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 .
Response to Amendment
Amendment dated 10/02/2025 has been acknowledged. Claim 1, 9 & 10 are currently amended. Claims 10-15 were previously withdrawn. Claims 1-15 remain pending in applications.
Response to Arguments
Applicant’s argument dated 10/02/2025 has been acknowledged but are not persuasive since redefining claimed “a protruding structure” including protruding portion of 103 & Schottky contact 107 (as annotated in Zhang , Fig. 3 below), the upper electrode 106 is in physical contact with 107, and hence with the protruding structure. Therefore, Zhang still reads on the amended limitation “wherein the upper electrode layer is in physical contact with the protruding structure” (see associated claim 1 rejection below).
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Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 1-8 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Zhang (CN-112909076-A)
Regarding claim 1, Zhang teaches,
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A semiconductor structure, comprising:
a substrate having a first conductivity type (N + substrate 102);
an epitaxial layer disposed on the substrate and having the first conductivity type (N-drift layer 103), wherein there is a protruding structure (including 107 & protruding portion of 103) on an upper portion of the epitaxial layer;
a well region (P type 104) disposed in the epitaxial layer , wherein the well region has a second conductivity type (P type);
an insulating structure (field plate dielectric layer 105) disposed on a sidewall of the protruding structure (as seen);
an upper electrode layer (field plate metal 106) surrounding the protruding structure (as seen) and electrically connected to the epitaxial layer (via schottky contact 107) and the well region (in contact with 104),
wherein the upper electrode layer (106) is in physical contact with the protruding structure (in physical contact with portion 107 of the protruding structure as defined);
and a lower electrode layer (bottom ohmic contact 101) disposed under the substrate and opposite to the epitaxial layer(as seen).
Regarding claim 2, Zhang teaches the semiconductor structure of claim 1 and further teaches , wherein the insulating structure (105) is located between the protruding structure and the upper electrode layer (106).
Regarding claim 3, Zhang teaches the semiconductor structure of claim 1 and further teaches , wherein there is a trench structure (as marked) surrounding the protruding structure on the upper portion of the epitaxial layer (103), and the upper electrode layer (106) is filled in the trench structure (as seen).
Regarding claim 4, Zhang teaches the semiconductor structure of claim 1 and further teaches , wherein a portion of the insulating structure (portion of 105 in contact with 104) extends between the well region (104) and the upper electrode layer (106) .
Regarding claim 5, Zhang teaches the semiconductor structure of claim 1 and further teaches , wherein the epitaxial layer comprises silicon carbide (N-drift layer 103 maybe Si, SiC, GaN or Ga2O3).
Regarding claim 6, Zhang teaches the semiconductor structure of claim 1 and further teaches, wherein the substrate comprises silicon or silicon carbide (N + substrate 102 maybe Si, SiC, GaN or Ga2O3)
Regarding claim 7, Zhang teaches the semiconductor structure of claim 1 and further teaches, wherein a dopant concentration in the epitaxial layer is lower than a dopant concentration in the substrate (doping concentration of N-drift layer 103 maybe 1.0x1015/cm3 to 8.0x1016/cm3 lower than the dopant concentration of N substrate 102 which maybe 1.0x1018/cm3 to 5.0x1019/cm3).
Regarding claim 8, Zhang teaches the semiconductor structure of claim 1 and further teaches , wherein the insulating structure comprises an oxide (material of the field plate dielectric layer 105 maybe SiO2, SiN, Al2O3 or HfO2) having an element (Si) in common with the epitaxial layer(material of the drift layer 103 may be Si, SiC, GaN or Ga2O3).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 teaches d 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 9 is rejected under 35 U.S.C. 103 as being unpatentable over Zhang and further in view of SHIMIZU (US 2022/0262916 A1).
Regarding claim 9, Zhang teaches the semiconductor structure of claim 1 but does not explicitly teach, further comprising a silicide layer located at an interface between the well region and the upper electrode layer.
But SHIMZU teaches,
A silicide layer (13) at an interface between the well region ( p-well 32) and the upper electrode (12). Since the metal silicide layer 13 is used, the contact resistance between the p-well contact region 32 and the upper electrode 12 are reduced (see para [0105], FIG. 1).
Thus, it would have been obvious to one in ordinary skill in art before the effective filing date of the claimed invention to modify Zhang such that a silicide layer (metal silicide layer 13) located at an interface between the well region (104/32) and the upper electrode layer (106/12), according to teaching of SHIMIZU above, in order to reduce the contact resistance between P-well 104 contact region and upper electrode 106, as taught by SHIMIZU above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 extension fee 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 date of this final action. (FP 7.40)
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/K.A.R/Examiner, Art Unit 2813
/STEVEN B GAUTHIER/Supervisory Patent Examiner, Art Unit 2813