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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 4/28/26 and 4/1/26 has been entered.
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 1-2, 4-14, 16-17, 20, and 24 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.
Claims 1-2, 8-10, 17, 20, and 24 recite the term “about.” The term "about" is a relative term which renders the claims indefinite; it is not defined by the claim(s), 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. “About” is defined as "almost or nearly—used to indicate that a number, amount, time, etc., is not exact or certain” (see Merriam Webster online dictionary). This language is indefinite as the specification does not describe how “almost or nearly” a value must be to be within “about” a specific target. The term “about” modifies a target, and implicitly requires boundaries at some maximum value above the target and at some minimum value below the target beyond which one is not “about” the target any more. Neither the claims, nor the specification, defines these boundaries. Thus, it is unclear whether one must be within some small percentage of deviation of the target (such as 0.01 %, 0.1 %, 1 %, 2 %, 5 %, 10 %, or some other percentage) or within a certain number of units of the target and specifically which of these possible values defines the boundaries. If one were to poll 100 people having ordinary skill in the art, there would be many different responses for the boundaries. Thus, determining whether one is infringing the limitation is subjective, rather than objective, and thus the claims are unclear. Therefore, the claims are rejected as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant, regards as the invention. For the purposes of examination, the examiner interprets “about” as within 25%. However, appropriate correction and/or clarification is requested.
Claims 2, 4-14, and 16 inherit the 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, rejections based on their dependencies on claim 1. Claim 20 inherits the 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, rejections based on its dependencies on claim 17.
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) 1-2, 6-9, and 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chaudhuri et al. (U.S. 2021/0249513 A1; “Chaudhuri”) in view of Hirasaki (U.S. 2022/0328321 A1).
Regarding claim 1, Chaudhuri discloses a semiconductor device, comprising:
A substrate (substrate, Fig. 5B), the substrate comprising silicon, silicon carbide, or sapphire ([0038]);
A semiconductor structure (AlN Buffer, UID GaN, Mg:GaN, Fig. 5B) on the substate, the semiconductor structure comprising:
An aluminum nitride layer (AlN buffer, Fig. 5B) on the substrate, the aluminum nitride layer having a thickness of 180 nm or greater (Fig. 5B; [0059]);
A Group III-nitride semiconductor structure (UID GaN and Mg:GaN, Fig. 5B) on the aluminum nitride layer, the thickness of the aluminum nitride layer being at least 1.5 times greater than a second thickness of the Group III-nitride layer semiconductor structure, wherein the Group III-nitride semiconductor structure is at least about 275 angstroms from a [bottom] surface of the semiconductor structure ([0058]-[0059]).
Yet, Chaudhuri does not disclose the aluminum nitride layer is an epitaxial layer. However, Hirasaki discloses forming an aluminum nitride layer on a substrate by an epitaxial process, thereby yielding an epitaxial layer ([0057]). Because both Chaudhuri and Hirasaki teach methods of forming aluminum nitride layers on substrates comprising silicon, silicon carbide, or sapphire, it would have been obvious to one skilled in the art at the time the invention was effectively filed to substitute one method for the other to achieve the predictable result of the aluminum nitride being an epitaxial layer. KSR International Co. v. Teleflex Inc., 82 USPQ2d 1385 (2007).
Regarding claim 2, Chaudhuri and Hirasaki disclose the thickness of the aluminum nitride layer is in a range between about 500 nm and about 1000 nm (Chaudhuri: Fig. 5B discloses a thickness of 400 nm which is considered “about 500 nm” since “about” is interpreted by the examiner as within 25% (see 35 USC 112 rejection above)). Chaudhuri and Hirasaki disclose the aluminum nitride layer is an epitaxial layer (see claim 1 rejection above).
Regarding claim 6, Chaudhuri and Hirasaki disclose the aluminum nitride layer and the Group III-nitride semiconductor structure are metal polar (Chaudhuri: [0045]-[0048]). Chaudhuri and Hirasaki disclose the aluminum nitride layer is an epitaxial layer (see claim 1 rejection above).
Regarding claim 7, Chaudhuri and Hirasaki disclose the Group III-nitride semiconductor structure (Chauhuri: UID GaN and Mg:GaN, Fig. 5B) comprises a buffer layer (Chauhuri: UID GaN, Fig. 5B), wherein the buffer layer comprises AlwGa1-wN, where w is 0<w<0.1 (w=0).
Regarding claim 8, Chaudhuri and Hirasaki disclose a thickness of the buffer layer (Chauhuri: UID GaN, Fig. 5B) is about 700 nm or less.
Regarding claim 9, Chaudhuri and Hirasaki disclose a thickness of the buffer layer (Chauhuri: UID GaN, Fig. 5B) is about 200 nm or less.
Regarding claim 17, Chaudhuri discloses a semiconductor device, comprising:
A substrate (substrate, Fig. 5B), the substrate comprising silicon, silicon carbide, or sapphire ([0038]);
A semiconductor structure on the substrate, the semiconductor structure comprising:
An aluminum nitride layer (AlN buffer, Fig. 5B) on the substrate, the aluminum nitride layer having a first thickness (Fig. 5B; [0059]);
A gallium nitride layer (UID GaN and Mg:GaN, Fig. 5B) on the aluminum nitride layer having a second thickness ([0058]-[0059]);
Wherein the first thickness is at least 1.5 times greater than the second thickness (Fig. 5B), wherein the gallium nitride layer (UID and Mg: GaN, Fig. 5B) is at least about 275 angstroms from a [bottom] surface of the semiconductor structure ([0058]-[0059]).
Yet, Chaudhuri does not disclose the aluminum nitride layer is an epitaxial layer. However, Hirasaki discloses forming an aluminum nitride layer on a substrate by an epitaxial process, thereby yielding an epitaxial layer ([0057]). Because both Chaudhuri and Hirasaki teach methods of forming aluminum nitride layers on substrates comprising silicon, silicon carbide, or sapphire, it would have been obvious to one skilled in the art at the time the invention was effectively filed to substitute one method for the other to achieve the predictable result of the aluminum nitride being an epitaxial layer. KSR International Co. v. Teleflex Inc., 82 USPQ2d 1385 (2007).
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chaudhuri et al. (U.S. 2021/0249513 A1; “Chaudhuri”) in view of Hirasaki (U.S. 2022/0328321 A1) as applied to claim 1 above, as evidenced by teaching reference Dagli (“Thermal conductivity of AlN, GaN, and AlxGa1-x alloys as a function of composition, temperature, crystallographic direction, and isotope disorder from first principles”, 2019).
Regarding claim 4, Chaudhuri and Hirasaki disclose the Group III-nitride semiconductor structure comprises GaN (Chaudhuri: UID GaN and Mg:GaN, Fig. 5B). Teaching reference Dagli indicates that the thermal conductivity of aluminum nitride is greater than that of GaN (Abstract).
Claim(s) 13-14 and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chaudhuri et al. (U.S. 2021/0249513 A1; “Chaudhuri”) as modified by Hirasaki (U.S. 2022/0328321 A1) as applied to claim 1 above, and further in view of Stoffels et al. (U.S. 2017/0263700 A1; “Stoffels”).
Regarding claim 13, Chaudhuri and Hirasaki disclose a Group III-nitride semiconductor structure (Chaudhuri: UID GaN and Mg:GaN, Fig. 5B) but do not disclose one or more cap layers on the Group III-nitride semiconductor structure. However, Stoffels discloses a cap layer (9, Fig. 4) on (“on top of”) a Group III-nitride semiconductor structure (2, 10, 3, Fig. 4) ([0044]). This has the advantage of protecting the Group III-nitride semiconductor structure. Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was effectively filed to modify the invention of Chaudhuri and Hirasaki with a cap layer on the Group III-nitride semiconductor structure, as taught by Stoffels, so as to protect the Group III-nitride semiconductor structure.
Regarding claim 14, Chaudhuri and Hirasaki disclose a Group III-nitride semiconductor structure (Chaudhuri: UID GaN and Mg:GaN, Fig. 5B) but do not disclose a source contact, drain contact, and gate contact on the Group III-nitride semiconductor structure. However, Stoffels discloses a source contact (6, Fig. 4), drain contact (7, Fig. 4), and gate contact (8, Fig. 4) on a Group III-nitride semiconductor structure (2, 10, 3, Fig. 4) ([0044]). This has the advantage of forming a high electron mobility transistor (HEMT) device. Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was effectively filed to modify the invention of Chaudhuri and Hirasaki with a source contact, drain contact, and gate contact on the Group III-nitride semiconductor structure, as taught by Stoffels, so as to form a HEMT device.
Regarding claim 16, Chaudhuri and Hirasaki disclose a Group III-nitride semiconductor structure (Chaudhuri: UID GaN and Mg:GaN, Fig. 5B; [0044]) within a semiconductor device (Chaudhuri: [0002]-[0003]) but do not disclose the device is a high electron mobility transistor (HEMT) device. However, Stoffels discloses incorporating a Group III-nitride semiconductor structure within a HEMT device ([0043]-[0044], [0002]). HEMT devices have the advantage of higher breakdown strengths and lower specific on-state resistances as compared to other transistor devices. Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was effectively filed to modify the invention of Chaudhuri and Hirasaki with the semiconductor device being a HEMT device, as taught by Stoffels, so as to form a reliable and high-performing semiconductor device.
Allowable Subject Matter
Claims 5, 10-12, and 20 would be allowable if rewritten 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 and to include all of the limitations of the base claim and any intervening claims.
Claim 24 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.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-2, 4-14, 16-17, 20, and 24 are moot in view of the new grounds of rejection.
Conclusion
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/REEMA PATEL/Primary Examiner, Art Unit 2812 5/7/2026
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