DETAILED ACTION
General Remarks
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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 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.
When responding to this office action, applicants are advised to provide the examiner with line numbers and page numbers in the application and/or references cited to assist the examiner in locating appropriate paragraphs.
Per MPEP 2111 and 2111.01, the claims are given their broadest reasonable interpretation and the words of the claims are given their plain meaning consistent with the specification without importing claim limitations from the specification.
Status of claim(s) to be treated in this office action:
Independent: 1 and 14.
Pending: 1-16.
Response to Amendment
The Amendment filed on 11/19/2025 has been entered.
Response to Arguments
Applicant’s arguments "Applicant Arguments/Remarks Made in an Amendment" with the "Amendment/Req. Reconsideration-After Non-Final Reject" filed on 11/19/2025, have been fully considered, the Applicant’s arguments describe that in the Kinoshita’s (US 20190189834 A1), "…Kinoshita only discloses a buffer layer on top of the substrate and that buffer is not a nucleation layer" and Kinoshita does not discloses “wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of the epitaxial layer”. However, the Applicant’s arguments are not persuasive because the Kinoshita’s describes that the buffer layer 12 also work as a nucleation layer, “increasing a yield of a crystal growth process” ([0031], Fig. 1), and the bag gap difference is disclosed in [0071], see the rejection below.
Claim Objections
Claim 2 is objected to because of the following informalities: “the lower layer each comprise at least one of GaN, AlN, InN,”. It should be read “the lower layer each comprise at least one of GaN, AlN, InN.
Appropriate correction is required.
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.
Claim 1-16 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.
Regarding claim 1, it recites the limitation “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of the epitaxial layer; and an epitaxial layer, formed on the buffer layer…” is not explained. The limitation has an antecedent issue of “the epitaxial layer; and an epitaxial layer”. Therefore, it is indefinite. For the examination purpose and according to the disclosure, the limitation “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of the epitaxial layer; and an epitaxial layer, formed on the buffer layer” is interpreted as “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of an epitaxial layer and the epitaxial layer, formed on the buffer layer…”.
Regarding claims 2-13, those are rejected under 35 U.S.C. 112 (b), because of their dependency status from claim 1.
Regarding claim 14, it recites the limitation “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of the epitaxial layer; and an epitaxial layer, formed on the buffer layer…” is not explained. The limitation has an antecedent issue of “the epitaxial layer; and an epitaxial layer”. Therefore, it is indefinite. For the examination purpose and according to the disclosure, the limitation “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of the epitaxial layer; and an epitaxial layer, formed on the buffer layer” is interpreted as “…wherein the band gap differences of the K double-layer structures gradually decrease from one side of the nucleation layer to one side of an epitaxial layer and the epitaxial layer, formed on the buffer layer…”.
Regarding claims 15-16, those are rejected under 35 U.S.C. 112 (b), because of their dependency status from claim 14.
Claim Rejections - 35 USC § 103
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.
Notes: when present, semicolon separated fields within the parenthesis (; ;) represent, for example, as (30A; Fig 2B; [0128]) = (element 30A; Figure No. 2B; Paragraph No. [0128]). For brevity, the texts “Element”, “Figure No.” and “Paragraph No.” shall be excluded, though; additional clarification notes may be added within each field. The number of fields may be fewer or more than three indicated above. These conventions are used throughout this document.
Claims 1-2, 4 and 9-16 are rejected under 35 U.S.C. 103 as being unpatentable over Kinoshita (US 20190189834 A1, hereinafter Kinoshita, of the record), in view of Huang et al. (US 20210017669 A1, hereinafter Huang, of the record).
Re: Independent Claim 1, Kinoshita discloses a nitride epitaxial structure, comprising:
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Kinoshita’s Figure 1-Annotated.
a substrate (11 a substrate made of AlN in [0022], Fig. 1);
a nucleation layer (12 a buffer layer that works as a nucleation layer, layer 12 increasing a yield of a crystal growth process in [0022, 0031], Fig. 1), formed on the substrate (11), wherein the nucleation layer (12) is an aluminum nitride layer or a gallium nitride layer (12 made of AlN in [0031], Fig. 1);
a buffer layer (13A a first layer having a superlattice that works as a buffer layer preventing a sharp variation in the lattice constant in [0048,0071], Fig. 1), formed on the nucleation layer (12), wherein the buffer layer (13A) comprises K stacked group-III nitride double-layer structures (13A including pairs of a well layer and a barrier layer, which are made of AlGaN, are laminated for a plurality of times [0071]), K ≥ 3, each double-layer structure (a pair of 13A) comprises an upper layer and a lower layer that are stacked (an upper barrier layer and lower well layer in [0071]), a band gap of a material of the upper layer is greater than a band gap of a material of the lower layer (the upper layer corresponding to the barrier layer having a greater bandgap of the lower layer corresponding to the well layer in [0071]), a band gap difference (BB-BW a bandgap difference between barrier layer and well layer in [0071]) of each double-layer structure is a difference between the band gap of the material of the upper layer (barrier layer) and the band gap of the material of the lower layer (well layer), and band gap differences (BB1-BW1, BB2-BW2, BB3-BW3) of the K double-layer structures generally present a gradient trend along a thickness direction of the buffer layer (the well layer having an Al composition reduced, stepwise toward the active layer 14 [0071]); wherein the band gap differences (BB1-BW1, BB2-BW2, BB3-BW3) of the K double-layer structures gradually decrease (the well layer having an Al composition reduced, stepwise toward the active layer 14 in [0071]) from one side of the nucleation layer (12) to one side of a layer (14 an active layer in [0023], Fig. 1); and
the layer (14), formed on the buffer layer (13A), wherein a material of the layer (14) comprises group-III nitride (14 composed of an AlGaN layer in [0038]).
Kinoshita does not expressly disclose an epitaxial layer (14 Fig. 1), formed on the buffer layer.
However, in the same semiconductor device field of endeavor, Huang discloses an epitaxial layer (106 a nitride semiconductor layer formed by molecular beam epitaxy (MBE) in [0029], Fig. 1), formed on the buffer layer (104 a buffer layer in [0029], Fig. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Huang’s feature of an epitaxial layer, formed on the buffer layer to Kinoshita’s device to improve the epitaxial quality and facilitate the subsequent device development. ([0027], Huang).
Regarding Claim 2, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein the material of the upper layer (barrier layer Kinoshita) and the material of the lower layer (well layer Kinoshita) each comprise at least one of GaN, AlN, InN (pairs of a well layer and a barrier layer, which are made of AlGaN, are laminated for a plurality of times [0071] Kinoshita).
Regarding Claim 4, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein the band gap differences (BB1-BW1, BB2-BW2, BB3-BW3 Kinoshita) of the K double-layer structures gradually decrease (the well layer having an Al composition reduced, stepwise toward the active layer 14 [0071] Kinoshita) from one side of the nucleation layer (12, Kinoshita) to one side of the epitaxial layer (14’Kinoshita after applied Huang).
Regarding Claim 9, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein a thickness of each double-layer structure (a pair of 13A Kinoshita) is less than 100 nm (the thickness of 13A is 200 nm, having a plurality of pairs of layers such as 3 pairs, then each pair of 13A has a thickness less than 100nm).
Regarding Claim 10, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein a material of the epitaxial layer (14’Kinoshita after applied Huang) comprises one or more of GaN, AlN, InN, AlGaN, InGaN, InAlN and InAlGaN (14 composed of an AlGaN layer in [0038], Kinoshita).
Regarding Claim 11, Kinoshita modified by Huang discloses the nitride epitaxial structure (14’Kinoshita after applied Huang) according to claim 1, wherein a thickness of the epitaxial layer (14’Kinoshita after applied Huang) is greater than or equal to 300 nm (14 including 3 well layers and 4 barrier layers, wherein the thickness of the well layer is 3nm and the thickness of the barrier layer is 7nm in [0060, 0068], Kinoshita).
Regarding Claim 12, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein the substrate (11 Fig. 1, Kinoshita) comprises a silicon substrate, a sapphire substrate, a silicon-on-insulator substrate, a gallium nitride substrate, a gallium arsenide substrate, an indium phosphide substrate, an aluminum nitride substrate, a silicon carbide substrate, a quartz substrate, or a diamond substrate (11 made of AlN in [0022], Fig. 1, Kinoshita).
Regarding Claim 13, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1, wherein a thickness of the nucleation layer (12) is 10 nm to 300 nm (12 having a thickness of 30 to 100 nm in [0031], Fig. 1, Kinoshita).
Re: Independent Claim 14, Kinoshita discloses a semiconductor device, comprising:
at least one input and one output (16,17 n-electrode16 and p-electrode 17 in [0041], Fig. 1); and
a nitride epitaxial structure (10 a light-emitting element in [0041]) that further includes:
a substrate (11 a substrate made of AlN in [0022], Fig. 1);
a nucleation layer (12 a buffer layer in [0022], Fig. 1), formed on the substrate (11), wherein the nucleation layer (12) is an aluminum nitride layer or a gallium nitride layer (12 made of AlN in [0031], Fig. 1);
a buffer layer (13A a first layer having a superlattice that works as a buffer layer preventing a sharp variation in the lattice constant in [0048,0071], Fig. 1), formed on the nucleation layer (12), wherein the buffer layer (13A) comprises K stacked group-III nitride double-layer structures (13A including pairs of a well layer and a barrier layer, which are made of AlGaN, are laminated for a plurality of times [0071]), K ≥ 3, each double-layer structure (a pair of 13A) comprises an upper layer and a lower layer that are stacked (an upper barrier layer and lower well layer in [0071]), a band gap of a material of the upper layer is greater than a band gap of a material of the lower layer (the upper layer corresponding to the barrier layer having a greater bandgap of the lower layer corresponding to the well layer in [0071]), a band gap difference (BB-BW a bandgap difference between barrier layer and well layer in [0071]) of each double-layer structure is a difference between the band gap of the material of the upper layer (barrier layer) and the band gap of the material of the lower layer (well layer), and band gap differences (BB1-BW1, BB2-BW2, BB3-BW3) of the K double-layer structures generally present a gradient trend along a thickness direction of the buffer layer (the well layer having an Al composition reduced, stepwise toward the active layer 14 [0071]) wherein the band gap differences (BB1-BW1, BB2-BW2, BB3-BW3) of the K double-layer structures gradually decrease (the well layer having an Al composition reduced, stepwise toward the active layer 14 in [0071]) from one side of the nucleation layer (12) to one side of a layer (14 an active layer in [0023], Fig. 1); and
the layer (14), formed on the buffer layer (13A), wherein a material of the layer (14) comprises group-III nitride (14 composed of an AlGaN layer in [0038]).
Kinoshita does not expressly disclose an epitaxial layer (14 Fig. 1), formed on the buffer layer.
However, in the same semiconductor device field of endeavor, Huang discloses an epitaxial layer (106 a nitride semiconductor layer formed by molecular beam epitaxy (MBE) in [0029], Fig. 1), formed on the buffer layer (104 a buffer layer in [0029], Fig. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Huang’s feature of an epitaxial layer, formed on the buffer layer to Kinoshita’s device to improve the epitaxial quality and facilitate the subsequent device development. ([0027], Huang).
Regarding Claim 15, Kinoshita modified by Huang discloses the semiconductor device according to claim 14, wherein the semiconductor device comprises a power device, a radio frequency device, or a photoelectric device (a photoelectric conversion in [0021], Kinoshita).
Regarding Claim 16, Kinoshita modified by Huang discloses the semiconductor device according to claim 14, wherein the semiconductor device comprises a field-effect transistor, a light emitting diode, or a laser diode (a semiconductor light-emitting element in [0021], Kinoshita).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Kinoshita, in view of Huang and further in view of Takizawa et al. (US 20120299059 A1, hereinafter Takizawa, of the record).
Regarding Claim 3, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1,
Kinoshita modified by Huang does not expressly disclose wherein a thickness of the lower layer is greater than twice a thickness of the upper layer.
However, in the same semiconductor device field of endeavor, Takizawa wherein a thickness of the lower layer (312A made of AlGaN in [0067], Fig. 12) is greater (312A having a thickness of 400 nm and 312b having a thickness of 100 nm) than twice a thickness of the upper layer (312B made of AlGaN in [0067], Fig.12).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Takizawa’s feature of a thickness of the lower layer is greater than twice a thickness of the upper layer to the combination of Kinoshita and Huang to improve the epitaxial quality and facilitate the subsequent device development. ([0027], Huang).
Claims 5-8 are rejected under 35 U.S.C. 103 as being unpatentable over Kinoshita, in view of Huang and further in view of Inoue et al. (US 20160254378 A1, hereinafter Inoue, of the record).
Regarding Claim 5, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1,
Kinoshita modified by Huang does not expressly disclose wherein a difference between a largest band gap difference and a smallest band gap difference in the K double-layer structures is greater than 20% of a band gap difference between a group-III nitride with a largest band gap and a group-III nitride with a smallest band gap that constitute the double-layer structure.
However, in the same semiconductor device field of endeavor, Inoue discloses wherein a difference between a largest (the largest band gap difference formed when the Al content of the pairs of layers of the superlattice 4 includes x=1 and y=0 in [0038]) band gap difference and a smallest (the smallest band gap difference formed when the Al content of the pairs of layers of the superlattice 4 includes x=0.5 and y=0.3 in [0038]) band gap difference in the K double-layer structures (4 a AlGaN superlattice buffer layer 4 formed by alternately stacking the high-Al content layers with the composition of Al.sub.xGa.sub.1-xN (0.5≦x≦1.0) and the low-Al content layers with the composition Al.sub.yGa.sub.1-yN (0≦y≦0.3)in [0038]) is greater than 20% (the band gap difference is greater than of 20% of 3.2 eV, wherein 3.2 eV is obtained by the band gap difference between AlN and GaN) of a band gap difference between a group-III nitride with a largest band gap (the largest band gap of AlN corresponding to 6.2 eV) and a group-III nitride with a smallest (the smallest band gap of GaN corresponding to 3.4 eV) band gap that constitute the double-layer structure.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Inoue’s feature wherein a difference between a largest band gap difference and a smallest band gap difference in the K double-layer structures is greater than 20% of a band gap difference between a group-III nitride with a largest band gap and a group-III nitride with a smallest band gap that constitute the double-layer structure to the combination of Kinoshita and Huang to effectively reduce the warpage of the obtained nitride semiconductor epitaxial wafer ([0034], Inoue).
Regarding Claim 6, Kinoshita modified by Huang discloses the nitride epitaxial structure according to claim 1,
Kinoshita modified by Huang does not expressly disclose wherein the K double-layer structures comprise GaN and AlN, and an average Al component content in each double-layer structure is 5% to 50%.
However, in the same semiconductor device field of endeavor, Inoue discloses wherein the K double-layer structures (4 a AlGaN superlattice buffer layer in [0038]) comprise GaN and AlN, and an average Al component content in each double-layer structure is 5% to 50% (4 formed by alternately stacking the high-Al content layers with the composition of Al.sub.xGa.sub.1-xN (0.5≦x≦1.0) and the low-Al content layers with the composition Al.sub.yGa.sub.1-yN (0≦y≦0.3), wherein x=1 and y=0, the average Al content is 50% in [0038]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Inoue’s feature wherein the K double-layer structures comprise GaN and AlN, and an average Al component content in each double-layer structure is 5% to 50% to the combination of Kinoshita and Huang to effectively reduce the warpage of the obtained nitride semiconductor epitaxial wafer ([0034], Inoue).
Regarding Claim 7, Kinoshita modified by Huang and Inoue discloses nitride epitaxial structure according to claim 6,
Kinoshita modified by Huang and Inoue does not expressly disclose wherein the average Al component content in each double-layer structure is the same.
However, in the same semiconductor device field of endeavor, Huang discloses wherein the average Al component content in each double-layer structure (a superlattice a first laminated layer having a plurality of AlN layers (Al 100% constant) and a plurality of Al.sub.xGa.sub.1-xN layers (Al x% constant) that are alternately stacked in [0026], Huang) is the same (the Al content in each plurality of alternative layers is constant then the average Al component content is the same in [0026], Huang).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the Huang’s feature wherein the average Al component content in each double-layer structure is the same to the combination of Kinoshita, Huang and Inoue to tune the optical-electrical properties of the materials.
Regarding Claim 8, Kinoshita modified by Huang and Inoue discloses nitride epitaxial structure according to claim 6, wherein average Al component contents of the K double-layer structures (pairs of 13A, Kinoshita) present a gradient (the well layer having an Al composition reduced, stepwise toward the active layer 14 [0071], Kinoshita) trend along the thickness direction of the buffer layer (13A, Kinoshita).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Miyoshi (US 20170012166 A1) teaches “SEMICONDUCTOR LIGHT-EMITTING ELEMENT”. This document is related to a semiconductor light-emitting element including a superlattice composed of GaN/InGaN.
Sugiyama et al. (US 20140361337 A1) teaches “SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE”. This document is related to a HEMT device including a plurality of composition layers, each one first layers made of AlN, second layers made of a group-III nitride having a composition of Al.sub.x2Ga.sub.1-x2N having gradually decreasing thicknesses.
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 SANDRA MILENA RODRIGUEZ VILLANUEVA whose telephone number is (571)272-1936. The examiner can normally be reached Monday to Friday 7:00am-5:00pm (EST).
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/SANDRA MILENA RODRIGUEZ VILLANUEVA/Examiner, Art Unit 2898
/AJAY OJHA/Supervisory Patent Examiner, Art Unit 2898
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