Prosecution Insights
Last updated: October 04, 2026
Application No. 18/016,725

ETCHANT COMPOSITION FOR ADJUSTING ETCHING SELECTIVITY OF TITANIUM NITRIDE FILM WITH RESPECT TO TUNGSTEN FILM, AND ETCHING METHOD USING SAME

Final Rejection §103
Filed
Jan 18, 2023
Priority
Aug 04, 2020 — RE 10-2020-0097214 +1 more
Examiner
LAOBAK, ANDREW KEELAN
Art Unit
1713
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Young Chang Chemical Co. Ltd.
OA Round
2 (Final)
75%
Grant Probability
Favorable
3-4
OA Rounds
0m
Est. Remaining
99%
With Interview

Examiner Intelligence

Grants 75% — above average
75%
Career Allowance Rate
46 granted / 61 resolved
+10.4% vs TC avg
Strong +34% interview lift
Without
With
+34.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 2m
Avg Prosecution
27 currently pending
Career history
84
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
62.6%
+22.6% vs TC avg
§102
16.0%
-24.0% vs TC avg
§112
17.3%
-22.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 61 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 . Status of the Claims This is a final office action in response to the applicant’s arguments and remarks filed on 02/22/2026. Claims 1 and 11-13 are pending in the current office action. Claim 1 has been amended by the applicant. Claims 2-10 have been cancelled. Claims 11-13 remain withdrawn. Status of the Rejection The Claim objections have been overcome by the applicant's amendments. All 35 U.S.C. § 112(b) rejections from the previous office action are withdrawn in view of the Applicant’s amendment. The rejection of claims 2-10 is obviated by the Applicant’s cancellation. All 35 U.S.C. § 103 rejections from the previous office action are substantially maintained and modified only in response to the amendments to the claims. 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. Claim 1 is rejected under 35 U.S.C. 103 as being unpatentable over Hong et al. (US-20160257880-A1) Regarding Claim 1, Hong teaches an etchant composition (Paragraph [0010] teaches an etchant composition) comprising: a) an inorganic acid selected from the group consisting of sulfuric acid, phosphoric acid, and a mixture thereof (Paragraph [0014] comprises sulfuric acid, which is an inorganic acid); b) an oxidizing agent selected from the group consisting of hydrogen peroxide, nitric acid, tert-butyl hydroperoxide, and 2-butanone peroxide (Paragraph [0014] comprises a peroxide, which is an oxidizing agent. Paragraph [0026] The peroxide can be hydrogen peroxide and tert-butyl hydroperoxide); c) an additive selected from the group consisting of tetramethylammonium sulfate, ethylenediamineammonium sulfate, ammonium methylsulfate, dodecyltrimethylammonium sulfate, ammonium lauryl sulfate, diethylammonium octylsulfate, ammonium sulphate, 2- hydroxyethylammonium dodecylsulfate and mixtures thereof (Paragraph [0014] comprises an inorganic ammonium salt. Paragraph [0029] inorganic ammonium salt can be ammonium sulfate); and d) water as a balance (Paragraph [0014] composition comprises water), wherein an etching rate of a titanium nitride film is 43 A/min to 94 A/min, and an etching selectivity of the titanium nitride film to a tungsten film is 3.8 to 15 (When the structure recited in the reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent. The Courts have held that it is well settled that where there is a reason to believe that a functional characteristic would be inherent in the prior art, the burden of proof then shifts to the applicant to provide objective evidence to the contrary. See MPEP 2112.01(I). Given that the composition based on the disclosure in Hong is substantially similar to that in instant claim, it is the examiner's position that the composition would inherently have the instantly claimed features of the “etching rate of titanium nitride” and “etching selectivity of the titanium nitride film to a tungsten film”. Since PTO cannot conduct experiments the proof of burden is shifted to the applicants to establish a nonobviousness difference. See MPEP 2112. Further, this limitation could be considered a limitation of intended use that does not further limit the claimed invention. While features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function. See MPEP 2114. Since the structure of the prior art teaches all of the structural limitations of the claim, the structure is considered capable of meeting the intended use limitations. However, for purposes of compact prosecution, examiner notes that Hong teaches in Paragraph [0043] Table 2, in example 12 a composition with a TiN etch rate of 56.0 Å/min and an etching selectivity of TiN to tungsten of 8) Hong fails to teach that the inorganic acid is present in an amount of 81% to 95% by weight, based on the total weight of the etchant composition, the oxidizing agent is present in an amount of 0.1% to 3% by weight, based on the total weight of the etchant composition, the additive being present in an amount of 0.002% to 0.05% by weight, based on the total weight of the etchant composition. However, Hong teaches that sulfuric acid can be included in the composition from 75-95% by weight (Paragraph [0014]), that the peroxide can be included in the composition at 0.3-10% by weight (Paragraph [0014]), and that the ammonium salt can be included in the composition at 0.0001-3% by weight (Paragraph [0014]). It would have been obvious to one of ordinary skill in the art to have selected and incorporated sulfuric acid at a level within the disclosed range of 75-95% by weight, including at amounts that overlap with the claimed range of 81-95% by weight. It would have been obvious to one of ordinary skill in the art to have selected and incorporated the peroxide at a level within the disclosed range of 0.3-10% by weight, including at amounts that overlap with the claimed range of 0.1% to 3% by weight. It would have been obvious to one of ordinary skill in the art to have selected and incorporated the ammonium salt at a level within the disclosed range of 0.0001-3% by weight, including at amounts that overlap with the claimed range of 0.002% to 0.05% by weight. It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. See MPEP 2144.05 (I). Response to Arguments Applicant’s arguments, see Remarks Pg. 1-3, filed 02/22/2026, with respect to the 35 U.S.C. § 103 rejection have been fully considered and are not persuasive. Applicant argues that the cited prior art fails to teach the etching rate and etching selectivity of the claimed composition. Examiner respectfully disagrees. As outlined in the rejection above, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Additionally, as noted above Hong does teach an example with an etching rate and etching selectivity within the claimed ranges. Applicant argues that one of ordinary skill in the art would not have had the motivation or a reasonable expectation of success in achieving the claimed invention based on the cited prior art, due to the differences in the claimed ranges for the composition ingredients and the ranges taught by the prior art. Examiner respectfully disagrees. Examiner notes, as outlined above, that the claimed ranges significantly overlap with the taught ranges and the invention of the cited prior art is taught to be have the intended use of etching titanium nitride while minimizing the etching of tungsten. These teachings provide one of ordinary skill in the art a motivation and reasonable expectation of success to create a composition that achieves those taught uses through selection within the taught ranges. Applicant argues that the allowance of counterpart applications in other jurisdictions provides support for the patentability of the instant application. Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references. Conclusion THIS ACTION IS MADE FINAL. 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 ANDREW KEELAN LAOBAK whose telephone number is (703)756-5447. The examiner can normally be reached Monday - Friday 8:00am - 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. /A.K.L./Examiner, Art Unit 1713 /DUY VU N DEO/Primary Examiner, Art Unit 1713
Read full office action

Prosecution Timeline

Jan 18, 2023
Application Filed
Aug 25, 2025
Non-Final Rejection mailed — §103
Feb 22, 2026
Response Filed
Apr 10, 2026
Final Rejection mailed — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12751228
TRANSDUCERS INCLUDING LASER ETCHED SUBSTRATES
2y 6m to grant Granted Sep 29, 2026
Patent 12740357
ETCHING METHOD AND ETCHING APPARATUS
3y 7m to grant Granted Sep 15, 2026
Patent 12733424
CLEANING LIQUID AND METHOD FOR CLEANING SEMICONDUCTOR SUBSTRATE
3y 9m to grant Granted Sep 08, 2026
Patent 12717235
ALKALINE DEVELOPER SOLUABLE SILICON-CONTAINING RESIST UNDERLAYER FILM-FORMING COMPOSITION
4y 6m to grant Granted Aug 25, 2026
Patent 12713856
PLASMA PROCESSING METHOD AND PLASMA PROCESSING SYSTEM
3y 6m to grant Granted Aug 18, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

3-4
Expected OA Rounds
75%
Grant Probability
99%
With Interview (+34.5%)
3y 2m (~0m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 61 resolved cases by this examiner. Grant probability derived from career allowance 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