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 .
DETAILED ACTION
Applicant’s response of 12/16/2025 has been entered in the record and considered.
Applicant’s arguments with respect to the rejection claims 1-3 under 35 USC 103 have been considered but they are not persuasive for the reasons as discussed below. Claims 1-3 are under consideration.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 12/16/2025 has been entered.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-2 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub # 2014/0061875 to Ogura et al.
Regarding independent claim 1, Ogura discloses a semiconductor device (Fig. 1A: 1), comprising:
a semiconductor substrate (Fig. 1A: 10; it is noted that the semiconductor substrate 10 is analogous to the applicant’s own semiconductor substrate; see ¶0104);
an anode electrode (16), formed on a surface on one side of the semiconductor substrate (10);
a cathode electrode (11), formed on a surface on the other side of the semiconductor substrate (10);
a P layer (15), formed on the anode electrode side (16) in the semiconductor substrate (10); and
an N layer (13b), formed on the cathode electrode side (11) in the semiconductor substrate (10) and on the other side of the P layer (15),
wherein the P layer (15) is positioned on a side of the N layer (13b) opposite to the cathode electrode (11) side, and the cathode electrode (11) completely covers the entire surface of the N layer (13b is only formed between N layer 12, therefore, the cathode electrode (11) completely covers the entire surface of the N layer; also see Examiner’s Mark-up below) opposite to the P layer (15),
wherein the cathode electrode (11) and the N layer (13b) are Schottky-junctioned (see at least ¶0058 and Fig. 1A, also see the Examiner’s Mark-up below),
wherein the cathode electrode (11) is a metal having work function ranging from 4.2 eV to 4.3 eV (it is noted that the metal of the claimed cathode electrode is analogous to the applicant’s own metal for the cathode electrode which is aluminum; see ¶0050).
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Ogura teaches the carrier concentration of the N layer (13) is not more than 3 x 1017 cm-3 (¶0058). However, Ogura does not explicitly disclose the ranges from 1 x e12 to 1 x e 18/cm.
Ogura teaches an overlapping range for the carrier concentration of the N layer (13 in ¶0058) such that a prima facie case of obviousness exists (MPEP §2144.05.I). Additionally, as it was known in the art to use a carrier concentration for N layer (13), it would have been obvious to one of ordinary skill in the art at the time of the invention to vary, through routine experimentation, the carrier concentration in order to optimize the functionality of the device (see MPEP §2144.05). Further, the specification contains no disclosure of either the critical nature of the claimed carrier concentration or any unexpected results arising therefrom and it has been held that where patentability is said to be based upon a particular chosen dimension or upon another variable recited in a claim, the Applicant must show that the chosen dimension is critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990).
Regarding independent claim 1, Ogura discloses a semiconductor device (Fig. 25A), comprising:
a semiconductor substrate (Fig. 25A: the combinations of 13-15);
an anode electrode (16), formed on a surface on one side of the semiconductor substrate (10);
a cathode electrode (11), formed on a surface on the other side of the semiconductor substrate (10);
a P layer (15), formed on the anode electrode side (16) in the semiconductor substrate (10); and
an N layer (13), formed on the cathode electrode side (11) in the semiconductor substrate and on the other side of the P layer (15),
wherein the P layer (15) is positioned on a side of the N layer (13b) opposite to the cathode electrode (11) side, and the cathode electrode (11) completely covers the entire surface of the N layer (13b is only formed between N layer 12, therefore, the cathode electrode (11) completely covers the entire surface of the N layer; also see Examiner’s Mark-up below) opposite to the P layer (15),
wherein the cathode electrode (11) and the N layer (13, cathode layer) are Schottky-junctioned (¶0216 and 0220),
wherein the cathode electrode (11) is a metal having work function ranging from 4.2 eV to 4.3 eV (it is noted that the metal of the claimed cathode electrode is analogous to the applicant’s own metal for the cathode electrode which is aluminum; see ¶0050).
Ogura teaches the carrier concentration of the N layer (13) is not more than 3 x 1017 cm-3 (¶0058). However, Ogura does not explicitly disclose the ranges from 1 x e12 to 1 x e 18/cm.
Ogura teaches an overlapping range for the carrier concentration of the N layer (13 in ¶0058) such that a prima facie case of obviousness exists (MPEP §2144.05.I). Additionally, as it was known in the art to use a carrier concentration for N layer (13), it would have been obvious to one of ordinary skill in the art at the time of the invention to vary, through routine experimentation, the carrier concentration in order to optimize the functionality of the device (see MPEP §2144.05). Further, the specification contains no disclosure of either the critical nature of the claimed carrier concentration or any unexpected results arising therefrom and it has been held that where patentability is said to be based upon a particular chosen dimension or upon another variable recited in a claim, the Applicant must show that the chosen dimension is critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990).
Regarding claim 2, Ogura discloses wherein the metal of the cathode electrode (11) comprises aluminum or an aluminum-silicon alloy as a main component (¶0050).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over US Pub # 2014/0061875 to Ogura et al. in view of US Pub # 2003/0218230 to Takahashi et al.
Regarding claim 3, Ogura discloses wherein the semiconductor substrate (10) includes a semiconductor layer 14 which the semiconductor layer 14 includes silicon (¶0060). Ogura fails to explicitly disclose wherein the semiconductor substrate comprises a silicon wafer.
Takahashi teaches it was known in the art to use silicon wafer for a semiconductor substrate (¶0044 and Fig. 3) and it would have been obvious to one of ordinary skill in the art at the time of the invention to have selected silicon wafer for the undisclosed semiconductor substrate as mere selection of an art recognized semiconductor substrate suitable for the intended use of Takahashi (MPEP §2144.07).
Response to Arguments
Applicant's arguments filed 12/16/2025 have been fully considered but they are not persuasive.
Applicants argued in pages 5 of 7 that “Paragraph [0057] of Ogura states." The n cathode layer 13 is disposed on the n+ cathode layer 12 and the cathode electrode 11. Accordingly, the n cathode laver 13 includes a part 13a disposed on the n+ cathode laver 12 and a part 13b in contact with the cathode electrode 11. "
Apparently, the cathode electrode 11 of Ogura only partially covers the surface of the n cathode layer 13 opposite to the p+ anode layer 15, which is positioned on one side of the layer 13b.
However, in response, the Examiner respectfully disagrees.
Paragraph [0057] of Ogura explains that the n-cathode layer 13 is disposed on the n+ cathode layer 12 and that a portion 13b of the n-cathode layer 13 is in contact with the cathode electrode 11. When Ogura is read in view of the figure 1A and the surrounding disclosure, the phrase “entire surface of the n-cathode layer 13b” reasonably refers to the entire electrode-facing surface of portion 13b that is positioned between the n+ cathode layer 12 and the cathode electrode 11, rather than every geometrical surface of layer 13b such as sidewalls or other non-electrode-facing regions.
In other words, Ogura’s teaching concerns the interface surface that functionally cooperates with the cathode electrode, not unrelated or exposed surfaces that do not participate in the electrical contact. Figure 1A further illustrate that the cathode electrode 11 is arranged so as to extend across and contact the full extent of the relevant upper interface of portion 13b. Accordingly, Ogura teaches that the cathode electrode 11 completely covers the entire electrode-facing surface of the n-cathode layer portion 13b, even if the electrode does not extend over side surfaces or other regions that are not part of the operative electrode interface.
Applicant’s interpretation would require “entire surface” to encompass all possible exterior surfaces of layer 13b irrespective of function or context, which is inconsistent with a reasonable reading of Ogura as a whole. Therefore, Ogura is properly understood as disclosing complete coverage of the relevant surface of n-cathode layer portion 13b by the cathode electrode 11.
Applicant further argued in pages 6 of 7 that “In contrast, in the claimed invention, the cathode electrode completely covering the entire surface of the N layer forms a Schottky junction with the N layer, which provides the technical effects: "the quantity of electrons injected from the cathode electrode 22 side to the N laver 14 can be appropriately controlled, the recovery loss can be suppressed, and a forward voltage drop VF of the semiconductor device 10, which is used as a diode in this example, can be maintained relatively small" (please see lines 26-30 of the specification of the subject application). Ogura, in which the cathode electrode 11 only partially covers the surface of the n cathode layer 13, does not appear to teach or suggest these technical effects.
In addition, regarding the claimed feature that "the carrier concentration of the N layer ranges from 1 x e12 to 1 x e18/cm3," which the examiner concedes Ogura fails to explicitly disclose, line 27 on page 6 to line 6 on page 7 of the specification of the subject application describes the technical effects as follows: "If the carrier concentration becomes higher than a certain degree, the forward voltage drop VF decreases but the recovery loss Err increases. It can be seen that if the carrier concentration is 1 x e18/cm3 or less, both the forward voltage drop VF and the recovery loss Err can be maintained in a stable state. Moreover, in order to maintain the function as a diode, the carrier concentration is preferably set to 1 x e12 ~ or more, and thus it can be seen that the carrier concentration is preferably within the range of 1 x e12 to 1 x e18/cm3." As
such, the configuration and operation of the claimed invention are clearly different from those described in Ogura.”
However, in response, the Examiner respectfully disagrees.
Applicant’s argument regarding the claimed carrier concentration range of the N layer is not persuasive. While Applicant asserts that the range of 1 × 10¹² to 1 × 10¹⁸ /cm³ provides certain technical effects, Applicant has not provided sufficient objective evidence demonstrating that this particular range is critical or yields results that are unexpected relative to what would have been obtained through routine optimization.
The specification passages cited by Applicant merely describe general trends (e.g., forward voltage drop and recovery loss varying with carrier concentration) and do not establish that the claimed endpoints or the claimed span represent a point of criticality, a threshold phenomenon, or a region producing results that are qualitatively different from neighboring values. Absent comparative data, experimental results, or other objective evidence showing that the claimed range achieves a new or unexpected property, the argument amounts to attorney assertion rather than persuasive technical proof.
As set forth in MPEP §2144.05(III)(A), discovering an optimum or workable range of a result-effective variable is ordinarily within the level of ordinary skill in the art. Where the prior art recognizes that a parameter affects device performance, selecting or optimizing a value or range through routine experimentation is generally considered obvious unless Applicant demonstrates criticality or unexpected results for the claimed range. Here, Applicant has not shown that the claimed carrier concentration range produces a result that is different in kind, rather than degree, from adjacent or overlapping concentrations, nor has Applicant established that the claimed limits are anything other than an optimization of a known performance-affecting parameter.
Accordingly, in the absence of evidence establishing criticality or unexpected results, the claimed carrier concentration range is reasonably viewed as the product of routine optimization of a result-effective variable, and Applicant’s argument does not overcome the rejection.
The rest of the Applicant’s arguments are substantially the same as those previously addressed on previous Final rejection dated 10/01/2025. In the absence of new evidence or persuasive reasoning, further discussion is not necessary and the prior conclusions are maintained.
It is also noted that the claim is limited to the elements expressly recited. The presence of additional, unclaimed features in the prior art does not distinguish over the claim.
It is for the above discussed reasons that the rejection as applied is considered proper.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). 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 nonprovisional extension fee (37 CFR 1.17(a)) 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 mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOHSEN AHMADI whose telephone number is (571)272-5062. The examiner can normally be reached M-F: 9:00am-5:00pm.
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/MOHSEN AHMADI/Primary Examiner, Art Unit 2896