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 .
Election/Restrictions
Applicant’s election without traverse of Species III with claims 1-11 and 15-21 indicated by Applicant to read thereon, in the reply filed on 10/21/2025 is acknowledged.
While Examiner acknowledges that Applicant indicated that claims 19-21 read on the elected species III, claims 19-21 does not read on the elected species because it at least fails to show the floating pockets are spaced apart from each other by a protection distance that is less than the body distance and are hereby withdrawn from further consideration therefor.
Claims 19-21 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10/21/2025.
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.
Claims 7-8 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Re claim 7, line 4, the phrase “the epitaxial layer” is unclear and indefinite (which one? e.g., the first and/or second and/or intermediate epitaxial layer?).
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 4, 6 and 15-18 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Chi et al., US Pub. No. 2021/0391416 A1.
Re claim 1. Chi et al. disclose a semiconductor power device, comprising: a first conduction terminal 111 (e.g., fig. 4) and a second conduction terminal 112 (e.g., fig. 4); a semiconductor body 101/102 containing silicon carbide and having a first conductivity type (n-type, e.g. fig. 4); body wells 103 having a second conductivity type (e.g., p-type, fig. 4) in the semiconductor body and separated from one another by a body distance (e.g. in horizontal direction, fig. 4); source regions 104 in the body wells 103 (e.g., fig. 4); an enrichment layer 105 (e.g., and/or an upper portion of 104, fig. 4); and floating pockets 106 (e.g., or 107, fig. 4) having the second conductivity type (e.g., p-type, fig. 4), in the semiconductor body at a distance (fig. 4, or at least the vertical far end of 107 and/or the portion not in contact w/ 103) from the body wells 103 between a first face (e.g., the top surface of 102) and a second face (e.g., the bottom surface of 101) of the semiconductor body 101/102 (e.g., fig. 4), the enrichment layer 105 (e.g., and/or an upper portion of 104, fig. 4) being between the first face (e.g., the top surface of 102) and the body wells 103 (e.g, fig. 4), see figs. 1-13 and pages 1-9 for more details.
Re claim 4. The device according to claim 1 wherein the floating pockets 106 are spaced from each other by a protection distance that is greater than the body distance (e.g., the horizontal direction, fig. 4).
Re claim 6. The device according to claim 4 wherein a protection-to-body distance between the floating pockets 107 (e.g., the portion other than the contacting portion, fig. 4) and the corresponding body wells 103 (fig. 4) in a direction transverse (e.g., vertically, fig. 4) to the first face and to the second face of the semiconductor body is less than the body distance (e.g., fig. 4).
Re claim 15. Chi et al. disclose a device, comprising: a substrate 102 (e.g., a lower portion of 102) having a first conductivity type (e.g, n-type, fig. 4); a first and second floating pocket 106 in the substrate and having a second conductivity type (e.g., p-type, fig. 4); a first layer 102 (an upper portion of 102, e.g., the portion above element 106) on the substrate (fig. 4), the first layer having the first conductivity type (e.g, n-type, fig. 4); a first and second body well 103 (e.g., fig. 4) in the first layer, the first and second body well 103 having the second conductivity type (e.g., p-type), the first and second body well 103 being spaced from the first and second floating pockets 106 by a first distance in a first direction (e.g., vertical direction, fig. 4), the first body well 103 being spaced from the second body well 103 by a second distance in a second direction (e.g., horizontal direction, fig. 4) that is transverse to the first direction (e.g., fig. 4), the first floating pocket 106 being spaced from the second floating pocket 106 by a third distance in the second direction (e.g., horizontal direction, fig. 4), the third distance being greater than the second distance (e.g., fig. 4). See figs. 1-13 and pages 1-9 for more details.
Re claim 16. The device of claim 15, comprising an enrichment layer 104 (e.g., fig. 4 or an upper portion of 104) at a surface of the first layer, the enrichment layer having the first conductivity type (e.g., n-type, fig. 4).
Re claim 17. The device of claim 16, comprising a gate dielectric 108 on the surface of the first layer and a gate 109 on the gate dielectric 108 (e.g., fig. 4).
Re claim 18. The device of claim 17, comprising a source contact 111 on the gate and a drain contact 112 on the substrate, the drain contact 112 spaced from the first and second body well 103 by the first and second floating pocket 106 (e.g., fig. 4).
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 2-3, 5 and 7-11 are rejected under 35 U.S.C. 103 as being unpatentable over Chi et al., US Pub. No. 2021/0391416 A1.
Chi et al. disclosed above and further shows the semiconductor body includes a first epitaxial layer 102 (e.g., the lower portion of 102), having the first conductivity type (e.g., n-type, fig. 4) and a first doping level (fig. 4), and a second epitaxial layer 102 (an upper portion of 102, e.g., the portion above element 106), having the first conductivity type (e.g., n-type, fig. 4) and a second doping level (fig. 4); the body wells 103 are in the second epitaxial layer; and the floating pockets 106 are in the first epitaxial layer (fig. 4). However, Chi et al. does not explicitly show the second doping level is higher than the first doping level (Re claim 2).
The concentration/doping level range of claim 2 is considered to involve routine optimization while has been held to be within the level of ordinary skill in the art. As noted in In re Aller, the selection of reaction parameters such as temperature and concentration would have been obvious:
“Normally, it is to be expected that a change in temperature, or in concentration, or in both, would be an unpatentable modification. Under some circumstances, however, changes such as these may impart patentability to a process if the particular ranges claimed produce a new and unexpected result which is different in kind and not merely degree from the results of the prior art...such ranges are termed Acritical ranges and the applicant has the burden of proving such criticality.... More particularly, where 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 105 USPQ233, 255 (CCPA 1955). See also In re Waite 77 USPQ 586 (CCPA 1948); In re Scherl 70 USPQ 204 (CCPA 1946); In re Irmscher 66 USPQ 314 (CCPA 1945); In re Norman 66 USPQ 308 (CCPA 1945); In re Swenson 56 USPQ 372 (CCPA 1942); In re Sola 25 USPQ 433 (CCPA 1935); In re Dreyfus 24 USPQ 52 (CCPA 1934).
Therefore, one of ordinary skill in the requisite art before the invention was made would have used any concentration/doping level range suitable to the device of Chi et al. in order to optimize the performance of the device etc. Further in this regard, the specification contains no disclosure of either the critical nature of the claimed arrangement (i.e. - the second doping level is higher than the first doping level) or any unexpected results arising therefrom. Where patentability is said to be based upon particular chosen limitations or upon another variable recited in a claim, the Applicant must show that the chosen limitations are critical. In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990).
Re claim 3. The device according to claim 2 wherein the floating pockets 106 (e.g., fig. 4) are at an interface of the first epitaxial layer (e.g., lower portion of 102) with the second epitaxial layer (e.g., upper portion of 102).
Re claim 5. The device according to claim 4 wherein a protection-to-body distance between the floating pockets 107 (e.g., the portion other than the contacting portion) and the corresponding body wells 103 in a direction perpendicular to the first face and to the second face of the semiconductor body is less than 0.5 µm (e.g., fig. 4). Although the exact recitation “is less than 0.5 μm” of the instant claim is not explicitly stated by Chi et al. in the related text, it appears that the protection-to-body distance of the cited prior art is less than 0.5 μm. Therefore, the instant claim appears to be Prima Facie obvious over Chi et al.
Re claim 7. The device according to claim 3 wherein the semiconductor body 102 comprises an intermediate epitaxial layer (e.g., the mid portion of 102 between 106 and 103; fig. 4), arranged between the first epitaxial layer (e.g., the lower portion of 102) and the second epitaxial layer (e.g., the upper portion of 102) and having a doping level (fig. 4). However, Chi et al. does not explicitly show the intermediate epitaxial layer having a doping level intermediate between the first doping level and the second doping level.
The concentration/doping level range of claim 7 is considered to involve routine optimization while has been held to be within the level of ordinary skill in the art. As noted in In re Aller, the selection of reaction parameters such as temperature and concentration would have been obvious:
“Normally, it is to be expected that a change in temperature, or in concentration, or in both, would be an unpatentable modification. Under some circumstances, however, changes such as these may impart patentability to a process if the particular ranges claimed produce a new and unexpected result which is different in kind and not merely degree from the results of the prior art...such ranges are termed Acritical ranges and the applicant has the burden of proving such criticality.... More particularly, where 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 105 USPQ233, 255 (CCPA 1955). See also In re Waite 77 USPQ 586 (CCPA 1948); In re Scherl 70 USPQ 204 (CCPA 1946); In re Irmscher 66 USPQ 314 (CCPA 1945); In re Norman 66 USPQ 308 (CCPA 1945); In re Swenson 56 USPQ 372 (CCPA 1942); In re Sola 25 USPQ 433 (CCPA 1935); In re Dreyfus 24 USPQ 52 (CCPA 1934).
Therefore, one of ordinary skill in the requisite art before the invention was made would have used any concentration/doping level range suitable to the device of Chi et al. in order to optimize the performance of the device etc. Further in this regard, the specification contains no disclosure of either the critical nature of the claimed arrangement (i.e. - the intermediate epitaxial layer having a doping level intermediate between the first doping level and the second doping level) or any unexpected results arising therefrom. Where patentability is said to be based upon particular chosen limitations or upon another variable recited in a claim, the Applicant must show that the chosen limitations are critical. In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990).
Re claim 8. The device according to claim 7, comprising intermediate floating pockets 107 (e.g., fig. 4) having the second conductivity type (e.g., p-type), in the intermediate epitaxial layer (e.g., the mid portion of 102 between 106 and 103; fig. 4) at an interface with the second epitaxial layer (e.g., the upper portion of 102).
Re claim 9. The device according to claim 2 wherein the enrichment layer (e.g., an upper portion of 104, fig. 4) has a third native doping level (e.g., n+) higher than the first doping level (e.g., n-) and the second doping level (e.g., n-) and wherein the first epitaxial layer 102 (e.g. lower portion of 102) has a first thickness, the second epitaxial layer (e.g., upper portion of 102) has a second thickness, and the enrichment layer (e.g., a top portion of 104) has a third thickness smaller than the first thickness and the second thickness (fig. 4).
Re claim 10. The device according to claim 1 wherein the floating pockets 106 are arranged underneath corresponding body wells 103 and are separated from one another by a protection distance greater than the body distance (e.g., fig. 4).
The distance range of claims 10-11 considered to involve routine optimization while has been held to be within the level of ordinary skill in the art. As noted in In re Aller, the selection of reaction parameters such as thickness, distance, temperature and concentration etc. would have been obvious:
“Normally, it is to be expected that a change in temperature, or in concentration, or in both, would be an unpatentable modification. Under some circumstances, however, changes such as these may impart patentability to a process if the particular ranges claimed produce a new and unexpected result which is different in kind and not merely degree from the results of the prior art...such ranges are termed Acritical ranges and the applicant has the burden of proving such criticality.... More particularly, where 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 105 USPQ233, 255 (CCPA 1955). See also In re Waite 77 USPQ 586 (CCPA 1948); In re Scherl 70 USPQ 204 (CCPA 1946); In re Irmscher 66 USPQ 314 (CCPA 1945); In re Norman 66 USPQ 308 (CCPA 1945); In re Swenson 56 USPQ 372 (CCPA 1942); In re Sola 25 USPQ 433 (CCPA 1935); In re Dreyfus 24 USPQ 52 (CCPA 1934).
Therefore, one of ordinary skill in the requisite art before the invention was made would have used any body distance range suitable to the device of Chi et al. in order to optimize the performance of the device etc. Further in this regard, the specification contains no disclosure of either the critical nature of the claimed arrangement (i.e. – the recited range) or any unexpected results arising therefrom. Where patentability is said to be based upon particular chosen limitations or upon another variable recited in a claim, the Applicant must show that the chosen limitations are critical. In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JACK CHEN whose telephone number is (571)272-1689. The examiner can normally be reached Monday to Friday, 8am to 4pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Yara J. Green can be reached at (571)270-3035. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JACK S CHEN/Primary Examiner, Art Unit 2893
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