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 .
Claims Status
Claims 1,4, 6, 8, 10 are rejected. Claim 11 is withdrawn.
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 1,4,6,8 and 10 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 1 recites the limitation "the selective etching" in the eight line of the claim language. There is insufficient antecedent basis for this limitation in the claim. For the purpose of expediting examination and compact prosecution, examiner shall interpret “the selective etching” to be “selectively etching”.
Claims 4, 6, 8, and 10 are rejected for dependence upon a 112(b) rejected instance 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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1, 6, 8, 10 are rejected under 35 U.S.C. 103 as being unpatentable over Brown (U.S. 2012/0247505) and Heo et al (U.S. 2003/0203632).
Regarding claim 1. Brown et al discloses an etching method (Abstract; claims 16-25) comprising: selectively etching a silicon nitride layer against a silicon oxide layer (Abstract), under pressurization conditions ([0040], i.e. Pressure for the steam water vapor mixture can be in the range from 0.2 to 2.0 MPa), using an etching composition ([0043], i.e. a treatment liquid) including a phosphoric acid based on a total weight of the etching composition ([0040], i.e. composition of 85% phosphoric acid by weight),
wherein the etching composition does not include a compound containing a silicon atom ([0030], i.e. The chemical reactions for etching silicon nitride: Si3N4+4H3PO4+12H2O → 3Si(OH)4+4NH4H2PO4 ; [0040]; claims 16-25; examiner makes note that 4H3PO4+12H2O does not include a compound containing a silicon atom).
wherein the etching composition ([0043], i.e. a treatment liquid) is maintained in a liquid phase ([0043], i.e. a treatment liquid) under the pressurization conditions are 2 to 20 atm ([0040], i.e. mixture can be in the range from 0.2 to 2.0 MPa) during the selective etching ([0027], i.e. aqueous phosphoric acid is utilized to illustrate a treatment liquid in the present invention),
wherein the etching method is performed at a temperature of 150C to 300C ([0043, i.e. The inventors found that the treatment liquid can be advantageous at a range of 160 to 200 degrees C. and preferably about 180 degrees C. for a treatment liquid using aqueous phosphoric acid), and
wherein the following (A) to (C) are satisfied:
(A) an etching rate of the silicon nitride layer is 50 A/min or more ([0036], i.e. Silicon nitride etch processes are slow (30-60 Angstrom/min, or A/min) in hot phosphoric acid at 16.degree. C. If the etch rate of silicon nitride can be increased to over 180 A/min),
(B) an etching rate of the silicon oxide layer is 0 to 10 A/min ([0036]; claims 16-18; examiner makes note ((etch rate silicon nitride)/(etch rate of silicon oxide)=(selectivity of silicon nitride to silicon oxide) that etch rate of silicon nitride is 30- over 180 Angstrom/min and with a selectivity of silicon nitride to silicon oxide of 10:1 to 1000:1 would give an silicon oxide rate of 0.18-3 A/min), and
(C) an etching selectivity of the silicon nitride layer to the silicon oxide layer is 2 to 400 (claims 16-18; i.e. etch selectivity ratio is in the range from 10:1 to 1000:1).
Brown et al fails to explicitly disclose wherein the etching composition includes 30 to 70 wt% of the phosphoric acid.
However, Heo et al teaches wherein the etching composition includes 30 to 70 wt% of the phosphoric acid ([Abstract]; water solution containing phosphoric acid (H3PO4) of a concentration of 50-70% by weight).
Since Brown et al and Heo et al discloses etching composition of 85% for silicon nitride, it would have been obvious to one having ordinary skill in the art of semiconductors before the effective filing date of the claimed invention to have combined the etching method as disclosed to modify Brown et al with the teachings of wherein the etching composition includes 30 to 70 wt% of the phosphoric acid as disclosed by Heo et al. The use of water solution containing phosphoric acid of a concentration of 50-70% by weight in Heo et al provides for the etch rate of the nitride film is increased, and the selectivity between the nitride film and an oxide film is kept very high (Heo et al, [Abstract]).
Regarding claim 6. Brown et al and Heo et al discloses all the limitation of the etching method of claim 1 above.
Brown et la further discloses wherein the etching composition has an etching selectivity of 10 to 400 (claims 16-18; i.e. etch selectivity ratio is in the range from 10:1 to 1000:1)
Regarding claim 8. Brown et al and Heo et al discloses all the limitations of the etching method of claim 1 above.
Brown et al further discloses wherein an object to be etched of the etching composition is a wafer (Claim 16) in which both silicon nitride layer (Claim 16) and silicon oxide layer (Claim 16) are exposed to a surface (Claim 16) or a wafer having a stack structure having the silicon nitride layer and the silicon oxide layer as a unit layer.
Regarding claim 10. Brown et al and Heo et al discloses all the limitations of the etching method of claim 1 above.
Brown et al further discloses a method of manufacturing a semiconductor device ([0027]) using the etching method of claim 1 (claims 14-16).
Claims 4 are rejected under 35 U.S.C. 103 as being unpatentable over Brown et al (U.S. 2012/0247505) and Heo et al (U.S. 2003/0203632) as applied to claim 1 above, and further in view of Kim et al (U.S. 2022/0089951).
Regarding claim 4. Brown et al and Heo et al discloses all the limitations of the etching method of claim 1 above.
Brown et al fails to explicitly disclose wherein the following (D) is satisfied: (D) in a vertical stack structure having the silicon oxide layer and the silicon nitride layer as a unit layer, an outer thickness (To) to an inner thickness (Ti) of the silicon oxide layer satisfies the following Equation 1: [Equation 1]
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However, Kim et al teachers wherein the following (D) is satisfied: (D) in a vertical stack structure having the silicon oxide layer and the silicon nitride layer as a unit layer ([0046]), an outer thickness (To) to an inner thickness (Ti) of the silicon oxide layer satisfies the following Equation 1:
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([Abstract], i.e. not only no precipitate occurs but also anomalous growth in which the thickness of the silicon oxide film is rather increased does not occur)
Since Brown et al, Heo et al and Kim et al teach etching silicon nitride, it would have been obvious to one having ordinary skill in the art of semiconductors before the effective filing date of the claimed invention to have combined the etching method as disclosed to modify Brown et al and Heo et al with the teachings of an outer thickness (To) to an inner thickness (Ti) of the silicon oxide layer satisfies the following Equation 1: [Equation 1]
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as disclosed by Kim et al. The use of not only no precipitate occurs but also anomalous growth in which the thickness of the silicon oxide film is rather increased does not occur in Kim et al provides for minimizing defects and reliability reduction (Kim et al, [Abstract]).
“[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” See MPEP 2144.05 II. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382; In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969). For more recent cases applying this principle, see Merck & Co. Inc. v. Biocraft Lab. Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989); In re Kulling, 897 F.2d 1147, 14 USPQ2d 1056 (Fed. Cir. 1990); and In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997); Smith v. Nichols, 88 U.S. 112, 118-19 (1874); In re Williams, 36 F.2d 436, 438 (CCPA 1929). See also KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007). See MPEP 2144.05 II.
Response to Arguments
Applicant's arguments filed May 6, 2026 have been fully considered but they are not persuasive.
On page 5 of applicant’s remarks, applicant appears to argue that Brown does not disclose use of a low-concentration phosphoric acid solution of 30 to 70 wt%, nor does it disclose the reaction conditions of high temperature and high pressure.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., the reaction conditions of high temperature and high pressure) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Examiner respectfully points out that Brown et al was not used disclose phosphoric acid solution of 30 to 70 wt%, and that Heo et al teaches phosphoric acid solution of 30 to 70 wt% as pointed out above.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
On page 8 of applicant’s remarks, applicant appears to argue that Brown et al does not disclose 30-70 wt% of phosphoric acid.
Examiner respectfully points out that Brown et al was not used disclose phosphoric acid solution of 30 to 70 wt%, and that Heo et al teaches phosphoric acid solution of 30 to 70 wt%. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
On page 8 of applicant’s remarks, applicant appears to argue that Heo et al requires chemical additives such as hydrofluoric acid (HF), to ensure an etching rate while using a low-concentration phosphoric acid of 50 to 70 wt%.
Examiner respectfully points out that applicant’s claim states etching composition including 30 to 70 wt% of a phosphoric acid based. The term “including” is a transitional phrase. The transitional term "comprising", which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. See, e.g., Mars Inc. v. H.J. Heinz Co., 377 F.3d 1369, 1376, 71 USPQ2d 1837, 1843 (Fed. Cir. 2004) ("[L]ike the term ‘comprising,’ the terms ‘containing’ and ‘mixture’ are open-ended."). Invitrogen Corp. v. Biocrest Manufacturing, L.P., 327 F.3d 1364, 1368, 66 USPQ2d 1631, 1634 (Fed. Cir. 2003) ("The transition ‘comprising’ in a method claim indicates that the claim is open-ended and allows for additional steps."); Genentech, Inc. v. Chiron Corp., 112 F.3d 495, 501, 42 USPQ2d 1608, 1613 (Fed. Cir. 1997) ("Comprising" is a term of art used in claim language which means that the named elements are essential, but other elements may be added and still form a construct within the scope of the claim.); Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261, 229 USPQ 805 (Fed. Cir. 1986); In re Baxter, 656 F.2d 679, 686, 210 USPQ 795, 803 (CCPA 1981); Ex parte Davis, 80 USPQ 448, 450 (Bd. App. 1948) ("comprising" leaves "the claim open for the inclusion of unspecified ingredients even in major amounts"). See MPEP 2111.03 (I).Applicant appears to further argue that Brown does not disclose suppress the boiling point by pressurizing the entire reactor.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., suppress the boiling point by pressurizing the entire reactor) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Examiner respectfully points out that Brown discloses same pressurization range and temperature range as applicant’s claimed method step.
Applicant appears to further argue that Heo et al does not disclose the required temperature claimed nor pressuring the entire reactor to 2 to 20atm
Examiner respectfully points out that Heo et al was not used to disclose the claimed temperature range and claimed pressure range, Brown et al discloses applicant’s claimed temperature range and pressure range.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
On page 10 of applicant’s remarks, applicant appears to argue that neither Brown et al nor Heo provide any teachings regarding the achievement of high etching efficiency by preventing the boiling of a low-concentration phosphoric acid solution through high-temperature and pressurized process conditions.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., the achievement of high etching efficiency by preventing the boiling of a low-concentration phosphoric acid solution through high-temperature and pressurized process conditions) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Furthermore, Examiner respectfully points out that Brown et al and Heo et al discloses all the limitations of applicant’s amended claim 1.
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 SCOTT E BAUMAN whose telephone number is (469)295-9045. The examiner can normally be reached M-F, 9-5 CST.
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/S.E.B./ Examiner, Art Unit 2815 /JOSHUA BENITEZ ROSARIO/Supervisory Patent Examiner, Art Unit 2815
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