Ex Parte Storck et alDownload PDFPatent Trial and Appeal BoardJul 12, 201814114056 (P.T.A.B. Jul. 12, 2018) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 14/114,056 10/25/2013 22045 7590 07/16/2018 BROOKS KUSHMAN P.C. 1000 TOWN CENTER TWENTY-SECOND FLOOR SOUTHFIELD, MI 48075 UNITED ST A TES OF AMERICA FIRST NAMED INVENTOR Peter Storck UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www .uspto.gov ATTORNEY DOCKET NO. CONFIRMATION NO. WSAGNOl l lPUSA 1855 EXAMINER BRATLAND JR, KENNETH A ART UNIT PAPER NUMBER 1714 NOTIFICATION DATE DELIVERY MODE 07/16/2018 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): docketing@brookskushman.com kdilucia@brookskushman.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte PETER STORCK, GUENTER SACHS, UTE ROTHAMMER, SARAD BAHADUR TRAP A, HELMUT SCHWENK, PETER DREIER, FRANK MUEMMLER, and RUDOLF MA YRHUBER Appeal2017-009390 Application 14/114,056 Technology Center 1700 Before ROMULO H. DELMENDO, BEYERL YA. FRANKLIN, and RAEL YNN P. GUEST, Administrative Patent Judges. DELMENDO, Administrative Patent Judge. DECISION ON APPEAL The Applicants (hereinafter "Appellants") 1 appeal under 35 U.S.C. § 134(a) from the Primary Examiner's final decision to reject claims 12, 14-- 18, 20, and 23-28. 2 We have jurisdiction under 35 U.S.C. § 6(b). We reverse. 1 The Appellants identify the real party in interest as "Siltronic AG" (Appeal Brief filed February 14, 2017, hereinafter "Appeal Br.," 1). 2 Appeal Br. 3-26; Reply Brief filed June 20, 2017, hereinafter "Reply Br.," 1-13; Final Office Action entered August 19, 2016, hereinafter "Final Act.," 2-16; Examiner's Answer entered April 20, 2017, hereinafter "Ans.," 2-9. Appeal2017-009390 Application 14/114,056 I. BACKGROUND The subject matter on appeal relates to a layered semiconductor substrate and to a method for its manufacture (Specification filed October 25, 2013, hereinafter "Spec.," 1, 11. 3---6). According to the Appellants, in the deposition of a group III nitride layer on a silicon substrate, a material mismatch between the group III nitride layer and silicon results in a difference in thermal expansion coefficients, thereby causing extensive concave bowing of the wafer during cool-down from the group III nitride deposition temperature to room temperature (id. at 1, 11. 8-20). The Appellants state that the invention solves this problem by "provid[ing] a high-quality group III nitride layer having a small bow, the production of which is less time-consuming than the known structures" (id. at 2, 11. 31-34). Figures 2 and 3 are reproduced from the Appellants' Drawings as follows: Fig.2 Fig. 3 2 Appeal2017-009390 Application 14/114,056 Figure 2 above depicts an intermediate product of a layered semiconductor substrate prior to deposition of a Group III nitride layer, wherein the intermediate product includes a monocrystalline first layer 1 and a monocrystalline second layer 2 provided in a convex reverse strain to compensate for the cooling forces of the Group III nitride layer (Spec. 5, 11. 9-12, 22-23, 32-33, 6, 11. 9-15, 7, 11. 17-21). Figure 3 above depicts the layered semiconductor substrate in accordance with the Appellants' invention comprising the first and second monocrystalline silicon layers 1 and 2, an optional intermediate layer 3, and a monocrystalline third layer 4 consisting of a Group III nitride (id. at 5, 1. 14--17-7, 1. 2). Representative claim 12 is reproduced from the Appeal Brief (Claims Appendix 1 ), with key limitations emphasized, as follows: 12. A layered semiconductor substrate comprising a) a monocrystalline first layer ( 1) containing at least 80 % silicon and having a first thickness and a first lattice constant (a1), the first lattice constant (a1) being determined by a first dopant element and a first dopant concentration and b) a monocrystalline second layer (2) containing at least 80 % silicon and having a second thickness and a second lattice constant ( a2), the second lattice constant ( a2) being determined by a second dopant element and a second dopant concentration, the second layer (2) being in direct contact with the first layer, and c) a monocrystalline third layer ( 4) comprising a group III nitride, such that the second layer is located between the first layer and the third layer, wherein the second lattice constant ( a2) is larger than the first lattice constant (a1), wherein the crystal lattice of the first layer (1) and the second layer (2) are lattice-matched so that the second layer (2) is strained, and wherein the bow of the layered semiconductor substrate is in the range from -50 µm to 50 µm, and 3 Appeal2017-009390 Application 14/114,056 wherein the first and second dopant elements are identical and have a smaller covalent atomic radius than silicon, or wherein the first and second dopant element is antimony, or wherein the first dopant element has a smaller covalent atomic radius than silicon and the second dopant element has a larger covalent atomic radius than silicon. II. REJECTIONS ON APPEAL On appeal, the Examiner maintains three rejections under pre-AIA 35 U.S.C. § I03(a) as follows: A. Claims 12, 14--17, 20, 23, and 25-28 as unpatentable over Piner et al. 3 (hereinafter "Piner") in view of Lin et al. 4 (hereinafter "Lin"); 5 B. Claim 18 as unpatentable over Piner in view of Lin and further in view of Cha; 6 and C. Claim 24 as unpatentable over Piner in view of Lin and further in view of Official Notice. (Ans. 2-9; Final Act. 2-15.) 3 US 2003/0132433 Al, published July 17, 2003. 4 Wen Lin et al., "Misfit Stress in PIP+ Epitaxial Silicon Wafers: Effect and Elimination," VLSITSA 5 7---60 (1991). 5 In the Final Office Action (Final Act. 2), the Examiner incorrectly relies on 35 U.S.C. § 102(b) as the statutory basis for Rejection A, which is grounded on obviousness. That error, however, was corrected in the Advisory Action entered December 7, 2016, as the Appellants acknowledge (Appeal Br. 5, n. 5). The Appellants do not allege that the error was prejudicial, and, therefore, it was harmless. 6 US 2010/0155728 Al, published June 24, 2010. 4 Appeal2017-009390 Application 14/114,056 III. DISCUSSION The Examiner finds that Piner describes a layered semiconductor substrate that includes most of the limitations recited in claim 12 (Final Act. 3--4). The Examiner states that "[s]ince the semiconductor material (10) of Piner has the claimed structure[,] it must necessarily exhibit the same properties, namely a bow of -50 µm to 50 µm" (id. at 4) (citing In re Best, 562 F.2d 1252, 1255 (Fed. Cir. 1977)). To account for one of the three alternative dopant elements limitations highlighted above in reproduced claim 12, the Examiner finds that Piner's layer 14 corresponds to Appellants' first layer (1) with 0% Ge dopant (id. at 3). The Examiner also finds that Piner's layer 12 corresponds to the Appellants' second layer (2) and includes Ge dopant, which, in the Examiner's view, corresponds to the Appellants' second dopant element having a larger covalent radius than silicon (id. at 3, 4). The Examiner acknowledges, however, that Piner does not teach a first dopant element having a smaller covalent atomic radius than silicon, as required by claim 12 (id. at 4). Nevertheless, the Examiner concludes that the use of such a dopant ( e.g., boron or phosphorus) in Piner's layer 14 would have been obvious to a person having ordinary skill in the art in view of Lin (id. at 4--5; Ans. 4--5). The Appellants contend that "there is no clear and particular evidence of motivation to combine" Piner and Lin (Appeal Br. 5). According to the Appellants, "a reference which does not even mention the problem addressed by a patent applicant cannot suggest a solution, and cannot render the claims unpatentable, whether considered alone or in combination with other references" (id.). The Appellants also argue, inter alia, that "[t]he claims also require that concentrations of non-silicon (dopant) atoms in the 5 Appeal2017-009390 Application 14/114,056 first and second layers alter the lattice constants of these layers relative to each other in the manner set forth in claim 12," which does not allow for both the first and second dopants to be Ge (id. at 7). Specifically, the Appellants argue that Piner "does not teach lattice-matching of [the first and second Si-based] layers, and as a dopant, mentions only germanium, a dopant having a larger lattice constant than does silicon" (id. at 8). According to the Appellants, Piner teaches the use of germanium dopant for a specific reason-i.e., "to match the thermal coefficients of expansion of his silicon/germanium layer and his Group III nitride layer" and, thus, "there would be no motivation to combine Piner with any reference which discloses the use of other dopants not having this higher coefficient of thermal expansion" (id. at 8) (underlining omitted). We disagree with the Appellants' position that an obviousness conclusion is precluded unless the prior art addresses the same problem and solution. KSR Int 'l Co. Teleflex Inc., 550 U.S. 398, 420 (2007) ("The first error of the Court of Appeals in this case was to foreclose [an obviousness] reasoning by holding that ... patent examiners should look only to the problem the patentee was trying to solve."). "Under the correct analysis, any need or problem known in the field of endeavor at the time of invention and addressed by the [prior art] can provide a reason for combining the elements in the manner claimed." Id. See also In re Kemps, 97 F.3d 1427, 1430 (Fed. Cir. 1996) (the motivation or reason in the prior art need not be the same as that of the applicant). Notwithstanding our disagreement with the Appellants on the problem-solution approach in analyzing obviousness, we concur with the Appellants that the Examiner's rejection fails to articulate a sufficient reason 6 Appeal2017-009390 Application 14/114,056 with some rational underpinning to support a conclusion that a person of ordinary skill in the art would have combined Piner and Lin in the manner claimed by the Appellants. KSR, 550 U.S. at 418 (citing In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006)). Piner's Figure 1 is reproduced as follows: I . tL· ~-----------·-···--···----·--·--····-----~ to i ! i I \ 'a. 1--~--- ! \i . - ___ c I !l. . L _____________________________________________________________________ ! 1( ;o, \ ,J' Piner's Figure 1 above depicts a semiconductor material 10 including a silicon-germanium layer 12 formed on a substrate 14 and a gallium nitride layer 16 formed on the silicon-germanium layer 12 (Piner ,r 22). As pointed out above, the Examiner appears to consider Piner' s substrate 14 and silicon-germanium layer 12 in Piner's Figure 1 as the Appellants' mono crystalline first layer 1 and monocrystalline second layer 2, as shown in the Appellants' Figures 2 and 3, respectively (Final Act. 3). Piner teaches that the silicon-germanium layer 12 may be formed of any SixGe(l-x), wherein OCopy with citationCopy as parenthetical citation