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 Group I, claim 1-15 in the reply filed on 05/14/2026 is acknowledged.
Status of the Application
Claims 1-20 remain pending in this application. Claims 16-20 are withdrawn.
Priority
Acknowledgment is made of applicant's claim for foreign priority based on an application filed in Korea on 01/13/2023. It is noted, however, that applicant has not filed a certified copy of the KR10-2023-0005588 application as required by 37 CFR 1.55. Receipt is acknowledged of a certified copy of the KR10-2023-0177225 application as required by 37 CFR 1.55.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
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 9, 10, 14, and 15 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.
Regarding claim 9, the claim recites “a length of a cross-sectional area of the peripheral contact region is determined according to a preset ratio based on a length of a cross-sectional area of the charge sharing region in the peripheral region”, which does not adequately define the metes and bounds of the claim, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. One of ordinary skill in the art would only conclude that certain exemplary embodiments qualify, but without a definite criterion by which to ascertain whether any non-disclosed embodiments so qualifies. For example, it is unclear if the claim is intended to limit “a preset ratio” to a specific value, or range of values, or some other limitation. This renders the scope of the claims indefinite. For the purpose of compact prosecution, the Examiner interprets the limitation to mean “a length of a cross-sectional area of the peripheral contact region accounts for 30 to 60% of a length of a cross-sectional area of the peripheral charge sharing region.”
Regarding claim 10, the claim recites “an area of the charge sharing region in the peripheral corner region is determined according to a preset ratio based on an area of the peripheral corner region”, which does not adequately define the metes and bounds of the claim, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. One of ordinary skill in the art would only conclude that certain exemplary embodiments qualify, but without a definite criterion by which to ascertain whether any non-disclosed embodiments so qualifies. For example, it is unclear if the claim is intended to limit “a preset ratio” to a specific value, or range of values, or some other limitation. This renders the scope of the claims indefinite. For the purpose of compact prosecution, the Examiner interprets the limitation to mean “an area of the charge sharing region in the peripheral corner region accounts for 30 to 80% of the area of the peripheral corner region.”
Regarding claims 14 and 15, the claims depend from rejected claim 10, includes all limitations of the claim and therefore is rejected for the same reason. The claims will be examined on the basis of interpretation of the rejected claim hereafter.
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 1-4 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Lee et al (US 20180204936 A1, hereafter Lee).
Regarding claim 1, Lee discloses: A super junction semiconductor device (Lee 100, ¶0002-0004, 0051, fig 1A-1C, 2) comprising:
a substrate (Lee 110, ¶0055-0056);
an active cell (Lee AR, 120, ¶0054-0056) disposed on the substrate (Lee fig 1B, 2);
an edge termination region (Lee TR, ¶0054) surrounding the active cell (Lee fig 1A, 1B);
a peripheral region (Lee “Transition Region”, ¶0080, fig 2) formed between the active cell and the edge termination region (Lee fig 2);
a plurality of first conductivity type pillars (Lee 122, 122A, 136, ¶0058, 0062, 0081, “N-type”) and second conductivity type pillars (Lee 124, 124A, 138, ¶0058, 0062, 0081, “P-type”) alternately provided at an edge of the active cell (Lee 120, 122, 124, fig 2, ¶0057) and the peripheral region (Lee 122A, 124A, fig 2, ¶0080-0081) and the edge termination region (Lee 136, 138, fig 2, ¶0061-0063, 0083)(Lee fig 2); and
a charge sharing region (Lee 192, 140, 150, 160, ¶0066, 0078, 0081, fig 2, under a broadest reasonable interpretation of “charge sharing”) connecting the second conductivity type pillars in the peripheral region (Lee 124A) with the second conductivity type pillars in the edge termination region (Lee 136) above the peripheral region and the edge termination region (Lee fig 2).
Regarding claim 2, Lee discloses: The super junction semiconductor device according to claim 1, wherein the charge sharing region (Lee 192, 140, 150, 160) comprises a peripheral charge sharing region (Lee 192) disposed in the peripheral region (Lee “Transition Region”, ¶0080, fig 2)(Lee fig 2, ¶0080) and an edge termination charge sharing region (Lee 140, 150, 160) disposed in the edge termination region (Lee TR)(Lee fig 2, ¶0064-0066).
Regarding claim 3, Lee discloses: The super junction semiconductor device according to claim 1, further comprising:
a body region of the second conductivity type (Lee 170, ¶0059, “P body region”, P-type) formed on each of the second conductivity type pillars (Lee 124) provided at the edge of the active cell (Lee AR)(Lee fig 2, ¶0059).
Regarding claim 4, Lee discloses: The super junction semiconductor device according to claim 3, further comprising:
source regions of the first conductivity type (Lee 174, ¶0059, “N+ regions”, N-type, at least capable of serving as source regions supplying carriers to a channel) formed in the body region of the second conductivity type (Lee 170)(Lee fig 2, ¶0059); and
a body contact region of the second conductivity type (Lee 172, ¶0059, “P+ region”, P-type) formed between the source regions of the first conductivity type (Lee fig 2, ¶0059).
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 5 is rejected under 35 U.S.C. 103 as being unpatentable over Lee et al (US 20180204936 A1, hereafter Lee), as applied to claim 1 above, and further in view of Yedinak et al (US 20120273871 A1, hereafter Yedinak).
Regarding claim 5, Lee teaches: The super junction semiconductor device according to claim 1.
Lee does not teach: at least one pillar of the second conductivity type provided at an outermost portion of the edge termination region and not connected to the charge sharing region.
Yedinak, in the same field of endeavor of semiconductor device manufacturing, teaches: at least one pillar of a second conductivity type (Yedinak 1940, ¶0110, “P-pillars”, P-type) provided at an outermost portion of an edge termination region (Yedinak 1905, fig 19L, portion of 1905 that does not include 1908 extending towards an outer portion of 1905) and not connected to a charge sharing region (Yedinak 1908, ¶0106, 0110, under a broadest reasonable interpretation of a “charge sharing region”)(Yedinak fig 19L).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Lee to include “at least one pillar of the second conductivity type provided at an outermost portion of the edge termination region and not connected to the charge sharing region”, as taught by Yedinak, in order to distribute the electric field across the termination region without full pillar depletion, thereby avoiding localized reduction of breakdown voltage in the outermost portion of an edge termination region (Yedinak ¶0062-0063).
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al (US 20180204936 A1, hereafter Lee), as applied to claim 4 above, and further in view of Hozumi et al (US 20100032791 A1, hereafter Hozumi).
Regarding claim 6, Lee teaches: The super junction semiconductor device according to claim 4, further comprising:
a field oxide film (Lee 186, ¶0067) formed on the charge sharing region (Lee 192, 140, 150, 160) in the edge termination region (Lee TR)(Lee fig 2, ¶0067); and
a gate insulating film (Lee 176, ¶0059) formed on the source regions (Lee 174) and the plurality of first conductivity type pillars (Lee 122, 122A, 136) in the active cell (Lee AR)(Lee 122)(Lee fig 2, ¶0059).
Lee does not teach: the gate insulating film formed on an end portion and a side surface of the field oxide film toward the peripheral region, and the charge sharing region at an edge of the peripheral region.
Hozumi, in the same field of endeavor of semiconductor device manufacturing, teaches: a gate insulating film (Hozumi 144, ¶0140) formed on an end portion and a side surface of a field oxide film (Hozumi 142, ¶0140, 0148) toward a peripheral region (Hozumi 5, ¶0140, under a BRI of “peripheral region”)(Hozumi fig 8N, ¶0140), and a charge sharing region (Hozumi 130, ¶0140, under a BRI of “charge sharing region”) at an edge of the peripheral region (Hozumi fig 8N, ¶0140).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the gate insulating film of Lee such that it is formed on “an end portion and a side surface of the field oxide film toward the peripheral region, and the charge sharing region at an edge of the peripheral region”, as taught by Hozumi, in order to extend a depletion region into the termination region to prevent electric field concentration at the boundary, thereby enhancing a withstand voltage (Hozumi ¶0026).
Regarding claim 7, Lee in view of Hozumi teaches: The super junction semiconductor device according to claim 6, further comprising:
a gate electrode (Lee 178, ¶0059) formed on the gate insulating film (Lee 176 as modified by Hozumi) in the active cell (Lee AR)(Lee fig 2, ¶0059);
a field plate (Lee 188, ¶0077) formed on the gate insulating film formed over the peripheral region (Lee 176 as modified by Hozumi)(Lee “Transition Region”) and the edge termination region (Lee TR)(Lee fig 2, ¶0077);
a first insulating film (Lee 180, ¶0059) formed on side surfaces and an upper surface of the gate electrode, the field plate, and the field oxide film (Lee 186)(Lee fig 2);
a second insulating film (Lee 182, ¶0059) formed on the first insulating film (Lee fig 2, ¶0059); and
a gate runner (Lee 190, ¶0077, under a BRI of “gate runner”) formed on the field plate and connected to the field plate (Lee fig 2, ¶0077).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Lee et al (US 20180204936 A1, hereafter Lee), as applied to claim 2 above, and further in view of Furuhashi et al (US 20190333988 A1, hereafter Furuhashi).
Regarding claim 8, Lee teaches: The super junction semiconductor device according to claim 2, further comprising:
a peripheral contact region (Lee 172, fig 2, ¶0059, under a BRI of “a peripheral contact region”, 172 is at least in contact with 184 and within the “transition region”) disposed in the peripheral region (Lee “Transition Region”, ¶0080, fig 2)(Lee fig 2);
a source electrode (Lee 184, ¶0059) formed on a body contact region (Lee 172, ¶0059, “P+ region”, P-type) formed between source regions (Lee 174, ¶0059, “N+ regions”, N-type, at least capable thereof) of the active cell (Lee AR) and the peripheral contact region of the peripheral region (Lee fig 2).
Lee does not explicitly teach: the peripheral contact region formed in the peripheral charge sharing region; and
a drain electrode formed under the substrate.
Furuhashi, in the same field of endeavor of semiconductor device manufacturing, teaches: a peripheral contact region (Furuhashi 10b, fig 3, ¶0058) formed in a peripheral charge sharing region (Furuhashi 9, 10b, ¶0058-0060, P-type regions at least capable thereof, pillars 5b/6b being different than 5a/6a within TR);
a source electrode (Furuhashi 15, ¶0096) formed on a body contact region (Furuhashi 10a, ¶0094) formed between source regions (Furuhashi 8, ¶0054) of the active cell (Furuhashi ER, ¶0006) and the peripheral contact region of a peripheral region (Furuhashi, fig 3, a region defined by pillars 5b/6b within TR); and
a drain electrode (Furuhashi 16, ¶0066) formed under a substrate (Furuhashi 3, ¶0053)(Furuhashi fig 3, ¶0066).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the peripheral contact region of Lee such that it is “formed in the peripheral charge sharing region disposed in the peripheral region”, as taught by Furuhashi, in order to provide a discharge path for carriers from the termination region, thereby securing the breakdown voltage of the termination region (Furuhashi ¶0006, 0089, 0099). Further, It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Lee to include the drain electrode of Furuhashi, under the substrate, in order to complete a vertical current conduction path, thereby enabling operation as a vertical power MOSFET (Furuhashi ¶0096).
Allowable Subject Matter
Claims 9, 10, 14, and 15 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Claims 11-13 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.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NICHOLAS B. MICHAUD whose telephone number is (703)756-1796. The examiner can normally be reached Monday-Friday, 0800-1700 Eastern Time.
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/NICHOLAS B. MICHAUD/
EXAMINER
Art Unit 2818
/BRIAN TURNER/Examiner, Art Unit 2818
Prosecution Insights