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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicants’ submission filed on August 10, 2026, has been entered.
Information Disclosure Statement
The listing of references in the specification is not a proper information disclosure statement. 37 CFR 1.98(b) requires a list of all patents, publications, or other information submitted for consideration by the Office, and MPEP § 609.04(a) states, "the list may not be incorporated into the specification but must be submitted in a separate paper." Therefore, unless the references have been cited by the examiner on form PTO-892, they have not been considered.
Claim Objections
The previous objections to claims 1, 10, and 17 are withdrawn in view of applicants’ claim amendments.
Claims 1, 3, 7, 12, and 15 are objected to because of the following informalities:
The recitation of “AIN” in 10 of claim 1should be corrected to “AlN” as in the capital letter for “i” should be replaced with the lowercase letter “l.”
The recitation of “NH3” in claims 3 and 12 should be corrected to “NH3” to address an error in representing chemical formulas.
The recitation of “b-Ga203” in claim 7 should be corrected to “b-Ga2O3” to address a spelling error. It appears there is a zero instead of the letter “O” in the chemical formula.
In claim 15 the recitation of “B-Ga2O3” should be corrected to “b-Ga2O3” to address a typographical error.
Claim Interpretation
The term “about” in at least claims 2, 5, 11, and 14 is interpreted in light of ¶[0040] of the published application as encompassing ±10% of the recited value(s).
In claims 3 and 12, the recitation of “NH3” and “TMA” is interpreted as referring to the “ammonia” and “trimethylaluminum” recited in claims 1 and 10, respectively.
Claim Rejections - 35 USC § 112
Except as detailed infra, the preceding 35 U.S.C. 112(b) rejections of claims 1-18 are withdrawn.
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 1-9 and 14-15 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 pre-AIA the applicant regards as the invention.
Claim 1 recites forming “an aluminum nitride layer on the at least one sapphire template by pulsed mode growth of an AlN buffer layer.” It is unclear whether the AlN buffer layer is the same layer as the previously recited aluminum nitride layer or if they somehow are two separate AlN layers. The Examiner suggests deletion of the aspect of claim 1 which recites “of an AIN buffer layer” since providing two different labels for the same aluminum nitride layer creates ambiguity in the claim and does not clarify the metes and bounds of patent protection that are being sought. For examination purposes it is assumed that a single AlN layer is deposited as “an aluminum nitride layer” and “an AlN buffer layer” refer to the exact same layer. Dependent claims 2-9 are similarly rejected due to their direct or indirect dependence on claim 1.
Claim 4 depends from claim 1 and recites “at least one b-Ga2O3 layer“ in l. 2. It is unclear whether this is the same monoclinic phase-pure b-Ga2O3 layer as that recited in claim 1 or a different b-Ga2O3 layer. Moreover, since claim 1 already recites that a SiOx complex phase-stabilizes the gallium oxide layer it is unclear how the recitation that the gallium oxide layer is “phase-stabilized by SiOx complex formation” in claim 4 further defines the claim. It is assumed applicants intended to recite “the at least one monoclinic phase-pure b-Ga2O3 layer.” Claims 5-7 are similarly rejected due to their dependence on claim 4.
Claim 5 depends indirectly from claim 1 and recites “at least one b-Ga2O3 layer comprises monoclinic phase-pure gallium oxide“ in ll. 1-2. It is unclear whether this is the same monoclinic phase-pure b-Ga2O3 layer as that recited in claim 1 or a different b-Ga2O3 layer. Moreover, since claim 1 already recites that the b-Ga2O3 layer is monoclinic and phase-pure it is unclear how the recitation that the b-Ga2O3 layer “comprises monoclinic phase-pure gallium oxide” in claim 5 further defines the claim. It is assumed applicants intended to recite just “the at least one monoclinic phase-pure b-Ga2O3 layer.”
Claim 6 recites “the at least one b-Ga2O3 layer“ in l. 2. It is unclear whether this is the same monoclinic phase-pure b-Ga2O3 layer as that recited in claim 1 or a different b-Ga2O3 layer. It is assumed applicants intended to recite “the at least one monoclinic phase-pure b-Ga2O3 layer.”
Claim 7 recites “the at least one b-Ga2O3 layer“ in l. 2. It is unclear whether this is the same monoclinic phase-pure b-Ga2O3 layer as that recited in claim 1 or a different b-Ga2O3 layer. It is assumed applicants intended to recite “the at least one monoclinic phase-pure b-Ga2O3 layer.”
Claim 8 recites “the at least one b-Ga2O3 layer“ in l. 2. It is unclear whether this is the same monoclinic phase-pure b-Ga2O3 layer as that recited in claim 1 or a different b-Ga2O3 layer. It is assumed applicants intended to recite “the at least one monoclinic phase-pure b-Ga2O3 layer.”
Claim 14 depends indirectly from claim 10 and recites that the at least one b-Ga2O3 layer “comprises monoclinic phase-pure gallium oxide“ in l. 2. Since claim 10 already recites that the b-Ga2O3 layer is monoclinic and phase-pure it is unclear how the recitation that the b-Ga2O3 layer “comprises monoclinic phase-pure gallium oxide” in claim 14 further defines the claim.
Claim 15 depends indirectly from claim 10 and recites “forming a SiOx complex in the at least one B-Ga2O3 layer via the introduction of silane” in ll. 1-2 and “the SiOx complex” in l. 4. It is unclear whether the SiOx complex is the same as or different from the “SiOx complex phase stabilizer” recited in claim 10.
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), fourth paragraph:
Subject to the [fifth paragraph of 35 U.S.C. 112 (pre-AIA )], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 6 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 6 depends from claim 4 which further depends from claim 1 and recites “forming at least one SiOx complex in the at least one b-Ga2O3 via the introduction of silane into the metal-organic chemical vapor deposition reactor contemporaneous with the introduction of the Triethylgallium and the oxygen, wherein the SiOx complex acts as a monoclinic phase stabilizer for the b-Ga2O3.” However, since amended claim 1 appears to recite the exact same limitations, but with slightly different wording the limitations recited in claim 6 do not appear to further limit the claims from which it depends. Applicants may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
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(s) 1-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent Appl. Publ. No. 2020/0312660 to Manijeh Razeghi (hereinafter “Razeghi”) in view of a publication to S. Hasan, et al. entitled “Growth evolution of high-quality MOCVD aluminum nitride using nitrogen as carrier gas on the sapphire substrate,” Journal of Materials Research, Vol. 36, Issue 21, pp. 436-69 (2021) (“Hasan”) and further in view of a publication to D. Gogova, et al. entitled “Structural properties of Si-doped b-Ga2O3 layers grown by MOVPE,” Journal of Crystal Growth, Vol. 401, pp. 665-69 (2014) (“Gogova”).
Regarding claim 1, Razeghi teaches a method for growing Ga2O3 on sapphire (see the Abstract, Figs. 1-9, and entire reference which teach a method for growing Ga2O3 on sapphire substrates) comprising:
employing a metal–organic chemical vapor deposition reactor (see Figs. 2A-B & 4A-B, ¶[0019], and Examples 1-2 in ¶¶[0036]-[0060] which teach utilizing a MOCVD reactor);
introducing at least one sapphire template to the metal–organic chemical vapor deposition reactor (see Fig. 2A, ¶[0030, and Examples 1-2 in ¶¶[0036]-[0060] which teach the use of a sapphire substrate which is introduced to the MOCVD reactor);
introducing Triethylgallium as a gallium precursor and oxygen as an oxygen precursor; using nitrogen as a carrier gas in the metal–organic chemical vapor deposition reactor to form at least one gallium oxide layer on the layer (see Figs. 2A-B & 4A-B, ¶¶[0020]-[0024], and Examples 1-2 in ¶¶[0036]-[0060] which teach the use of TEGa as a Ga precursor, O2 gas as an oxygen precursor, and N2 as a carrier gas to deposit Ga2O3 on the substrate); and
employing silane in the metal–organic chemical vapor deposition reactor as a silicon precursor contemporaneous with introduction of the Triethylgallium and the oxygen in the metal–organic chemical vapor deposition reactor (see ¶[0022] and Examples 1-2 in ¶¶[0036]-[0060] which teach the use of silane (SiH4) during growth of the Ga2O3 layer),
wherein the method does not include post-growth thermal annealing (see Examples 1-2 in ¶¶[0036]-[0060] which teach that the MOCVD growth method does not include thermal annealing after forming the β-Ga2O3 layer).
Razeghi does not teach using nitrogen as a carrier gas to enable nitridation of the sapphire substrate and introducing Trimethylaluminum as an aluminum precursor and ammonia as a nitride precursor to the reactor to form an aluminum nitride layer on the at least one sapphire template by pulsed mode growth of an AlN buffer layer. However, in the Abstract, Figs. 1-8, as well as the Experimental and Results section at pp. 4361-69 Hasan teaches a method of growing a high quality AlN layer on a sapphire substrate using nitrogen as a carrier gas. As detailed specifically in the Abstract, Fig. 8, and the Experimental Methods section at pp. 4366-67, nitrogen is used as a carrier gas and the surface of the sapphire substrate is initially nitrided at 970 °C for 2 min. This is followed by the growth of an AlN layer by MOCVD using trimethylaluminum and ammonia as precursor gases by a two-step method in which an initial rough AlN layer is formed by pulsed growth in order to yield a high quality AlN epitaxial layer on sapphire. Thus, a person of ordinary skill in the art prior to the effective filing date of the invention would be motivated to utilize the surface nitridation and pulsed AlN growth method of Hasan to produce a high quality AlN layer as part of a two-step process for growing a high quality and thick AlN layer on the sapphire substrate utilized for Ga2O3 growth in the method of Razeghi in order to benefit from the use of a high quality crystalline substrate which is suitable for high power devices due to its higher thermal conductivity.
Razeghi and Hasan do not explicitly teach that employing silane in the metal-organic chemical vapor reactor as a silicon precursor forms a SiOx complex that phase-stabilizes the at least one gallium oxide layer as an at least one monoclinic phase-pure b-Ga2O3 layer. However, in Figs. 2A & 4A and ¶[0043] of Example 2 Razeghi teaches that the gallium oxide layer includes a β-Ga2O3 layer which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Then in ¶[0027] and Examples 1-2 in ¶¶[0036]-[0060] Razeghi teaches that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer. In this case the presence of both Si- and O-containing precursors during film growth will necessarily produce at least one SiOx complex which phase-stabilizes the at least one β-Ga2O3 layer as a monoclinic phase-pure β-Ga2O3 layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely that the β-Ga2O3 layer is phase-stabilized as a monoclinic phase-pure β-Ga2O3 layer by SiOx complex formation as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, phase-stabilization of the β-Ga2O3 layer as a monoclinic phase-pure β-Ga2O3 layer by SiOx complex formation, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).
Even if it is assumed arguendo, that Razeghi and Hasan do not teach that employing silane as a silicon precursor forms a SiOx complex that phase-stabilizes the at least one gallium oxide layer, this would have been obvious in view of the teachings of Gogova. In at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices. The combination of prior art elements according to known methods to yield predictable results has been held to support a prima facie determination of obviousness. All the claimed elements are known in the prior art and one skilled in the art could combine the elements as claimed by known methods with no change in their respective functions, with the combination yielding nothing more than predictable results to one of ordinary skill in the art. KSR International Co. v. Teleflex Inc., 550 U.S. 398, __, 82 USPQ2d 1385, 1395 (2007). See also, MPEP 2143(A).
Regarding claim 2, Razeghi teaches that a reactor pressure and a substrate temperature are kept constant throughout growth at about 50 Torr and about 700 °C (see ¶[0030] and Examples 1-2 in ¶¶[0036]-[0060] which teach that a constant temperature of 600 to 1,000 °C and pressure of 50 to 150 mbar (i.e., 37.5 to 112.5 Torr) are used during Ga2O3 growth).
Regarding claim 3, Razeghi does not teach that the aluminum nitride layer is formed via pulsed mode growth by turning NH3 on/off for 6/12 s while maintaining continuous TMA flow. However, in Fig. 8 and the Experimental methods section at pp. 4366-67 Hasan teaches that the AlN layer is produced by a two-step method in which an initial rough AlN layer is formed by pulsed growth in which the NH3 flow was turned on and off for 6 and 12 s while the TMAl flow is maintained constant. Thus, a person of ordinary skill in the art prior to the effective filing date of the invention would be motivated to produce the AlN layer via a pulsed growth mode in which the NH3 flow was turned on and off for 6 and 12 s while the TMAl flow is maintained constant as part of a two-step process for growing a high quality and thick AlN layer on the sapphire substrate.
Regarding claim 4, Razeghi and Hasan do not explicitly teach that the at least one gallium oxygen layer comprises at least one β-Ga2O3 layer formed on the aluminum nitride layer and phase-stabilized by SiOx complex formation. However, Figs. 2A & 4A and ¶[0043] of Example 2 of Razeghi teach that the gallium oxide layer includes a β-Ga2O3 layer which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Then in ¶[0027] and Examples 1-2 in ¶¶[0036][0060] Razeghi teaches that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer. In this case the presence of both Si- and O-containing precursors during film growth will necessarily produce at least one SiOx complex which phase-stabilizes the at least one β-Ga2O3 layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely that the β-Ga2O3 layer is phase-stabilized by SiOx complex formation as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, phase-stabilization of the β-Ga2O3 layer by SiOx complex formation, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach that the at least one gallium oxygen layer comprises at least one β-Ga2O3 layer formed on the aluminum nitride layer and phase-stabilized by SiOx complex formation, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claim 1, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Regarding claim 5, Razeghi and Hasan do not explicitly teach that the at least one β-Ga2O3 layer comprises monoclinic phase-pure gallium oxide on the aluminum nitride layer. However, in Figs. 1A & 4A and ¶[0043] Razeghi teaches that the deposited Ga2O3 layer shows only X-ray diffraction peaks synonymous with the presence of monoclinic pure-phase β-Ga2O3 which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely the formation of a β-Ga2O3 layer comprised of monoclinic phase-pure gallium oxide on the AlN layer. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the formation of a β-Ga2O3 layer comprised of monoclinic phase-pure gallium oxide on the AlN layer, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach that the at least one β-Ga2O3 layer comprises monoclinic phase-pure gallium oxide, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claims 1 and 4, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Razeghi, Hasan, and Gogova do not teach that the β-Ga2O3 layer has a thickness of about 580 nm. However, in at least Fig. 6, ¶[0043], and ¶[0045] Razeghi teaches an embodiment in which the Ga2O3 layer is deposited to a thickness of 150 nm while Section 2.1 of Gogova teaches that the thickness of the β-Ga2O3:Si layers was varied in the 80 to 250 nm range. Since deposition parameters such as the growth duration, precursor flow rates, substrate temperature, and chamber pressure determine the total deposited film thickness it therefore would have been within the capabilities of a PHOSITA prior to the effective filing date of the invention to optimize the growth conditions, including extending the duration of film growth to produce a β-Ga2O3 layer having a thickness of about 580 nm for use as a wide bandgap semiconductor in a specific application which requires that specific layer thickness.
Regarding claim 6, Razeghi teaches forming the at least one β-Ga2O3 by introducing silane into the metal–organic chemical vapor deposition reactor contemporaneous with the introduction of the Triethylgallium and the oxygen (see ¶[0027] and Examples 1-2 in ¶¶[0036]-[0060] which teach that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer), but does not teach forming at least one SiOx complex in the at least one β-Ga2O3, wherein the SiOx complex acts as a monolithic phase stabilizer for the β-Ga2O3. However, the presence of both Si- and O-containing precursors during film growth in the method of Razeghi will necessarily produce at least one SiOx complex in the at least one β-Ga2O3 layer which acts as a monolithic phase stabilizer for the β-Ga2O3. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely the formation of at least one SiOx complex as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the formation of at least one SiOx complex which acts as a monolithic phase stabilizer for the β-Ga2O3, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach the formation of at least one SiOx complex which acts as a monoclinic phase stabilizer for the β-Ga2O3 layer, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claims 1 and 4-5, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Regarding claim 7, Razeghi, Hasan, and Gogova teach forming sixfold inplane rotational symmetry in the at least one β-Ga2O3 layer formed on the aluminum nitride layer (see Figs. 4A-B and at least ¶[0043] of Example 2 of Razeghi which teaches that the β-Ga2O3 layer has 6 rotated domains which will necessarily form upon being deposited onto the AlN layer of Hasan), but do not explicitly teach that this is measured by six {401}-plane peaks separated by about 60° in an XRD j-scan. However, since the method taught by the combination of Razeghi, Hasan, and Gogova performs each and every step of the claimed process it must necessarily produce the same results, namely a sixfold in-plane rotational symmetry in the β-Ga2O3 layer formed on the aluminum nitrogen layer as measured by six {401}-plane peaks separated by about 60° in an XRD j-scan. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the presence of sixfold in-plane rotational symmetry in the β-Ga2O3 layer formed on the aluminum nitrogen layer as measured by six {401}-plane peaks separated by about 60° in an XRD j-scan, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).
Regarding claim 8, Razeghi teaches that the method does not include thermal annealing after formation of the at least one β-Ga2O3 layer, thereby avoiding Al diffusion from the sapphire substrate into the gallium oxide layer (see Examples 1-2 in ¶¶[0036]-[0060] which teach that the MOCVD growth method does not include thermal annealing after forming the β-Ga2O3 layer which will necessarily avoid Al diffusion as claimed).
Regarding claim 9, Razeghi teaches that the sapphire template comprises c-plane sapphire (see Example 1 at ¶¶[0036]-[0039] which teaches the use of c-plane sapphire), but does not teach that the sapphire has a 0.2° miscut. However, in Fig. 2 and the Experimental and Results section at pp. 4361-69 Hasan teaches that the sapphire substrate used for AlN growth has a 0.2° miscut towards the m-plane. Thus, a PHOSITA prior to the effective filing date of the invention would be motivated to utilize a 0.2° miscut sapphire substrate for AlN and Ga2O3 growth in order to provide a terraced surface in order to control the growth mode and produce the desired surface morphology during film growth.
Regarding claim 10, Razeghi teaches a method for growing Ga2O3 layers on sapphire (see the Abstract, Figs. 1-9, and entire reference which teach a method for growing Ga2O3 on sapphire substrates) comprising:
employing a metal–organic chemical vapor deposition reactor (see Figs. 2A-B & 4A-B, ¶[0019], and Examples 1-2 in ¶¶[0036]-[0060] which teach utilizing a MOCVD reactor);
introducing at least one sapphire template to the metal–organic chemical vapor deposition reactor (see Fig. 2A, ¶[0030, and Examples 1-2 in ¶¶[0036]-[0060] which teach the use of a sapphire substrate which is introduced to the MOCVD reactor);
introducing Triethylgallium as a gallium precursor and oxygen as an oxygen precursor using nitrogen as a carrier gas in the metal–organic chemical vapor deposition reactor to form at least one β-Ga2O3 gallium oxide layer (see Figs. 2A-B & 4A-B, ¶¶[0020]-[0024], and Examples 1-2 in ¶¶[0036]-[0060], including specifically ¶[0043] which teach the use of TEGa as a Ga precursor, O2 gas as an oxygen precursor, and N2 as a carrier gas to deposit β-Ga2O3 on the substrate); and
employing silane in the metal–organic chemical vapor deposition reactor as a silicon precursor contemporaneous with introduction of the Triethylgallium and the oxygen in the metal–organic chemical vapor deposition reactor to form the β-Ga2O3 gallium oxide layer (see ¶[0022] and Examples 1-2 in ¶¶[0036]-[0060] which teach the use of silane (SiH4) during growth of the Ga2O3 layer which, due to the presence of both Si- and O-containing precursors during growth of the β-Ga2O3 gallium oxide layer),
wherein the method does not include post-growth thermal annealing (see Examples 1-2 in ¶¶[0036]-[0060] which teach that the MOCVD growth method does not include thermal annealing after forming the β-Ga2O3 layer).
Razeghi does not teach using nitrogen as a carrier gas to enable nitridation of the sapphire substrate and forming at least one substrate layer onto the sapphire substrate wherein the at least one substrate layer comprises an aluminum nitride layer formed by pulsed mode growth. However, in the Abstract, Figs. 1-8, as well as the Experimental and Results section at pp. 4361-69 Hasan teaches a method of growing a high quality AlN layer on a sapphire substrate using nitrogen as a carrier gas. As detailed specifically in the Abstract, Fig. 8, and the Experimental Methods section at pp. 4366-67, nitrogen is used as a carrier gas and the surface of the sapphire substrate is initially nitrided at 970 °C for 2 min. This is followed by the growth of an AlN layer by MOCVD using trimethylaluminum and ammonia as precursor gases by a two-step method in which an initial rough AlN layer is formed by pulsed growth in order to yield a high quality AlN epitaxial layer on sapphire. Thus, a person of ordinary skill in the art prior to the effective filing date of the invention would be motivated to utilize the surface nitridation and pulsed AlN growth method of Hasan to produce a high quality AlN layer as part of a two-step process for growing a high quality and thick AlN layer on the sapphire substrate utilized for Ga2O3 growth in the method of Razeghi in order to benefit from the use of a high quality crystalline substrate which is suitable for high power devices due to its higher thermal conductivity.
Razeghi and Hasan do not explicitly teach that employing silane in the metal-organic chemical vapor reactor as a silicon precursor forms a SiOx complex that phase-stabilizes the at least one gallium oxide layer as an at least one monoclinic phase-pure b-Ga2O3 layer. However, in Figs. 2A & 4A and ¶[0043] of Example 2 Razeghi teaches that the gallium oxide layer includes a β-Ga2O3 layer which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Then in ¶[0027] and Examples 1-2 in ¶¶[0036]-[0060] Razeghi teaches that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer. In this case the presence of both Si- and O-containing precursors during film growth will necessarily produce at least one SiOx complex which phase-stabilizes the at least one β-Ga2O3 layer as a monoclinic phase-pure β-Ga2O3 layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely that the β-Ga2O3 layer is phase-stabilized as a monoclinic phase-pure β-Ga2O3 layer by SiOx complex formation as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, phase-stabilization of the β-Ga2O3 layer as a monoclinic phase-pure β-Ga2O3 layer by SiOx complex formation, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).
Even if it is assumed arguendo, that Razeghi and Hasan do not teach that employing silane as a silicon precursor forms a SiOx complex that phase-stabilizes the at least one β-Ga2O3 gallium oxide layer such that it is monoclinic phase-pure, this would have been obvious in view of the teachings of Gogova. In at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices. The combination of prior art elements according to known methods to yield predictable results has been held to support a prima facie determination of obviousness. All the claimed elements are known in the prior art and one skilled in the art could combine the elements as claimed by known methods with no change in their respective functions, with the combination yielding nothing more than predictable results to one of ordinary skill in the art. KSR International Co. v. Teleflex Inc., 550 U.S. 398, __, 82 USPQ2d 1385, 1395 (2007). See also, MPEP 2143(A).
Regarding claim 11, Razeghi teaches that a reactor pressure and a substrate temperature are kept constant throughout growth at about 50 Torr and about 700 °C (see ¶[0030] and Examples 1-2 in ¶¶[0036]-[0060] which teach that a constant temperature of 600 to 1,000 °C and pressure of 50 to 150 mbar (i.e., 37.5 to 112.5 Torr) are used during Ga2O3 growth).
Regarding claim 12, Razeghi does not teach that the aluminum nitride layer is formed via pulsed mode growth by turning NH3 on/off for 6/12 s while maintaining continuous TMA flow. However, in Fig. 8 and the Experimental methods section at pp. 4366-67 Hasan teaches that the AlN layer is produced by a two-step method in which an initial rough AlN layer is formed by pulsed growth in which the NH3 flow was turned on and off for 6 and 12 s while the TMAl flow is maintained constant. Thus, a person of ordinary skill in the art prior to the effective filing date of the invention would be motivated to produce the AlN layer via a pulsed growth mode in which the NH3 flow was turned on and off for 6 and 12 s while the TMAl flow is maintained constant as part of a two-step process for growing a high quality and thick AlN layer on the sapphire substrate.
Regarding claim 13, Razeghi and Hasan do not explicitly teach that the at least one β-Ga2O3 gallium oxygen layer comprises at least one β-Ga2O3 layer formed on the aluminum nitride layer with SiOx phase stabilization. However, Figs. 2A & 4A and ¶[0043] of Example 2 of Razeghi teach that the gallium oxide layer includes a β-Ga2O3 layer which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Then in ¶[0027] and Examples 1-2 in ¶¶[0036][0060] Razeghi teaches that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer. In this case the presence of both Si- and O-containing precursors during film growth will necessarily produce at least one SiOx complex which phase-stabilizes the at least one β-Ga2O3 layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely that the β-Ga2O3 layer is phase-stabilized by SiOx complex formation as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, phase-stabilization of the β-Ga2O3 layer by SiOx complex formation, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach that the at least one β-Ga2O3 gallium oxygen layer comprises at least one β-Ga2O3 layer formed on the aluminum nitride layer with SiOx phase stabilization, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claim 10, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Regarding claim 14, Razeghi and Hasan do not explicitly teach that the at least one β-Ga2O3 layer comprises monoclinic phase-pure gallium oxide on the aluminum nitride layer. However, in Figs. 1A & 4A and ¶[0043] Razeghi teaches that the deposited Ga2O3 layer shows only X-ray diffraction peaks synonymous with the presence of monoclinic pure-phase β-Ga2O3 which, when utilized in combination with the AlN buffer layer of Hasan, will necessarily be formed on an AlN layer. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely the formation of a β-Ga2O3 layer comprised of monoclinic phase-pure gallium oxide on the AlN layer. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the formation of a β-Ga2O3 layer comprised of monoclinic phase-pure gallium oxide on the AlN layer, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach that the at least one β-Ga2O3 layer comprises monoclinic phase-pure gallium oxide, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claims 10 and 13, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Razeghi, Hasan, and Gogova do not teach that the β-Ga2O3 layer has a thickness of about 580 nm. However, in at least Fig. 6, ¶[0043], and ¶[0045] Razeghi teaches an embodiment in which the Ga2O3 layer is deposited to a thickness of 150 nm while Section 2.1 of Gogova teaches that the thickness of the β-Ga2O3:Si layers was varied in the 80 to 250 nm range. Since deposition parameters such as the growth duration, precursor flow rates, substrate temperature, and chamber pressure determine the total deposited film thickness it therefore would have been within the capabilities of a PHOSITA prior to the effective filing date of the invention to optimize the growth conditions, including extending the duration of film growth to produce a β-Ga2O3 layer having a thickness of about 580 nm for use as a wide bandgap semiconductor in a specific application which requires that specific layer thickness.
Regarding claim 15, Razeghi teaches forming the at least one β-Ga2O3 by introducing silane into the metal–organic chemical vapor deposition reactor contemporaneous with the introduction of the Triethylgallium and the oxygen (see ¶[0027] and Examples 1-2 in ¶¶[0036]-[0060] which teach that silane is introduced into the reactor together with the gallium and oxygen precursor gases to form a doped β-Ga2O3 layer), but does not teach forming at least one SiOx complex in the at least one β-Ga2O3 layer, wherein the SiOx complex passivates gallium vacancies and acts as a phase stabilizer. However, the presence of both Si- and O-containing precursors during film growth in the method of Razeghi will necessarily produce at least one SiOx complex in the at least one β-Ga2O3 layer which acts as a monolithic phase stabilizer for the β-Ga2O3. Alternatively, since the method taught by the combination of Razeghi and Hasan performs each and every step of the claimed process it must necessarily produce the same results, namely the formation of at least one SiOx complex which passivates Ga vacancies and acts as a phase stabilizer as claimed. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the formation of at least one SiOx complex which passivates Ga vacancies and acts as a monolithic phase stabilizer, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).).
Even if it is assumed arguendo that Razeghi and Hasan do not teach the formation of at least one SiOx complex which passivates Ga vacancies and acts as a phase stabilizer, this would have been obvious in view of the teachings of Gogova. As noted supra with respect to the rejection of claims 1 and 4-5, in at least the Abstract, Figs. 1-3, the Experimental and Results sections in Sections 2 and 3.1-3.2 Gogova teaches an analogous method of depositing a β-Ga2O3 layer onto a sapphire substrate by metalorganic vapor phase epitaxy using TMG and water vapor as precursors along with TEOS as a silicon source. As shown specifically in Fig. 3, Section 3.2.1, and the Conclusion, Gogova teaches that doping the Ga2O3 layer with Si in certain concentrations (curves (a) and (b)) leads to the formation of a monoclinic pure-phase β-Ga2O3 layer with diffraction peaks caused by the -402, -603, and -804 Bragg reflections. Thus, a PHOSITA prior to the effective filing date of the invention would look to the teachings of Gogova and would be motivated to utilize routine experimentation to determine the optimal Si dopant concentration in the method of Razeghi and Hasan that results in the formation of one or more SiOx complexes that passivate Ga vacancies and phase stabilize the gallium oxide layer into a monoclinic phase-pure β-Ga2O3 layer in order to produce a higher quality large-bandgap material suitable for applications in electronic and optoelectronic devices.
Regarding claim 16, Razeghi, Hasan, and Gogova teach forming sixfold inplane rotational symmetry in the at least one β-Ga2O3 layer formed on the aluminum nitride layer (see Figs. 4A-B and at least ¶[0043] of Example 2 of Razeghi which teaches that the β-Ga2O3 layer has 6 rotated domains which will necessarily form upon being deposited onto the AlN layer of Hasan), but do not explicitly teach that this is measured by six {401}-plane peaks of the at least one β-Ga2O3 layer which are aligned with six {102}-plane peaks of the aluminum nitride layer. However, since the method taught by the combination of Razeghi, Hasan, and Gogova performs each and every step of the claimed process it must necessarily produce the same results, namely the formation of six {401}-plane peaks of the at least one β-Ga2O3 layer which are aligned with six {102}-plane peaks of the aluminum nitride layer. It is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art. Therefore, the presence of in-plane rotational symmetry in the β-Ga2O3 layer formed on the aluminum nitrogen layer with six {401}-plane peaks of the at least one β-Ga2O3 layer which are aligned with six {102}-plane peaks of the aluminum nitride layer, if not clearly envisaged, would be reasonably expected by the skilled artisan. See Leinoff v. Louis Milona & Sons, Inc. 220 USPQ 845 (CAFC 1984).
Regarding claim 17, Razeghi teaches that the method does not include thermal annealing after growth of the at least one β-Ga2O3 layer so as to avoid formation of β-(AlxGa1-x)2O3 by Al diffusion from sapphire (see Examples 1-2 in ¶¶[0036]-[0060] which teach that the MOCVD growth method does not include thermal annealing after forming the β-Ga2O3 layer which will necessarily avoid diffusion from sapphire and the formation of β-(AlxGa1-x)2O3 as claimed).
Regarding claim 18, Razeghi teaches that the sapphire template comprises c-plane sapphire (see Example 1 at ¶¶[0036]-[0039] which teaches the use of c-plane sapphire), but does not teach that the sapphire has a 0.2° miscut. However, in Fig. 2 and the Experimental and Results section at pp. 4361-69 Hasan teaches that the sapphire substrate used for AlN growth has a 0.2° miscut towards the m-plane. Thus, a PHOSITA prior to the effective filing date of the invention would be motivated to utilize a 0.2° miscut sapphire substrate for AlN and Ga2O3 growth in order to provide a terraced surface in order to control the growth mode and produce the desired surface morphology during film growth.
Response to Arguments
Applicant's arguments filed August 10, 2026, have been fully considered, but they are not persuasive and are moot in view of the new grounds of rejection set forth in this Office Action. A publication to D. Gogova, et al. entitled “Structural properties of Si-doped b-Ga2O3 layers grown by MOVPE,” Journal of Crystal Growth, Vol. 401, pp. 665-69 (2014) has been introduced in support of the Examiner’s position and to teach the newly added claim limitations.
Except as set forth supra, the previous 35 U.S.C. 112(b) rejections of claims 1-18 are withdrawn in view of applicants’ arguments and claim amendments.
Applicants argue that Razeghi and Hasan do not teach the production of a SiOx complex which phase-stabilizes monoclinic pure-phase β-Ga2O3 as a result of adding silane because this is a possible rather than a necessary result, it is legally and factually insufficient, and there is no reasonable expectation of success from the proposed combination while simultaneously avoiding post-growth thermal annealing. See applicants’ 8/10/2026 reply, pp. 11-16. Applicants’ arguments are noted, but are unpersuasive and are moot in view of the new grounds of rejection set forth in this Office Action. First it is noted that at least ¶[0081] of the published application specifically refers to the Gogova publication which teaches that Si has a strong affinity for oxygen which results in the formation of SiOx complexes in β-Ga2O3 due to the compensation of Si by Ga vacancies. Thus, the presence of Si during growth of the Ga2O3 layer will necessarily produce at least one SiOx complex (i.e., SiO, SiO2, etc.) due to the abundance of oxygen in the crystal lattice and the strong affinity for a bond to form between Si and O atoms. In any case, applicants’ arguments are moot in view of the teachings of Gogova which have been introduced to teach the newly added claim limitations and to affirm the Examiner’s position by specifically showing that SiOx complexes form during MOCVD growth of Ga2O3 thin films.
Applicants then argue against the rejection of claims 5 and 14 by contending that the claimed thickness of about 580 nm cannot be treated as a mere routine optimization divorced from the phase-purity and SiOx stabilization limitations due to an increase in surface roughness with thickness. Id. at p. 17. Applicants’ argument is noted, but is unpersuasive. First, it is pointed out that the claims do not specify the roughness of the film, so arguments relating to an increase in roughness preventing an increase in thickness are based upon features which are not claimed. Second, it is noted that in Section 2.1 Gogova specifically teaches the growth of layers with a thickness of up to 250 nm and there is no teaching or suggestion that there is an upper limit. Thus, applicants’ arguments appear to be based on arguments of counsel rather than factually supported objective evidence. It is the Examiner’s position that the desired thickness may be obtained by simply increasing or prolonging the deposition time until the desired total thickness of “about 580 nm” is attained.
Applicants then repeat their argument against the rejection of claims 6 & 15 and 7 & 16 by contending that the mere presence of Si and O is not enough to produce the claimed SiOx complex and that Razeghi’s sapphire-grown domains do not exhibit the sixfold inplane rotational symmetry as a result of growth on an AlN nitride layer instead of directly on sapphire. Id. at p. 17. These arguments remain unpersuasive for reasons noted supra and in the Response to Arguments section of the May 15, 2026, final Office Action. It is again pointed out that claims 6 and 15 merely recite “forming at least one SiOx complex in the at least one β-Ga2O3 via the introduction of silane into the reactor contemporaneous with the introduction of the triethylgallium and the oxygen.” Since the method of Razeghi simultaneously introduces silane, TEGa, and oxygen into the reactor as claimed then it must necessarily produce the same results, namely that of forming a SiOx complex. It is noted that a “SiOx complex” may be considered as merely a Si-O bond when x = 1 and the presence of Si in the deposited Ga2O3 layer will necessarily result in at least some Si-O bonds due to the stability of SiO2 and implausibility of forming only Si-Ga bonds. Additionally, the arguments are moot in view of the introduction of Gogova to clearly teach that SiOx complexes do, in fact, form the Ga2O3 layer as a result of adding Si as a dopant. With respect to the formation of sixfold inplane rotational symmetry it is noted that applicants’ argument appears to be based on arguing 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). In this case the rejection is based on the combination of Razeghi and Hasan which would then involve growing Ga2O3 on an AlN buffer layer formed on sapphire which would then produce the sixfold inplane rotational symmetry as claimed.
Applicants argue against the rejection of claims 8 and 17 by contending that the absence of an annealing step in Razeghi does not teach the claimed solution. Id. at p. 18. Applicants’ argument is noted, but is unpersuasive. It is pointed out that the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art (i.e., the lack of an annealing step) cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). In this case the combination of Razeghi, Hasan, and Gogova teach a process which does not require or utilize an annealing step. Since an annealing step is not performed, the problem of avoiding Al diffusion from the sapphire substrate into the gallium oxide layer is also avoided.
Finally, applicants comment on the rejection of claims 3, 9, 12, and 18 by contending that even if Hasan discloses aspects of AlN pulsed growth or the sapphire miscut, these teachings do not cure alleged deficiencies regarding the SiOx-stabilized monoclinic phase-pure β-Ga2O3. Id. at p. 18. Applicants’ argument is noted, but it is the Examiner’s position that the combination of Razeghi, Hasan, and now Gogova teach each and every limitation recited in independent claims 1 and 10 for reasons presented supra.
Conclusion
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/KENNETH A BRATLAND JR/Primary Examiner, Art Unit 1714
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