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
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1,3 & 17 is/are rejected under 35 U.S.C. 102(a)(1)as being anticipated by Furukawa (JPH02253622 A) as cited in IDS.
Regarding claim 1, Furukawa et al discloses A method for producing a silicon carbide substrate(2), wherein the method comprises: providing the silicon carbide substrate(2) and irradiating the silicon carbide substrate (2)(pp. 6 lines 27-28)with particles out of a group comprising boron atoms(line 8 pp 6), wherein an energy of the particles for irradiation is selected such that a resistivity (p) is increased by the irradiation at least in a part (4)of the silicon carbide substrate and the silicon carbide substrate(2) is semiconducting with a resistivity in a range between 10² Ω cm and 10⁵ Ω cm after irradiation(pp. 7 lines 1-14).
Regarding claim 3, Furukawa et al discloses wherein the resistivity (p) is
increased up to a range between 10² Ω cm and 10⁵ Ω cm by the irradiation(pp. 7 lines 13-14).
Regarding claim 8, Furukawa et al discloses wherein providing the silicon
carbide substrate(2) as a silicon carbide wafer having a first main side and a second main side, wherein during irradiating the silicon carbide substrate(2), the particles enter the first main side of the silicon carbide wafer(2) fig. 1d.
Regarding claim 17, Furukawa et al discloses wherein the method comprises annealing the silicon carbide substrate after irradiation(lines 14-16 pp. 7).
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.
Claim(s) 1,3, 4-5, 8-11, 16, 18, 19, & 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kaneko (WO 2012/053081 A1).
Regarding claim 1, Kaneko et al discloses A method for producing a silicon carbide substrate(3), wherein the method comprises: providing the silicon carbide substrate(3) and irradiating the silicon carbide substrate (3)with particles out of a group comprising electrons(pp. 5 Embodiment 1), wherein an energy of the particles for irradiation is selected such that a resistivity (̬ρ) is increased by the irradiation at least in a part(6) of the silicon carbide substrate(3) and the silicon carbide substrate(3) is semiconducting after irradiation(pp. 6 para 1).
Kaneko et al discloses wherein the resistivity (p) is in a range(pp. 4, para 3) but fails to teach between 102 Ω cm and 10⁵ Ω cm by the irradiation. Kaneko et al teaches a generation density of electron capture centers is directly proportional to electron beam fluence and is governed by the magnitude of the electron beam energy(see para 2 pp. 13 and 14 and fig 4 and fig. 5). Kaneko et al explicitly identifies electron energy and fluence as result effective variables that dictate trap density and resistivity. Fig. 4 and fig. 5 shows how to tune these parameters to achieve an arbitrary resistivity(see fig. 5 a resistivity value of approximately 104Ω cm that can be interpolated from the graph at specific energies of 400 keV and 580 KeV). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to adjust the fluence and energy to achieve between 102 and 105 Ω cm through routine experimentation. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). A variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977).
Regarding claim 3, Kaneko et al discloses wherein the resistivity (p) is up to a range(pp. 4, para 3) but fails to teach between 102 Ω cm and 10⁵ Ω cm by the irradiation. Kaneko et al teaches a generation density of electron capture centers is directly proportional to electron beam fluence and is governed by the magnitude of the electron beam energy(see para 2 pp. 13 and 14 and fig 4 and fig. 5). Kaneko et al explicitly identifies electron energy and fluence as result effective variables that dictate trap density and resistivity. Fig. 4 and fig. 5 shows how to tune these parameters to achieve an arbitrary resistivity(see fig. 5 a resistivity value of approximately 104Ω cm that can be interpolated from the graph at specific energies of 400 keV and 580 KeV). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to adjust the fluence and energy to achieve between 102 and 105 Ω cm through routine experimentation. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). A variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977).
Regarding claim 4, Kaneko et al discloses wherein before irradiating
the silicon carbide substrate(3), the silicon carbide substrate(3) is a conducting silicon
carbide substrate with a resistivity of equal or lower than 10-2 Ω cm(fig. 5).
Regarding claim 5, wherein the entirety of the silicon carbide substrate (3)has an n-type conductivity before and after irradiation(fig. 5, pp 13 para 1).
Regarding claim 8, Kaneko et al discloses wherein providing the silicon carbide substrate (3)as a silicon carbide wafer having a first main side and a second main side, wherein during irradiating the silicon carbide substrate(3), the particles enter the first main side of the silicon carbide wafer(fig. 1/fig. 2).
Regarding claim 9, Kaneko et al discloses wherein irradiating with electrons as
the particles with at least one of an energy (para 2 pp. 6) but fails to teach in a range
between 140 keV and 180 keV. Kaneko et al teaches a generation density of electron capture centers is directly proportional to electron beam fluence and is governed by the magnitude of the electron beam energy(see para 2 pp. 13 and 14 and fig 4 and fig. 5). Substrate thickness and penetration depth directly correlates to beam energy. Kaneko et al teaches that beam energy and irradiation dose influence depth and resistivity (pp. 6 para 2). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to achieve energy range between 140 keV and 180 keV through routine experimentation to optimize resistivity. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). A variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977).
Regarding claim 10, Kaneko et al discloses wherein the particles for irradiation
are electrons having an energy in a range and a thickness of the silicon carbide wafer (3) (para 2 pp. 6) but fails to teach energy in a range between 450 keV and 550 keV and thickness range between 315 µm to 385 µm. Kaneko et al teaches a generation density of electron capture centers is directly proportional to electron beam fluence and is governed by the magnitude of the electron beam energy(see para 2 pp. 13 and 14 and fig 4 and fig. 5). Kaneko et al explicitly identifies electron energy and fluence as result effective variables that dictate depth and resistivity (pp. 6 para 2). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to achieve energy in a range between 450 keV and 550 keV and thickness range between 315 µm to 385 µm through routine experimentation to optimize resistivity. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955)
Regarding claim 11, Kaneko et al discloses wherein irradiating with electrons as the particles with a dose between 0.5.10¹⁰ cm⁻² and 2.10¹⁹ cm⁻²(pp. 9 para 4).
Regarding claim 16, Kaneko et al discloses wherein the silicon carbide substrate(6/3) is free from a silicon carbide epitaxial layer fig. 1/fig. 2 (para 3 pp 6).
Regarding claim 18, Kaneko et al discloses wherein the silicon carbide substrate (3/6)is not attached to a carrier wafer before and during irradiation fig. 1(para 3 pp. 6) .
Regarding claim 19, Kaneko et al discloses wherein the energy of the particles(1) for irradiation is selected such that at least a part of the particles pass through the silicon carbide substrate(3)(fig. 2).
Regarding claim 20, Kaneko et al discloses wherein the silicon carbide substrate (6/3)is configured for fabrication of a power semiconductor device(pp8 para 3).
Allowable Subject Matter
Claims 2, 6, 7, 12, 13, 14, & 15 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Response to Arguments
Applicant's arguments filed 5/1/ 2026 have been fully considered but they are not persuasive. Applicant argues Kaneko discloses a method for manufacturing a semi-insulating SiC crystal having a resistivity of 1 X 10+5 Ω-cm or greater. Kaneko's method is expressly directed to producing semi-insulating SiC crystals with resistivity at or above 10⁵ Ω cm, which is the upper boundary of the claimed semiconducting range. Kaneko does not disclose or teach producing a silicon carbide substrate that is semiconducting with a resistivity in the range between 10² Ω cm and 10⁵ Ω cm. The parameters are not result-effective variables that would be optimized to achieve Kaneko's objective.
Regarding claim 9, the claimed electron energy "in a range between 140 keV and
V" is not a result-effective variable that Kaneko teaches optimizing. Kaneko teaches that realistic electron beam energy is preferably 200 keV or more, and more preferably 400 keV or more. The claimed energy range of 140-180 keV is below Kaneko's preferred range and is specifically selected to achieve a semiconducting substrate with resistivity in the range of 10² to 10⁵ Ω cm, not the semi-insulating properties that Kaneko seeks.
Regarding claim 10, the claimed electron energy "in a range between 450 keV and 550 keV" and thickness "in a range between 315 µm to 385 µm" are parameters selected to achieve a semiconducting substrate, not the semi-insulating substrate that Kaneko teaches.
Examiner notes, with regards to limitation of claim 3, with a resistivity in the range between 10² Ω cm and 10⁵ Ω cm, Kaneko et al discloses a controllable process for tailoring resistivity. The reference teaches that the generation density of electron capture centers is directly proportional to electron beam fluence and is governed by the magnitude of the electron beam energy. Kaneko et al discloses a functional relationship and a proportional coefficient between these variables allowing one of ordinary skill in the art to determine the resistivity realized with an arbitrary energy and fluence (see para 2 pp. 13 and 14 and fig 4 and fig. 5). Kaneko et al explicitly identifies electron energy and fluence as result effective variables that dictate trap density and resistivity. Fig. 4 and fig. 5 shows how to tune these parameters to achieve an arbitrary resistivity. Therefore, a person of ordinary skill in the art, would be able to adjust the fluence and energy to achieve between 102 and 105 Ω cm through routine experimentation. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990)
With regards to claim 9, Kaneko et al discloses when the energy of electron beam is 80 keV or more, generation of an electron capture center that becomes the basis for development of high resistance starts (Table 1 fig 4). The generation rate of the electron capture center increases as the energy of the electron beam increases (para 1 pp. 10). Therefore , the claimed range of 140 KeV to 180 KeV falls within Kaneko et al operable range. The fact that Kaneko et al expresses preference for higher energy levels does not teach away from lower values provided by the reference. Furthermore, Kaneko et al discloses that electron energy and fluence are result effective variables. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to select a range of 140 KeV to 180 KeV through routine experimentation to adjust trap density and resistance. [W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) .A variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977).
With regards to claim 10, with regards to applicant’s argument that the claimed energy range of 400 keV to 550 keV and the thickness range of 315 micrometers to 385 micrometers are parameters chosen to achieve a semiconducting substrate rather than Kaneko’s semi-insulating substrate is unpersuasive. Examiner notes, Kaneko teaches that the electron beam energy and fluence are result effective variables that dictate trap density and resistivity. Kaneko et al disclosure encompasses energy levels up to and exceeding this range (operational examples of 400 keV and 580 keV)para 2 pp. 13-14. Substrate thickness and penetration depth directly correlates to beam energy. Kaneko et al teaches at 400 KeV that 230 micrometers can be achieved and that beam energy and irradiation dose influence depth and resistivity (pp. 6 para 2). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to adjust beam energy to a range of 400 keV to 550 keV to achieve a thickness range of 315 micrometers to 385 micrometers through routine experimentation. [W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) .A variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977). Although Kaneko specifically characterizes its resulting substrate as semi insulating , Fig. 5 shows a resistivity value of approximately 104Ω cm that can be interpolated from the graph at specific energies of 400 keV and 580 KeV, falling withing the semiconductive range of between 10² Ω cm and 10⁵ Ω cm as claimed. Therefore, the claimed range of 400 keV to 550 keV and a thickness range of 315 micrometers to 385 micrometers can be achieved through routine experimentation.
Applicant's submission of an information disclosure statement under 37 CFR 1.97(c) with the timing fee set forth in 37 CFR 1.17(p) on 5/1/2026 prompted the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 609.04(b). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LATANYA N CRAWFORD EASON whose telephone number is (571)270-3208. The examiner can normally be reached Monday-Friday 8:30 AM-4:30 PM.
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/LATANYA N CRAWFORD EASON/ Primary Examiner, Art Unit 2813
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