unexpected results for the other values of TMAH content. Component B in Table 1 shows 1,3-propanediamine in examples 1-6 and 12-14, and comparative example 2. However, the polysilicon etch rate for examples 1-2 (1-2% 1,3-propanediamine) are lower than at 5-20%, but not unexpectedly low. There are also no data points for above 20% to determine whether the rates are unexpected at 20% compared to higher percentages. Example 8 has a lower etch rate for 2% 1,2-propane diamine compared to 1,3-propanediamine, which further suggests that the etch rate for 2% is not unexpected. Examples 12-14 also fail to show sufficient unexpected results for the range of components A-C when a surfactant is also present. Data is only present for 2.38% TMAH, 10% 1,3-propanediamine, and 0.1-0.5% surfactant, not for the claimed ranges of 5-20% 1,3-propane diamine, 77.62% or more of component (C), any content of component (D), and no limitation on the content of component (A). Accordingly, the specification fails to show unexpected results commensurate in scope with the claimed invention. Conclusion Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a). A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action. Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANITA K ALANKO whose telephone number is (571)270-0297. The examiner can normally be reached Monday-Friday, 9 am-5pm. 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 on 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. /ANITA K ALANKO/Primary Examiner, Art Unit 1713
Read full office action

Prosecution Timeline

Mar 28, 2023
Application Filed
Dec 14, 2024
Non-Final Rejection — §103
Mar 14, 2025
Response Filed
May 17, 2025
Final Rejection — §103
Aug 15, 2025
Request for Continued Examination
Aug 28, 2025
Response after Non-Final Action
Sep 25, 2025
Non-Final Rejection — §103
Dec 26, 2025
Response Filed
Mar 09, 2026
Final Rejection — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12577178
SLIDING MEMBER AND METHOD OF MANUFACTURING SLIDING MEMBER
2y 5m to grant Granted Mar 17, 2026
Patent 12577465
METHOD FOR PRODUCING SEMICONDUCTOR TREATMENT LIQUID AND METHOD FOR PRODUCING SEMICONDUCTOR ELEMENT
2y 5m to grant Granted Mar 17, 2026
Patent 12552962
CMP SLURRY COMPOSITION FOR POLISHING TUNGSTEN PATTERN WAFER AND METHOD OF POLISHING TUNGSTEN PATTERN WAFER USING THE SAME
2y 5m to grant Granted Feb 17, 2026
Patent 12545839
SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS
2y 5m to grant Granted Feb 10, 2026
Patent 12534640
POLISHING LIQUID AND POLISHING METHOD
2y 5m to grant Granted Jan 27, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

5-6
Expected OA Rounds
69%
Grant Probability
52%
With Interview (-17.2%)
3y 1m
Median Time to Grant
High
PTA Risk
Based on 677 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month