DETAILED ACTION
This Office Action is in response to Amendment filed November 21, 2025.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-3, 5-7, 11, 14, 15 and 20-22 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claims contain subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventors, at the time the application was filed, had possession of the claimed invention.
(1) Regarding claim 1, Applicants originally disclosed in paragraph [0073] of current application that “The total donor impurity concentration is the total sum of the concentrations of the donor impurities contained in the GaN crystal according to the first embodiment”, and that “Known examples of the impurities that act as donors for GaN include O (oxygen), Si (silicon), S (sulfur), Ge (germanium), and Sn (tin) (emphasis added).” However, Applicants did not originally disclose “a total donor impurity concentration of at least one donor impurity selected from the group consisting of O, Si, S, Ge and Sn of less than 5 × 1016 atoms/cm3 (emphasis added)” as recited on lines 8-9, because (a) while Applicants originally disclosed that the donor impurity concentration is a concentration of O, Si, S, Ge and Sn, the amended claim 1 recites that the donor impurity concentration can be a total donor impurity concentration of O, Si, S, Ge, Sn, O + Si, O + S, O + Ge, O + Sn, Si + S, Si + Ge, …, which is much broader than the original disclosure in that, as currently claimed, a concentration of O can be less than 5 × 1016 atoms/cm3, a concentration of Si can be less than 5 × 1016 atoms/cm3, a concentration of S can be less than 5 × 1016 atoms/cm3, a concentration of Ge can be less than 5 × 1016 atoms/cm3, a concentration of Sn can be less than 5 × 1016 atoms/cm3, a concentration of O + Si can be less than 5 × 1016 atoms/cm3, a concentration of O + S can be less than 5 × 1016 atoms/cm3, …, while a concentration of O, Si, S, Ge and Sn can be equal to or greater than 5 × 1016 atoms/cm3, and (b) in other words, the phrase “a total donor impurity concentration of at least one donor impurity” in the claimed range can suggest “a total donor impurity concentration of” only one donor impurity in the claimed range, which Applicants did not originally disclose, or “a total donor impurity concentration of” two or more, but not all of, donor impurities in the claimed range, which Applicants did not originally disclose, either.
(2) Further regarding claim 1, even if arguendo the claimed “total donor impurity concentration” is a total donor impurity concentration of any of O, Si, S, Ge and Sn, Applicants did not originally disclose “a total donor impurity concentration of donor impurities of at least one donor impurity selected from the group consisting of O, Si, S, Ge and Sn of less than 5 × 1016 atoms/cm3 (emphasis added)” as recited on lines 8-9, because (a) Applicants originally disclosed in paragraph [0073] of current application that “The total donor impurity concentration is the total sum of the concentrations of the donor impurities contained in the GaN crystal according to the first embodiment”, that “Known examples of the impurities that act as donors for GaN include O (oxygen), Si (silicon), S (sulfur), Ge (germanium), and Sn (tin) (emphasis added)”, in paragraph [0074] of current application that “Therefore, the GaN crystal may contain each of O (oxygen) and Si (silicon) at a concentration in the order 1015 atoms/cm3 or more even though these are not intentionally added”, that “On the other hand, donor impurities other than O and Si are present at non-negligible concentrations in the GaN crystal according to the first embodiment only in cases where doping with the donor impurities is intentional carried out (emphasis added)”, and that “The “intentional doping” means, for example, that, for doping a GaN crystal with a subject element, the subject element is added as a raw material in the state of a simple substance or a compound”, and in paragraph [0075] of current application that “Therefore, unless the crystal is intentionally doped with donor impurities other than O and Si, the total donor impurity concentration in the GaN crystal according to the first embodiment may be regarded as equal to the sum of the O concentration and the Si concentration (emphasis added)”, (b) in addition, Applicants originally disclosed in paragraph [0164] of current application that “Impurity concentrations of the c-plane single-crystal GaN substrate prepared in were measured by SIMS (emphasis added)”, and that “As a result, the Fe concentration was found to be 1.5×1018 atoms/cm3; the Si concentration was found to be 1.3×1016 atoms/cm3; the O concentration was found to be 8.0×1015 atoms/cm3; and the C concentration was found to be 3.6×1016 atoms/cm3 (emphasis added)”, and in paragraph [0176] of current application that Impurity concentrations of the c-plane single-crystal GaN substrate prepared in (1) were measured by SIMS (emphasis added)”, and that “As a result, the Fe concentration was found to be 5.4×1018 atoms/cm3; the Si concentration was found to be 1.1×1016 atoms/cm3; the O concentration was found to be 8.3×1015 atoms/cm3; and the C concentration was found to be 3.4×1016 atoms/cm3 (emphasis added), (c) therefore, while Applicants may have observed a total donor impurity concentration of O and Si as disclosed in paragraphs [0164] and [0176] of current application cited above, Applicants claim that “a total donor impurity concentration of donor impurities of at least one donor impurity selected from the group consisting of O, Si, S, Ge and Sn of less than 5 × 1016 atoms/cm3 (emphasis added)” as recited on lines 8-9 based on a conjecture that “Known examples of the impurities that act as donors for GaN include O (oxygen), Si (silicon), S (sulfur), Ge (germanium), and Sn (tin) (emphasis added)” as disclosed in paragraph [0073] of current application, (d) in other words, Applicants claim a total donor impurity concentration that may include S, Ge or Sn even though Applicants observed only O and Si as disclosed in paragraphs [0164] and [0176] of current application, (e) in addition, Applicants do not simply claim “a total donor impurity concentration” per se, but rather also claim “a (004) X-ray diffraction rocking curve full width at half maximum” as recited on lines 11-12, and (f) therefore, Applicants did not originally disclose what a (004) X-ray diffraction rocking curve full width at half maximum would be when a GaN crystal includes S, Ge or Sn as donor impurities, which Applicants did not measure themselves.
(3) Regarding claims 1 and 6, Applicants originally disclosed in paragraph [0020] of current application that “the (004) XRD rocking curve full width at half maximum measured on the (0001) surface side is less than 30 arcsec, less than 25 arcsec, less than 20 arcsec, less than 18 arcsec, less than 16 arcsec, less than 14 arcsec, or less than 12 arcsec”, in paragraph [0023] of current application that “the (004) XRD rocking curve full width at half maximum. measured on the (0001) surface side is less than 30 arcsec, less than 25 arcsec, less than 20 arcsec, less than 18 arcsec, less than 16 arcsec, less than 14 arcsec, or less than 12 arcsec”, and in paragraph [0090] of current application that “The (004) XRD rocking curve full width at half maximum measured on the (0001) surface side of the GaN crystal according to the first embodiment is preferably less than 30 arcsec, more preferably less than 25 arcsec, still more preferably less than 20 arcsec, still more preferably less than 18 arcsec, still more preferably less than 16 arcsec, still more preferably less than 14 arcsec, still more preferably less than 12 arcsec”. However, Applicants did not originally disclose “a (004) X-ray diffraction rocking curve full width at half maximum measured on the top surface of less than 30 arcsec and larger than 0 arcsec” as recited on lines 11-12 of the amended claim 1 and on lines 5-7 of the amended claim 6, because (a) Applicants did not originally disclose the lower limit of the claimed (004) X-ray diffraction rocking curve full width at half maximum, (b) the (004) X-ray diffraction rocking curve full width at half maximum Applicants observed may have been, for example, (about) 10 arcsec as Applicants originally disclosed in paragraph [0171] of current application that “An Fe-doped plane single-crystal GaN substrate was prepared by almost same procedure as in experiment except that a c-plane single-crystal GaN substrate grown an ammonothermal process using NH4F and NH4I as mineralizers, the substrate having (004) XRD rocking curve full width at half maximum of about 10 arcsec, was used as the seed, and that the flow rate of the carrier gas supplied to the vaporizer during the growth of the Fe-doped GaN layer was increased (emphasis added)”, and in paragraph [0175] of current application that “The average based on measurement at 5 positions on the sample surface with an area of 6.3 cm2 was 10 arcsec (emphasis added)”, and (c) however, the newly claimed range of the (004) X-ray diffraction rocking curve full width at half maximum can include 1 arcsec, 0.1 arcsec or 0.01 arcsec since all of 1 arcsec, 0.1 arcsec and 0.01 arcsec are “larger than 0 arcsec”.
Claims 2, 3, 5, 14 and 15 depend on claim 1, and claims 7 and 20-22 depend on claim 6, and therefore, claims 2, 3, 5, 7, 14, 15 and 20-22 also fail to comply with the written description requirement.
(4) Regarding claims 7, 11 and 22, claims 7, 11 and 22 fail to comply with the written description requirement for the same reasons stated above involving the donor impurities of O, Si, S, Ge and Sn.
(5) Regarding claim 21, Applicants originally disclosed in paragraph [0006] of current application that “It is known that semi-insulating GaN can be provided by doping with an impurity having an action that compensates n-type carriers, such as Fe (iron), Mn (manganese), or C (carbon)”, and that “Such an impurity is sometimes called a compensating impurity”, and in paragraph [0087] of current application that “The GaN crystal according to the first embodiment may also contain compensating impurities other than Fe and C, such as Mn (manganese), Co (cobalt), and Ni (nickel), as long as their inclusion does not cause a practical problem.” However, Applicants did not originally disclose that “the GaN crystal has a total concentration of at least one compensating impurity selected from the group consisting of Fe, C, Mn, Co, and Ni of not less than 5 × 1017 atoms/cm3”, because (a) Applicants did not originally disclose a plurality of the impurities such as Fe + Mn + Co, Fe + Co + Ni, C + Mn, Mn + Ni, etc. can be included in the claimed GaN crystal, and (b) Applicants did not originally disclose a plurality of the impurities such as Fe + Mn + Co, Fe + Co + Ni, C + Mn, Mn + Ni, etc. can be included in the claimed range of not less than 5 × 1017 atoms/cm” in the claimed GaN crystal.
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.
Claims 1-3, 5, 14 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Vaudo et al. (US 6,156,581) in view of Melnik et al. (US 6,936,357) and further in view of Fujisawa et al. (US 2017/0327971)
Regarding claim 1, Vaudo et al. disclose a GaN crystal (col. 9, lines 13-17 and 29-31) having a top surface having an area of not less than 5 cm2, because the two-inch wafer disclosed on lines 15-17 of column 9 corresponds to an area of π·(2.54 cm)2, which is greater than 5 cm2, wherein the top surface has an inclination of not more than 10° with respect to a (0001) crystal plane, because this claimed range includes an inclination of 0°, which is less than 10°, and the GaN crystal has a total donor impurity concentration of at least one donor impurity selected from the group consisting of O, Si, S, Ge, and Sn of less than 5×1016 atoms/cm2 (col. 12, lines 44-47 and 59-62).
Vaudo et al. differ from the claimed invention by not showing that the GaN crystal has an Fe concentration of not less than 5×1017 atoms/cm2 and less than 1×1019 atoms/cm2, and a (004) X-ray diffraction rocking curve full width at half maximum measured on the top surface of less than 30 arcsec and larger than 0 arcsec.
Melnik et al. disclose a GaN crystal (Title) where “The inventors have found that in order to achieve the desired Na /Nd ratio and grow p-type GaN or AlGaN, the concentration of the acceptor impurity must be in the range of 1018 to 10 atoms per cubic centimeter, and more preferably in the range of 1019 to 1020 atoms per cubic centimeter”, and that “For an i-type layer, the doping level must be decreased, typically such that the dopant concentration does not exceed 1019 atoms per cubic centimeter” (col. 10, lines 2-10), where the p-type or i-type dopant can be Fe (col. 9, lines 12-19).
Since both Vaudo et al. and Melnik et al. teach a GaN crystal, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that an Fe concentration in the GaN crystal disclosed by Vaudo et al. can be not less than 5×1017 atoms/cm2 and less than 1×1019 atoms/cm2, because (a) the GaN crystal disclosed by Vaudo et al. can be doped p-type or i-type to form a desired substrate or a buffer layer to in turn form a semiconductor device having desired electrical characteristics including an insulating or a semi-insulating GaN substrate or buffer layer disclosed by Melnik et al., (b) the claimed Fe concentration range overlaps with the range of Fe concentration disclosed by Melnik et al., and (c) the claim is prima facie obvious without showing that the claimed range of the Fe concentration achieves unexpected results relative to the prior art range. In re Woodruff, 16 USPQ2d 1935, 1937 (Fed. Cir. 1990). See also In re Huang, 40 USPQ2d 1685, 1688 (Fed. Cir. 1996) (claimed ranges of a result effective variable, which do not overlap the prior art ranges, are unpatentable unless they produce a new and unexpected result which is different in kind and not merely in degree from the results of the prior art). See also In re Boesch, 205 USPQ 215 (CCPA) (discovery of optimum value of result effective variable in known process is ordinarily within skill of art) and In re Aller, 105 USPQ 233 (CCPA 1955) (selection of optimum ranges within prior art general conditions is obvious).
Further regarding claim 1, Vaudo et al. in view of Melnik et al. differ from the claimed invention by not showing that the GaN crystal has a (004) XRD rocking curve full width at half maximum measured on the top surface is less than 30 arcsec and larger than 0 arcsec.
Fujisawa et al. disclose a GaN crystal where a (004) XRD rocking curve full width at half maximum measured on a surface is less than 30 arcsec ([0045]-[0046]).
Since both Vaudo et al. and Fujisawa et al. disclose a GaN crystal, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal disclosed by Vaudo et al. in view of Melnik can exhibit a (004) XRD rocking curve full width at half maximum measured on the surface that is less than 30 arcsec and larger than 0 arcsec as disclosed by Fujisawa et al., because (a) the top or bottom surface of the GaN crystal disclosed by Vaudo et al. in view of Melnik et al. can be planarized by, for example, a chemical mechanical polishing, which has been commonly employed in a semiconductor manufacturing process to obtain a semiconductor surface having an ultralow surface roughness, (b) a semiconductor surface having an ultralow surface roughness, and thus a low XRD rocking curve full width at half maximum, would allow forming a semiconductor device having excellent electrical characteristics due to less scattering of charge carriers, i.e. electrons and holes, at or near the surface of the semiconductor surface, and (c) the claim is prima facie obvious without showing that the claimed range of the (004) XRD rocking curve full width at half maximum achieves unexpected results relative to the prior art range. In re Woodruff, 16 USPQ2d 1935, 1937 (Fed. Cir. 1990). See also In re Huang, 40 USPQ2d 1685, 1688 (Fed. Cir. 1996) (claimed ranges of a result effective variable, which do not overlap the prior art ranges, are unpatentable unless they produce a new and unexpected result which is different in kind and not merely in degree from the results of the prior art). See also In re Boesch, 205 USPQ 215 (CCPA) (discovery of optimum value of result effective variable in known process is ordinarily within skill of art) and In re Aller, 105 USPQ 233 (CCPA 1955) (selection of optimum ranges within prior art general conditions is obvious).
Regarding claim 2, Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. differ from the claimed invention by not having a room-temperature resistivity of not less than 1×1011 Ω cm measured between the top surface and a bottom surface of the GaN crystal.
It would have been obvious, if not inherent, to one of ordinary skill in the art before the effective filing date of the claimed invention that a room-temperature resistivity measured between the top and bottom surface of the GaN crystal disclosed by Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. can be not less than 1×1011 Ω cm, because (a) Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. disclose all the claim limitations of claim 1, and therefore, if Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. do not disclose the claimed room-temperature resistivity, claim 2 would be further indefinite for not claiming an essential and critical feature to the practice of the claimed invention, and (c) if arguendo Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. do not disclose the claimed room-temperature resistivity, then it would at least have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal disclosed by Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. can have the claimed room-temperature resistivity by controlling the total donor impurity concentration and the Fe concentration to obtain desired electrical characteristics of the claimed GaN crystal for forming a semiconductor device on top of the GaN crystal.
Regarding claim 3, Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. differ from the claimed invention by not having that a resistivity, measured between the top surface and a bottom surface of the GaN crystal, of not less than 5×108 Ω cm at 300oC.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the resistivity can be in the claimed range at the claimed temperature, because the resistivity of the GaN crystal should be controlled and optimized to obtain desired electrical characteristics at the operating temperatures of a semiconductor device formed on the GaN crystal.
Regarding claim 5, Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. differ from the claimed invention by not having a threading dislocation density on the top surface of less than 1×107 cm-2.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the threading dislocation density on the surface can be less than 1×107 cm-2, because (a) a semiconductor material having an ultralow threading dislocation density would allow forming a semiconductor device having excellent electrical characteristics due to less scattering and/or absorption of charge carriers, i.e. electrons and holes, by the threading dislocations, (b) the density of the threading dislocation can be controlled and optimized by controlling and optimizing the epitaxial growth conditions to improve quality of the GaN crystal, and (c) the claim is prima facie obvious without showing that the claimed range of the threading dislocation density achieves unexpected results relative to the prior art range. In re Woodruff, 16 USPQ2d 1935, 1937 (Fed. Cir. 1990). See also In re Huang, 40 USPQ2d 1685, 1688 (Fed. Cir. 1996) (claimed ranges of a result effective variable, which do not overlap the prior art ranges, are unpatentable unless they produce a new and unexpected result which is different in kind and not merely in degree from the results of the prior art). See also In re Boesch, 205 USPQ 215 (CCPA) (discovery of optimum value of result effective variable in known process is ordinarily within skill of art) and In re Aller, 105 USPQ 233 (CCPA 1955) (selection of optimum ranges within prior art general conditions is obvious).
Regarding claims 14 and 15, Vaudo et al. in view of Melnik et al. and further in view of Fujisawa et al. disclose a substrate, comprising the GaN crystal according to claim 1 (claim 14), wherein a GaN layer comprising the GaN crystal is laminated on a supporting substrate (sapphire substrate) (claim 15).
Claims 6 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Fujisawa et al. (US 2017/0327971)
Regarding claim 6, Fujisawa et al. disclose a GaN crystal having a top surface having an area of not less than 5 cm2 ([0103]), wherein the top surface has an inclination of not more than 10° with respect to the (0001) crystal plane ([0104]), and the GaN crystal has a (004) X-ray diffraction rocking curve full width at half maximum measured on the top surface of less than 30 arcsec and larger than 0 arcsec ([0045]-[0046], [0048]-[0049], [0051], [0053]-[0054], [0181], [0190]-[0191], [0193] and [0199]-[0200]).
Fujisawa et al. differ from the claimed invention by not showing that the GaN crystal is a semi-insulating crystal.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal can be a semi-insulating crystal, because (a) Applicants do not specifically claim the resistivity of the claimed semi-insulating GaN crystal, (b) therefore, when a GaN crystal is intrinsic or doped with acceptors with deep energy levels, which would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, the GaN crystal can be referred to as a semi-insulating GaN crystal, (c) a semi-insulating GaN crystal substrate has been commonly employed in manufacturing semiconductor devices such as GaN-based power devices since the semi-insulating GaN crystal substrate would allow one of ordinary skill in the art to manufacture GaN-based power devices without the semi-insulating GaN crystal substrate affecting the device operation very much, and (d) it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use, In re Leshin, 125 USPQ 416.
Regarding claim 20, Fujisawa et al. differ from the claimed invention by not showing that the GaN crystal has a threading dislocation density on the top surface of less than 1×1017 cm-2.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the threading dislocation density on the top surface can be less than 1×1017 cm-2, because (a) a semiconductor material having an ultralow threading dislocation density would allow forming a semiconductor device having excellent electrical characteristics due to less scattering and/or absorption of charge carriers, i.e. electrons and holes, by the threading dislocations, (b) the density of the threading dislocation can be controlled and optimized by controlling and optimizing the epitaxial growth conditions to improve quality of the GaN crystal, and (c) the claim is prima facie obvious without showing that the claimed range of the threading dislocation density achieves unexpected results relative to the prior art range. In re Woodruff, 16 USPQ2d 1835, 1837 (Fed. Cir. 1880). See also In re Huang, 40 USPQ2d 1685, 1688 (Fed. Chr. 1936) (claimed ranges of a result effective variable, which do not overlap the prior art ranges, are unpatentable unless they produce a new and unexpected result which is different in kind and not merely in degrees from the results of the prior art). See also In re Boesch, 208 USPQ 215 (COPA) (discovery of optimum value of result effective variable in known process is ordinarily within skill of arty and In re Aller, 105 USPQ 233 (COPA 1855) (selection of optimum ranges within prior art general conditions is obvious).
Claims 7, 11, 21 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Fujisawa et al. (US 2017/0327971) as applied to claim 6 above, and in view of Vaudo et al. (US 6,156,581) and further in view of Melnik et al. (US 6,936,357) The teachings of Fujisawa et al. are discussed above.
Regarding claim 7, 11, 21 and 22, Fujisawa et al. differ from the claimed invention by not having an Fe concentration of not less than 5×1017 atoms/cm3 and less than 1×1019 atoms/cm3, a total donor impurity concentration of at least one donor impurity selected from the group consisting of O, Si, S, Ge, and Sn of less than 5×1016 atoms/cm3, and a room-temperature resistivity of not less than 1×1011 Ω cm measured between the top surface and a bottom surface of the GaN crystal (claim 7), by not having an Fe concentration of not less than 5×1017 atoms/cm3 and less than 1×1019 atoms/cm3, a total donor impurity concentration of at least one donor impurity selected from the group consisting of O, Si, S, Ge, and Sn of less than 5×1016 atoms/cm3, and a resistivity measured between the top surface and a bottom surface of the GaN crystal, of not less than 5×108 Ω cm at 300oC (claim 11), the GaN crystal has a total concentration of at least one compensating impurity selected from the group consisting of Fe, C, Mn, Co, and Ni of not less than 5×1017 atoms/cm3 (claim 21), and the GaN crystal has a total donor impurity concentration of at least one donor impurity selected from the group consisting of O, Si, S, Ge, and Sn of less than 5×1016 atoms/cm3 (claim 22).
Vaudo et al. disclose a GaN crystal (col. 9, lines 13-17 and 29-31), wherein the GaN crystal has a total donor impurity concentration of donor impurities of O, Si, S, Ge, and/or Sn of less than 5×1016 atoms/cm2 (col. 12, lines 44-47 and 59-62).
Since both Fujisawa et al. and Vaudo et al. teach a GaN crystal, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal disclosed by Fujisawa et al. can further have the claimed total donor impurity concentration, because (a) the doping concentration of the GaN crystal disclosed by Fujisawa et al. should be controlled and optimized to obtain desired conductivity of the GaN crystal, and (b) the doping concentration of the GaN crystal should be determined based on applications of the GaN crystal.
Further regarding claims 7, 11 and 21, Fujisawa et al. in view of Vaudo et al. differ from the claimed invention by not having an Fe concentration of not less than 5×1017 atoms/cm3 and less than 1×1019 atoms/cm3, and a room-temperature resistivity of not less than 1×1011 Ω cm measured between the top surface and a bottom surface of the GaN crystal (claim 7), by not having an Fe concentration of not less than 5×1017 atoms/cm3 and less than 1×1019 atoms/cm3, and a resistivity measured between the top surface and a bottom surface of the GaN crystal, of not less than 1×1012 Ω cm at room temperature, not less than 5×1010 Ω cm at 100oC, not less than 2×109 Ω cm at 200oC, or not less than 5×108 Ω cm at 300oC (claim 11), and by not disclosing that the GaN crystal has a total concentration of at least one compensating impurity selected from the group consisting of Fe, C, Mn, Co, and Ni of not less than 5×1017 atoms/cm3.
Melnik et al. disclose a GaN crystal (Title) where “The inventors have found that in order to achieve the desired Na /Nd ratio and grow p-type GaN or AlGaN, the concentration of the acceptor impurity must be in the range of 1018 to 10 atoms per cubic centimeter, and more preferably in the range of 1019 to 1020 atoms per cubic centimeter”, and that “For an i-type layer, the doping level must be decreased, typically such that the dopant concentration does not exceed 1019 atoms per cubic centimeter” (col. 10, lines 2-10), where the p-type or i-type dopant can be Fe (col. 9, lines 12-19).
Since both Fujisawa et al./Vaudo et al. and Melnik et al. teach a GaN crystal, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal disclosed by Fujisawa et al./Vaudo et al. can be doped with Fe as disclosed by Melnik et al. with the Fe concentration in the GaN crystal as disclosed by Melnik et al., because (a) the GaN crystal disclosed by Vaudo et al. can be doped p-type or i-type to form a desired substrate or a buffer layer to in turn form a semiconductor device having desired electrical characteristics including an insulating or a semi-insulating substrate or buffer layer disclosed by Melnik et al., and (b) forming a semi-insulating GaN crystal employing Fe has been well-known in the semiconductor industry to form a semiconductor device on the insulating or semi-insulating GaN crystal substrate.
In this case, it would have been obvious, if not inherent, to one of ordinary skill in the art before the effective filing date of the claimed invention that a room-temperature resistivity is not less than 1×1011 Ω cm or not less than 1×1012 Ω cm, because (a) Fujisawa et al. in view of Vaudo et al. and further in view of Melnik et al. disclose all the claim limitations of claims 7 and 11, and therefore, if Fujisawa et al. in view of Vaudo et al. in view of Melnik et al. do not disclose the claimed room-temperature resistivity, claims 7 and 11 would be further indefinite for not claiming an essential and critical feature to the practice of the claimed invention, and (c) if arguendo Fujisawa et al. in view of Vaudo et al. and further in view of Melnik et al. do not disclose the claimed room-temperature resistivity, then it would at least have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the GaN crystal disclosed by Fujisawa et al. in view of Vaudo et al. and further in view of Melnik et al. can have the claimed room-temperature resistivity by controlling the total donor impurity concentration and the Fe concentration to obtain desired electrical characteristics of the claimed GaN crystal for forming a semiconductor device on top of the GaN crystal.
Response to Amendment
The Declaration under 37 CFR 1.132 filed November 21, 2025 is insufficient to overcome the rejection of claims 1 and 6 based upon Vaudo et al. (US 6,156,581) in view of Melnik et al. (US 6,936,357) and further in view of Fujisawa et al. (US 2017/0327971) or Fujisawa et al. (US 2017/0327971) as set forth in the last Office action because: (a) Applicants’ arguments are based on attacking the teachings of the individual references, and in response to Applicants' arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references, see In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), (b) in addition, it appears that Applicants misunderstood the prior art rejection included in the Non Final Office Action mailed July 21, 2025, which was made under 35 USC 103 rather than 35 USC 102, and (c) in other words, while the prior art reference of Fujisawa et al. was used to show that a (004) X-ray diffraction rocking curve full width half maximum can be reduced by the method disclosed by Fujisawa et al., Applicants simply argue that the claimed range of the (004) X-ray diffraction rocking curve full width half maximum may not be achieved, which appears to be arguments traversing a 35 USC 102 rejection rather than a 35 USC 103 rejection.
Response to Arguments
Applicants’ arguments with respect to claims 1 and 6 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Applicants’ arguments traversing the 35 USC 112(a) rejection on pages 8-10 of the REMARKS filed November 21, 2025 are not persuasive, especially because Applicants added a new matter as discussed above under 35 USC 112(a) rejections.
Applicants’ arguments traversing the 35 USC 103 rejection on pages 20 of the REMARKS are not persuasive, because (a) as discussed above, Applicants’ arguments are primarily based on attacking the teachings of the individual references, and in response to Applicants' arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references, see In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), (b) in addition, it appears that Applicants misunderstood the prior art rejection included in the Non Final Office Action mailed July 21, 2025, which was made under 35 USC 103 rather than 35 USC 102, and (c) in other words, while the prior art reference of Fujisawa et al. was used to show that a (004) X-ray diffraction rocking curve full width half maximum can be reduced by the method disclosed by Fujisawa et al., Applicants simply argue that the claimed range of the (004) X-ray diffraction rocking curve full width half maximum may not be achieved, which appears to be arguments traversing a 35 USC 102 rejection rather than a 35 USC 103 rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Fujikura et al. (US 11,339,053)
Kotani et al. (US 9,548,365)
Applicants' amendment necessitated the new grounds of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicants are 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 JAY C KIM whose telephone number is (571) 270-1620. The examiner can normally be reached 8:00 AM - 6:00 PM EST.
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/JAY C KIM/Primary Examiner, Art Unit 2815
/J. K./Primary Examiner, Art Unit 2815 January 27, 2026