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 .
Election/Restrictions
Per applicant’s response to election/restriction filed on 05/20/2026, the applicant elects invention II, claims 16-20 without traverse. Claims 16-30 are examined upon the merits below.
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) 16-21 and 23 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Shimizu et al (US 20190296146).
Shimizu et al teaches
[claim 16] A semiconductor device, comprising: a silicon carbide layer having a surface inclined by an angle equal to or more than 0 degrees and equal to or less than 8 degrees with respect to a {0001} face and including a trench (figure 13, paragraph 0028, where element 10 is a silicon carbide layer having a surface inclined by an angle equal to or more than 0 degrees and equal to or less than 8 degrees with respect to a face [in the present case it is shown at 0 degrees] and includes a trench [elements 60, 40, 28 and 30 fill in the trench in element 10]);
a gate electrode provided in the trench (figure 13, paragraph 0028, where element 30 is the gate electrode provided in the trench),
a silicon oxide layer provided between the silicon carbide layer and the gate electrode (figure 13, paragraph 0028, where element 28 [gate insulating layer] is the silicon oxide layer between the gate electrode [element 30] and the silicon carbide layer [element 10]),
and a region provided between the silicon carbide layer and the silicon oxide layer and containing nitrogen (N) and at least one element selected from a group consisting of hydrogen (H), deuterium (D), and fluorine (F) (figure 13, paragraphs 0026-0028, elements 60 and 40 [labeled first and second regions] comprise the region between the silicon carbide layer [element 10] and the silicon oxide layer [element 28] and contains nitrogen as well as hydrogen, deuterium or fluorine).
[claim 17] The semiconductor device according to claim 16, wherein an atomic concentration of the at least one element in the region is lower than an atomic concentration of nitrogen in the region (figures 4 and 13, paragraphs 0026 and 0063-0066, where the “termination region” and “nitrogen region” comprise the region, per figure 4 there is a nitrogen concentration within the nitrogen region [part of the region] higher than the termination element concentration [which is the concentration of one of the elements hydrogen, deuterium, or fluorine]).
[claim 18] The semiconductor device according to claim 16, wherein a concentration distribution of nitrogen in the silicon carbide layer, the silicon oxide layer, and the region has a peak in the region (figures 4 and 13, paragraphs 0026 and 0064, where the peak nitrogen concentration in the gate insulating layer [silicon oxide] and silicon carbide layer is located in the region [where “nitrogen region” is one part of the region]).
[claim 19] The semiconductor device according to claim 18, wherein an atomic concentration of nitrogen at the peak is equal to or more than 1 × 1021 cm-3 (figures 4 and 13, paragraph 0064, where the peak nitrogen concentration can be upwards of 1 × 1022 cm-3 – which is greater than 1 × 1021 cm-3).
[claim 20] The semiconductor device according to claim 16, wherein a concentration distribution of the at least one element in the silicon carbide layer, the silicon oxide layer, and the region has a peak in the region (figures 4 and 13, paragraphs 0026 and 0065-0066, where the “termination element” is the element of layer 40 which is one of the hydrogen, deuterium, and fluorine, and has a peak concentration in the region [which comprises both the “termination region [[element 40]] and the nitrogen region [[element 60]]).
[claim 21] The semiconductor device according to claim 20, wherein an atomic concentration of the at least one element at the peak is equal to or more than 1 × 1017 cm-3 (figures 4 and 13, paragraphs 0065-0066, where the peak concentration of the at least one element [called “termination element”] is upwards of 1 × 1023 cm-3 which is more than 1 × 1017 cm-3).
Regarding claim 23,
[claim 23] The semiconductor device according to claim 16, wherein a threshold voltage fluctuation when AC stress of 1MHz from -5 MV/cm to 5 MV/cm is applied for 100 hours between the silicon carbide layer and the gate electrode is less than 0.1 V.
Per MPEP 2114 Apparatus and Article Claims — Functional Language [R-07.2015]
For a discussion of case law which provides guidance in interpreting the functional portion of means-plus-function limitations see MPEP § 2181 - § 2186.
II. MANNER OF OPERATING THE DEVICE DOES NOT DIFFERENTIATE APPARATUS CLAIM FROM THE PRIOR ART
"[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (emphasis in original). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987) (The preamble of claim 1 recited that the apparatus was "for mixing flowing developer material" and the body of the claim recited "means for mixing ..., said mixing means being stationary and completely submerged in the developer material." The claim was rejected over a reference which taught all the structural limitations of the claim for the intended use of mixing flowing developer. However, the mixer was only partially submerged in the developer material. The Board held that the amount of submersion is immaterial to the structure of the mixer and thus the claim was properly rejected.).
In the present case only the structure which is claimed is examined. With regards to claim 23, there is no extra structural limitation claimed in claim 23, thus the structure of claim 16 [the parent claim] is the only examined structural limitation of claim 23, which is rejected above, because all the structure and material items are present, Shimizu et al., is ‘configured” such that when AC stress of 1MHz from -5 MV/cm to 5 MV/cm is applied for 100 hours between the silicon carbide layer and the gate electrode, a threshold voltage fluctuation is less than 0.1 V.
Claim(s) 24-25, and 28 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ohashi et al (US 20160247884).
Ohashi et al teaches,
[claim 24] A semiconductor device, comprising: a silicon carbide layer (figure 14, paragraph 0027, where elements 12-20 [vertical stack] is the silicon carbide layer),
a gate electrode containing polycrystalline silicon containing boron (B) (figure 14, paragraph 0039, where element 30 is the gate electrode and contains polycrystalline silicon with boron);
a silicon oxide layer provided between the silicon carbide layer and the gate electrode (figure 13, paragraph 0027, where element 28 is the gate insulating layer [which is made of silicon oxide and is the silicon oxide layer]);
a first region provided between the silicon carbide layer and the silicon oxide layer and containing nitrogen (N) (figure 14, paragraph 0041, where the first region [element 40 is situated between the silicon carbide layer [element 12] and the silicon oxide layer [element 28]);
and a second region provided between the silicon oxide layer and the gate electrode and containing nitrogen (N) (figure 14, paragraph 0047, where element 60 is the second region provided between the silicon oxide layer [element 28] and the gate electrode [element 30] and contains nitrogen).
[claim 25] The semiconductor device according to claim 24, wherein the silicon carbide layer includes a trench, a surface of the silicon carbide layer is inclined by an angle equal to or more than 0 degrees and equal to or less than 8 degrees with respect to a {0001} face, and the gate electrode is provided in the trench (figure 13, paragraph 0026-0028, where elements 12-20 [vertical stack] is the silicon carbide layer and has a trench formed in it, where the trench is filled in by the gate electrode [element 30, as well as elements 40, 28 and 60], and has an incline greater than or equal to 0 degrees).
[claim 28] The semiconductor device according to claim 24, wherein the first region contains at least one element selected from a group consisting of hydrogen (H), deuterium (D), and fluorine (F), and the second region contains at least one element selected from the group consisting of hydrogen (H), deuterium (D), and fluorine (F) (figure 12, paragraph 0077, where the first and second regions contain fluorine).
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) 22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shimizu et al (US 20190296146) in view of Ohashi et al (US 20160247907).
Shimizu et al teaches all of the limitations of the parent claim, claim 16, but does not specifically disclose,
[claim 22] The semiconductor device according to claim 16, wherein, in the region, an amount of the at least one element bonded to carbon (C) is larger than an amount of the at least one element bonded to silicon (Si).
However, Ohashi et al does teach
[claim 22] The semiconductor device according to claim 16, wherein, in the region, an amount of the at least one element bonded to carbon (C) is larger than an amount of the at least one element bonded to silicon (Si) (paragraphs 0071-0072, and 0082, where deuterium [one of the at least one elements] is bonded to carbon in the region [element 40] and has a specific peak concentration bonded to carbon, but is not bonded to silicon in said region, thus the amount of the at least one element bonded to carbon is greater than said element bonded to silicon).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the present application to have modified the teachings of Shimizu et al to incorporate the teachings of Ohashi et al in order to terminate the carbon bonds with deuterium instead of using a silicon bonded termination region to form a more stable bond and lowering oxide leakage, thus lowering oxidization of the electrode making a more efficient device overall.
Claim(s) 26, 27, 29 and 30 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ohashi et al (US 20160247884) in view of Shimizu et al (US 20160284804).
Ohashi et al teaches all of the limitations of the parent claim, claim 24, and further dislcoses
[claim 26] The semiconductor device according to claim 24, wherein a concentration distribution of nitrogen in the silicon carbide layer, the first region, the silicon oxide layer, the second region, and the gate electrode has a first peak in the first region (figure 14, paragraphs 0042-0043, where a concentration distribution of Nitrogen in the silicon carbide layer, first region, silicon oxide layer, second region and gate electrode has a peak in the first region).
[claim 29] The semiconductor device according to claim 28, wherein a concentration distribution of nitrogen in the silicon carbide layer, the first region, the silicon oxide layer, the second region, and the gate electrode has a first peak in the first region (figure 14, paragraphs 0042-0043, where a concentration distribution of Nitrogen in the silicon carbide layer, first region, silicon oxide layer, second region and gate electrode has a peak in the first region),
and a concentration distribution of the at least one element in the silicon carbide layer, the first region, the silicon oxide layer, the second region, and the gate electrode has a third peak in the first region and a fourth peak in the second region (figures 12 and 14, paragraphs 0042-0044 and 0047-0048, where the first region has a third peak concentration of fluorine and the second region has a fourth peak concentration of fluorine as shown by the graphs in figure 12).
[claim 30] The semiconductor device according to claim 29, wherein an atomic concentration of nitrogen at the first peak is equal to or more than 1 × 1021 cm-3, and an atomic concentration of the at least one element at the third peak and an atomic concentration of the at least one element at the fourth peak is equal to or more than 1 × 1017 cm-3 (paragraph 0043, where nitrogen has a peak concentration greater than 1 × 1020 cm-3 which is greater than 1 × 1021 cm-3, and the atomic concentration of fluorine [the at least one of the element] has a third peak concentration greater than 1 × 1017 cm-3 as shown by the graph in figure 12 where the peak concentration is upwards of 1 × 1019 cm-3, and a fourth peak in the second region has a peak concentration greater than 1 × 1017 cm-3 as shown by figure 12, where the peak concentration is upwards of 1 × 1018 cm-3).
However, Ohashi et al does not specifically disclose
[claim 26] and a second peak in the second region.
[claim 27] The semiconductor device according to claim 26, wherein an atomic concentration of nitrogen at the first peak and an atomic concentration of nitrogen at the second peak are equal to or more than 1 × 1021 cm-3.
[claim 29] and a second peak in the second region,
[claim 30] an atomic concentration of nitrogen at the second peak are equal to or more than 1 × 1021 cm-3.
However, Shimizu et al does teach,
[claim 26] and a second peak in the second region (figure 9B, paragraph 0105, where a second peak concentration has a peak of Nitrogen in a second region).
[claim 29] and a second peak in the second region (figure 9B, paragraph 0105, where a second peak concentration has a peak of Nitrogen in a second region).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the present application to have modified the teachings of Ohashi et al with the teachings of Shimizu et al in order to have a second layer of nitrogen concentration in the second region to maximize the dielectric properties of the gate insulating layer [i.e. by stopping boron diffusion from gate to silicon carbide layer] thus improving overall efficiency of the device.
Additionally, regarding claims 27 and 30,
Per MPEP 2144.05 Obviousness of Similar and Overlapping Ranges, Amounts, and Proportions [R-01.2024]
See MPEP § 2131.03 for case law pertaining to rejections based on the anticipation of ranges under 35 U.S.C. 102 and 35 U.S.C. 102 /103.
II. ROUTINE OPTIMIZATION
A. Optimization Within Prior Art Conditions or Through Routine Experimentation
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[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) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages."); In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969) (Claimed elastomeric polyurethanes which fell within the broad scope of the references were held to be unpatentable thereover because, among other reasons, there was no evidence of the criticality of the claimed ranges of molecular weight or molar proportions.). For more recent cases applying this principle, see Merck & Co. Inc. v. Biocraft Lab. Inc., 874 F.2d 804, 809, 10 USPQ2d 1843, 1848 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989)(Claimed ratios were obvious as being reached by routine procedures and producing predictable results); In re Kulling, 897 F.2d 1147, 1149, 14 USPQ2d 1056, 1058 (Fed. Cir. 1990)(Claimed amount of wash solution was found to be unpatentable as a matter of routine optimization in the pertinent art, further supported by the prior art disclosure of the need to avoid undue amounts of wash solution); and In re Geisler, 116 F.3d 1465, 1470, 43 USPQ2d 1362, 1366 (Fed. Cir. 1997)(Claims were unpatentable because appellants failed to submit evidence of criticality to demonstrate that that the wear resistance of the protective layer in the claimed thickness range of 50-100 Angstroms was "unexpectedly good"); Smith v. Nichols, 88 U.S. 112, 118-19 (1874) (a change in form, proportions, or degree "will not sustain a patent"); In re Williams, 36 F.2d 436, 438, 4 USPQ 237 (CCPA 1929) ("It is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions."). See also KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416, 82 USPQ2d 1385, 1395 (2007) (identifying "the need for caution in granting a patent based on the combination of elements found in the prior art.").
It would have been obvious to one of ordinary skill in the art before the effective filing date of the present application to have modified the teachings of Ohashi et al as modified to incorporate different ranges into the second peak nitrogen layer, specifically to be above 1 × 1021 cm-3 in order to maximize the dielectric properties of the layers between the gate insulating layer [silicon oxide] and the gate electrode to allow greatest efficiency of said device through routine experimentation for the specific use case.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Tanaka (US 20220231142), Sakai et al (US 20220123141), Shimizu et al (US 20220005925), Shimizu et al (US 20210296128), Shimizu (US 20200091297), Uchida et al (US 20190198622), Iijima et al (US 20190198619), Shimizu et al (US 10211301), Shimizu et al (US 20170104072) as other devices with modified gate insulating layers with specific concentrations of various elements (such as Nitrogen plus other elements) to maximize the dielectric effect of the insulating layer.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW ZABEL whose telephone number is (703)756-4788. The examiner can normally be reached M-F 9-5PM ET.
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/ANDREW JOHN ZABEL/Examiner, Art Unit 2818
/JEFF W NATALINI/Supervisory Patent Examiner, Art Unit 2818
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