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 without traverse of Group I (claims 1-12) in the reply filed on 12/10/2025 is acknowledged.
Claims 13-14 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group II, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 12/10/2025.
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 1-12 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.
The term “a high concentration of C” in claims 1 and 10 is a relative term which renders the claim indefinite. The term “a high concentration of C” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, claim 1 recites the broad recitation "high concentration of C", and the claim also recites “a concentration of the C in the mixed crystal layer is at least 1.0 x 10 +21 cm-3” which is the narrower statement of the range/limitation. The claim(s) are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims.
Claims 2-9, 11, and 12 are indefinite due to their dependance on indefinite claims.
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.
Claim(s) 1-4, and 6-8 are rejected under 35 U.S.C. 103 as being unpatentable over Khalil (US 2022/0208975).
Regarding claim 1, Khalil discloses a nitride semiconductor epitaxial substrate comprising: a Si substrate (Fig.5, numeral 102; [0019]); a nitride semiconductor epitaxial layer (108) disposed above the Si substrate (102); and a mixed crystal layer (104); disposed between the Si substrate (102) and the nitride semiconductor epitaxial layer (108), the mixed crystal layer containing Si and a group III metal element ([0019]), the mixed crystal layer containing a high concentration of C ([0020]; [0021]), and the mixed crystal layer contains a transition metal element at a concentration of at most 5.0 x 10+16cm-3 ([0021]).
Khalil does not disclose wherein a concentration of the C in the mixed crystal layer is at least 1.0 x 10+21cm-3.
Khalil however discloses that the dopant concentration of layers the mixed crystal layer can be varied to optimize the resistivity of the layers ([0020]).
It would have been therefore obvious to one of ordinary skill in the art at the time the invention was filed to adjust the concentration of C to be in the claimed range for the purpose of optimizing the resistivity of the mixed crystal layer (Khalil, [0020]).
Regarding claim 2, Khalil discloses wherein the transition metal element is at least one of Fe, Cr, Cu, Ni, Mn, or Co ([0020]).
Regarding claim 3, Khalil discloses wherein the transition metal element is at least one of Fe, Cr, Cu, Ni, Mn, or Co, and a concentration of each of a plurality of transition metal elements in the mixed crystal layer is at most 5.0 x 10+16cm-3, the plurality of transition metal elements each being the transition metal element ([0020]).
Regarding claim 4, Khalil discloses wherein the group III metal element is identical to a group III metal element contained in the nitride semiconductor epitaxial layer ([0020]; [0021]).
Regarding claim 6, Khalil discloses wherein the mixed crystal layer has a thickness of at most 50 nm ([0020]).
Regarding claim 7, Khalil does not disclose wherein the concentration of the C in the mixed crystal layer is at most 1.0 x 10+22cm3.
Khalil however discloses that the dopant concentration of layers the mixed crystal layer can be varied to optimize the resistivity of the layers ([0020]).
It would have been therefore obvious to one of ordinary skill in the art at the time the invention was filed to adjust the concentration of C to be in the claimed range for the purpose of optimizing the resistivity of the mixed crystal layer (Khalil, [0020]).
Regarding claim 8, Khalil discloses wherein the nitride semiconductor epitaxial layer (108) includes an AlN layer on a mixed crystal layer side ([0022]).
Claim(s) 5 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Khalil as applied to claim 1 above, and further in view of Sato (US 2019/0214492).
Regarding claim 5, Khalil does not disclose wherein the mixed crystal layer has a C concentration distribution in which the concentration of the C is higher on a nitride semiconductor epitaxial layer side and is lower on a Si substrate side, the concentration of the C gradually decreasing from the nitride semiconductor epitaxial layer side toward the Si substrate side.
Sato however discloses wherein the mixed crystal layer has a C concentration distribution in which the concentration of the C is higher on a nitride semiconductor epitaxial layer side and is lower on a Si substrate side, the concentration of the C gradually decreasing from the nitride semiconductor epitaxial layer side toward the Si substrate side (Abstract; [0069]; Fig. 7).
It would have been therefore obvious to one of ordinary skill in the art at the time the invention was filed to modify Khalil with Sato to have the mixed crystal layer has a C concentration distribution in which the concentration of the C is higher on a nitride semiconductor epitaxial layer side and is lower on a Si substrate side, the concentration of the C gradually decreasing from the nitride semiconductor epitaxial layer side toward the Si substrate side for the purpose of suppressing leakage current (Sato, Abstract).
Regarding claim 9, Khalil does not disclose wherein the nitride semiconductor epitaxial layer includes a first nitride semiconductor layer and a second nitride semiconductor layer, and the first nitride semiconductor layer contains C at a concentration that is higher than a concentration of C in the second nitride semiconductor layer.
Sato however discloses wherein the nitride semiconductor epitaxial layer includes a first nitride semiconductor layer and a second nitride semiconductor layer, and the first nitride semiconductor layer contains C at a concentration that is higher than a concentration of C in the second nitride semiconductor layer (Abstract; [0067]- [0069]).
It would have been therefore obvious to one of ordinary skill in the art at the time the invention was filed to modify Khalil with Sato to have the nitride semiconductor epitaxial layer includes a first nitride semiconductor layer and a second nitride semiconductor layer, and the first nitride semiconductor layer contains C at a concentration that is higher than a concentration of C in the second nitride semiconductor layer for the purpose of suppressing leakage current (Sato, Abstract).
Allowable Subject Matter
Claims 10-12 would be allowable if rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action.
The following is a statement of reasons for the indication of allowable subject matter:
The search of the prior art does not disclose or reasonably suggest that a concentration of the C in the mixed crystal layer is higher than a concentration of C in each of layers included in the heterostructure epitaxial layer as required by claim 10.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JULIA SLUTSKER whose telephone number is (571)270-3849. The examiner can normally be reached Monday-Friday, 9 am-6 pm.
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/JULIA SLUTSKER/Primary Examiner, Art Unit 2891