10867591 (B.P.A.I. May. 28, 2010)

Ex Parte Maydan et al

Board of Patent Appeals and InterferencesMay 28, 2010

10867591 (B.P.A.I. May. 28, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________________ Ex parte DAN MAYDAN and ARKADII V. SAMOILOV ____________________ Appeal 2009-010136 Application 10/867,591 Technology Center 1700 ____________________ Decided: May 28, 2010 ____________________ Before MICHAEL P. COLAIANNI, BEVERLY A. FRANKLIN, and LINDA M. GAUDETTE, Administrative Patent Judges. COLAIANNI, Administrative Patent Judge. DECISION ON APPEAL This is a decision on an appeal under 35 U.S.C. Â§ 134 from the Examiner's final rejection of claims 1 through 32, which are all of the claims pending in the above-identified application. We have jurisdiction pursuant to 35 U.S.C. Â§ 6. We REVERSE. Appeal 2009-010136 Application 10/867,591 2 STATEMENT OF THE CASE The subject matter on appeal is directed to a method of forming a planar waveguide structure. The Examiner maintains the rejections of claims 1-32 under 35 U.S.C. Â§ 103(a) as unpatentable over Liaw (US 5,891,769, issued Apr. 6, 1999), Pogossian ("High-confinement SiGe low-loss waveguides for Si-based optoelectronics," Applied Physics Letters, Vol. 75, No. 10, pp. 1440-1442, (Sept. 6, 1999)), and Domash (US 6,771,857 B1, issued Aug. 3, 2004). ISSUE Did the Examiner err by failing to provide a credible reason for combining Liaw, which is directed to a strained heterojunction semiconductor device, with Pogossian and Domash, which are directed to waveguides, to arrive at the inventions recited in claims 1, 29, and 32 within the meaning of Â§ 103? We decide this issue in the affirmative. FINDINGS OF FACT 1. Liaw teaches a strained heterojunction semiconductor device such as a metal oxide semiconductor field effect transistor (MOSFET) device composed of three SiGe layers. (Liaw, col. 1, ll. 15-51). 2. Pogossian teaches, inter alia, a SiGe waveguide formed within a patterned portion of a substrate. (Pogossian, pp. 1140-1441). 3. Appellants do not specifically dispute the Examiner's finding that Domash "teaches etching the substrate." (Compare Ans. 3 with App. Br. 4-10 and Reply Br. 4-8). In this regard, Domash's Fig. 5a Appeal 2009-010136 Application 10/867,591 3 illustrates waveguides 31a and 31b positioned within the etched portion of substrate 33. (See Fig. 5a and col. 14, ll. 50-59). ANALYSIS AND CONCLUSION We begin by noting that independent claims 1, 29, and 32 require forming a planar waveguide. In addition, independent claims 1 and 29 require "etching a pattern into a substrate." The Examiner states that The Liaw et al reference teaches a method of depositing multi-layers. On a substrate, a layer of silicon-germanium is deposited by low- pressure chemical vapor deposition. The silicon source is silane. The germanium concentration increases in the height of the layer. A layer of constant composition SiGe is deposited on the first layer. Then a third layer of graded SiGe is deposited where the germanium concentration is decreased during the height of the layer, note, entire reference. . . . The Liaw et al reference . . . differs from the instant claims in . . . etching the substrate. [T]he Pogossian et al reference teaches a SiGe [waveguide composed of, inter alia,] . . . graded layers, note, figure 3. The Domash et al reference teaches etching the substrate and then depositing the waveguide, note col. 2. It would have been obvious to one of ordinary skill in the art to modify the Liaw et al process in view of the Pogossian et al and Domash et al references to [inter alia] . . . etch the substrate in order to increase the optical properties of . . . [the] SiGe [waveguide] layers. (Ans. 4). The Examiner also states that The Domash and Pogossian references do teach etching substrates and use of cladding layers in the waveguide manufacturing art. I[t] would have been obvious to combine the references set forth in the rejections in order to create a uniform and specifically placed waveguide in the substrate. (Ans. 5). In other words, it appears that the Examiner concludes that it would have been obvious to employ Liaw's SiGe layers as a waveguide as Appeal 2009-010136 Application 10/867,591 4 suggested by Domash and Pogossian and required by claims 1, 29, and 32 and further concludes that it would have been obvious to form this waveguide within an etched portion of the substrate as suggested by Domash and Pogossian and as required by claims 1 and 29. We disagree. While Liaw at column 1, lines 15 through 44 teaches the steps of forming three SiGe layers, Liaw teaches that these layers are part of a strained heterojunction semiconductor device such as a MOSFET device. (FF 1). In addition, Domash teaches forming a waveguide structure via, inter alia, etching a substrate and then positioning a waveguide to be within the etched portion of a substrate. (FF 3). Similarly, Pogossian teaches a SiGe waveguide comprising SiGe layers formed within a patterned portion of a substrate. (FF 2). Thus, it is unclear to us why one of ordinary skill would have combined the teachings of Liaw, which forms a strained heterojunction semiconductor device such as a MOSFET device, with the teachings of Pogossian and Domash, which form a waveguide structure. In this regard, the Examinerâ€™s conclusion that that it would have been obvious to employ Liaw's SiGe layers as a waveguide as suggested by Domash and Pogossian and further that it would have been obvious to form this waveguide within an etched portion of the substrate as suggested by Domash and Pogossian is based on impermissible hindsight. The Examiner simply directs us to no credible evidence or persuasive reasoning to support such a conclusion. The Examiner's statement that it would have been obvious to "etch the substrate in order to increase the optical properties of . . . [the] SiGe [waveguide] layers" is directed to the second part of this conclusion as it Appeal 2009-010136 Application 10/867,591 5 only provides a reason to employ a waveguide within an etched portion of a substrate. The Examiner, however, does not address the first part of the conclusion regarding why one of ordinary skill would combine Liaw, Domash, and Pogossian such that it would have been obvious to employ Liaw's SiGe layer as a waveguide as suggested by Domash and Pogossian. Indeed, as correctly stated by Appellants, although Pogossian and Domash may teach or suggest the specific limitations asserted by the Examiner, there remains no teaching, suggestion, motivation, or other reasoning to take the strained channel heterojunction device of Liaw (that is only briefly mentioned and is disparaged as having a high concentration of threading dislocations) and combine it with the teachings of Pogossian and Domash as asserted by the Examiner. (App. Br. 7). Thus, it follows that the Examiner erred by failing to provide a credible reason for combining Liaw, which is directed to a strained heterojunction semiconductor device, with Pogossian and Domash, which are directed to waveguides, to arrive at the inventions recited in claims 1, 29, and 32 within the meaning of Â§ 103. ORDER In summary, the rejections made by the Examiner are reversed. REVERSED Cam Appeal 2009-010136 Application 10/867,591 6 MOSER IS LAW GROUP APPLIED MATERIALS, INC. 1030 BROAD STREET 2ND FLOOR SHREWSBURY NJ 07702