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 § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
The term “reducing oxidation” and “reducing electrical activity of defects” in claims 25, 26, and 38 is a relative term which renders the claim indefinite. The term “reducing” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
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.
Claims 25-44 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Dimitrijev et al (U.S. Pub #2012/0056194).
With respect to claim 25, Dimitrijev teaches a method for reducing the electrical activity of defects (Paragraph 4, 32, and 34, reduction of stacking faults) in a silicon carbide epitaxial layer (Fig. 1A, 176) grown on a silicon wafer (Fig. 1A, 172), the method comprising
reducing oxidation of silicon during growth of the silicon carbide epitaxial layer (Paragraph 4 and 26).
With respect to claim 26, Dimitrijev teaches a method for manufacturing a silicon carbide epitaxial layer, the method comprising:
providing a silicon wafer (Fig. 1A, 172);
growing a silicon carbide epitaxial layer (Fig. 1A, 176)on the silicon wafer; and
reducing oxidation of silicon during growth of the silicon carbide epitaxial layer (Paragraph 4 and 26).
With respect to claim 27, Dimitrijev teaches that reducing oxidation of silicon comprises: introducing a precursor during epitaxial growth of the silicon carbide epitaxial layer (Fig. 6); and
configuring the precursor such that oxygen reacts preferentially with the precursor over the silicon.
In reference to the claim language referring to the function of the precursor, intended use and other types of functional language must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. In a claim drawn to a process of making, the intended use must result in a manipulative difference as compared to the prior art. In re Casey,152 USPQ 235 (CCPA 1967); In re Otto , 136 USPQ 458, 459 (CCPA 1963). MPEP 2114
With respect to claim 28, Dimitrijev teaches that the precursor comprises any of: aluminum (Paragraph 46, TMAl); titanium; magnesium; and/or calcium.
With respect to claim 29, Dimitrijev teaches that the precursor forms an energy state in the bandgap of the silicon carbide (e.g. the bandgap is modified by doping).
With respect to claim 30, Dimitrijev teaches introducing an n-type dopant (Fig. 1A, 152) during growth of the silicon carbide epitaxial layer.
With respect to claim 31, Dimitrijev teaches introducing the n-type dopant at the same time as introducing the precursor (Fig. 4, 464; Fig. 6, 664).
With respect to claim 32, Dimitrijev teaches that the n-type dopant is nitrogen (Paragraph 29).
With respect to claim 33, Dimitrijev teaches introducing the precursor at a level suitable to result in a doping concentration of the silicon carbide by the precursor of less than E17 per cubic centimetre (Paragraph 46).
With respect to claim 34, Dimitrijev teaches introducing the precursor at a level suitable to result in a doping concentration of the silicon carbide by the precursor of less than E16 per cubic centimetre (Paragraph 46).
With respect to claim 35, Dimitrijev teaches that the growth of the silicon carbide epitaxial layer comprises reacting gases; and wherein the method further comprises using a scavenger plate or tube to remove oxygen from the gases prior to reacting the gases (Paragraph 32).
With respect to claim 36, Dimitrijev teaches that the silicon carbide epitaxial layer comprises 3-step cubic silicon carbide (3c SiC) (Paragraph 31).
With respect to claim 37, Dimitrijev teaches that the defects comprise stacking faults (Paragraph 34), and/or microtwins.
With respect to claim 38, Dimitrijev teaches a semiconductor structure comprising:
a silicon wafer (Fig. 1A, 172); and
a silicon carbide epitaxial layer (Fig. 1A, 176) grown on the silicon wafer;
wherein the silicon carbide epitaxial layer is doped with a precursor (Fig. 6 and Paragraph 46), the precursor being configured to reduce oxidation of silicon during growth of the silicon carbide epitaxial layer.
In reference to the claim language referring to the function of the precursor, intended use and other types of functional language must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. In a claim drawn to a process of making, the intended use must result in a manipulative difference as compared to the prior art. In re Casey,152 USPQ 235 (CCPA 1967); In re Otto , 136 USPQ 458, 459 (CCPA 1963). MPEP 2114
With respect to claim 39, Dimitrijev teaches that the silicon carbide layer is n-type (Fig. 1A, 176 and 152).
With respect to claim 40, Dimitrijev teaches that the silicon carbide layer is nitrogen-doped (Paragraph 29).
With respect to claim 41, Dimitrijev teaches that a doping concentration of the precursor in the silicon carbide epitaxial layer is less than E17 per cubic centimetre or less than E16 per cubic centimetre (Paragraph 46).
With respect to claim 42, Dimitrijev teaches that the silicon carbide epitaxial layer comprises 3-step cubic silicon carbide (3c SiC) (Paragraph 31).
With respect to claim 43, Dimitrijev teaches that the precursor comprises any of: aluminum (Paragraph 46, TMAl); titanium; magnesium; and/or calcium.
With respect to claim 44, Dimitrijev teaches a semiconductor device (Paragraph 28, etc.) comprising the semiconductor structure of claim 38.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BENJAMIN P SANDVIK whose telephone number is (571)272-8446. The examiner can normally be reached M-F: 10-6.
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/BENJAMIN P SANDVIK/Primary Examiner, Art Unit 2812
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