Ex Parte Harmon et alDownload PDFPatent Trial and Appeal BoardAug 30, 201610837175 (P.T.A.B. Aug. 30, 2016) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 10/837,175 05/01/2004 7590 08/30/2016 David Garrod c/o LightSpin Technologies, Inc. P.O. Box 30198 Bethesda, MD 20824-0198 FIRST NAMED INVENTOR Eric S. Harmon 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. L24 2179 EXAMINER NADAV,ORI ART UNIT PAPER NUMBER 2811 MAILDATE DELIVERY MODE 08/30/2016 PAPER 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. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte ERIC S. HARMON and DAVID B. SALZMAN Appeal2014-002628 Application 10/837,175 Technology Center 2800 Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and JAMES C. HOUSEL, Administrative Patent Judges. HANLON, Administrative Patent Judge. uECISION ON APPEAL A. STATEMENT OF THE CASE The Appellants filed an appeal under 35 U.S.C. § 134 from a final rejection of claims 86-89 under 35 U.S.C. § 103(a) as unpatentable over Cova et al. 1 in view 1 US 6,384,663 B2, issued May 7, 2002 ("Cova"). Appeal2014-002628 Application 10/837,175 of Chow et al.,2 Pakdaman et al., 3 the Appellants' admitted prior art,4 and Bondarenko et al. 5,6 We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. Independent claim 86 is reproduced below from the Claims Appendix of the Appeal Brief dated October 8, 2013 ("Br."). 86. A monolithically integrated array of photodetector elements connected in a common anode or common cathode configuration to achieve analog summation of the outputs of said photodetector elements, including at least a first photodetector element and a second photodetector element, wherein said first photodetector element includes in series a first SP AD[7J device and a first passive quench circuit element, said first SP AD device further includes a first gain region, and the Geiger mode gain of said first SPAD device is less than 1,000,000; said second photodetector element includes in series a second SPAD device and a second passive quench circuit element, said second SP AD device further includes a second gain region, and the Geiger mode gain of said second SPAD device is less than 1,000,000; said first gain region is formed from a compound semiconductor material with a band gap above 1.3 5 e V[.] Br. 26-27. 2 US 6,609,840 B2, issued August 26, 2003 ("Chow"). 3 US 6,859,031 B2, issued February 22, 2005 ("Pakdaman"). 4 US 2004/0245592, published December 9, 2004, i-f 11 ("592 Application"). 5 G. Bondarenko et al., Limited Geiger-mode Microcell Silicon Photodiode: New Results, 442 Nuclear Instruments and Methods in Physics Research 187-92 (2000) ("Bondarenko"). 6 The Examiner withdrew the rejection of claims 86-89 under 35 U.S.C. § 112, second paragraph, on page 2 of the Examiner's Answer dated October 21, 2013 ("Ans."). 7 Single-proton avalanche detector ("SP AD"). 592 Application i-f 7. 2 Appeal2014-002628 Application 10/837,175 B. DISCUSSION The§ 103(a) rejection on appeal is sustained for the reasons set forth in the Final Office Action dated December 11, 2012 ("Final") and the Examiner's Answer. We add the following comments for emphasis. 1. Claim 86 In the rejection on appeal, the Examiner finds Cova discloses a photodetector element including, in series, a SP AD device and a passive quench circuit element. The Examiner finds Bondarenko discloses the advantages of using a SPAD device having a gain less than 1,000,000 and formed of SiC (i.e., a compound semiconductor material with a band gap above 1.35 e Vas claimed). The Examiner also finds the admitted prior art in the Appellants' Specification teaches that it was known in the art to monolithically connect at least two photodetector SPAD elements in a common anode/cathode configuration. Finally, the Examiner finds Chow and Pakdaman teach that it was known in the art to use various types of compound semiconductor materials for photodetectors and SP AD elements. Based on those findings, the Examiner concludes that the device recited in claim 86 would have been obvious to one of ordinary skill in the art. Ans. 16- 17. First, the Appellants argue that Cova does not teach a monolithically integrated array (at least two) of photodetector elements. Br. 14. Although Cova Figure 2 depicts only one photodetector device and one SP AD device, the Examiner finds Cova refers to a plurality of photodetector elements and a plurality of SPAD devices throughout the disclosure. Ans. 3, 6. Moreover, the Examiner finds, and the Appellants do not dispute, that the admitted prior art in the Appellants' Specification teaches that it is conventional to form a photodetector comprising a two-dimensional array of photodetector elements 3 Appeal2014-002628 Application 10/837,175 connected to a common anode or a common cathode. Ans. 4 (citing 592 Application i-f 11 ). Second, the Appellants argue that Cova does not disclose monolithic integration of SP ADs, SP AD arrays, or individual SP AD elements with monolithically integrated quench circuits. Rather, according to the Appellants, Cova describes "external, discrete circuitry to actively quench a SP AD detector, which is the antithesis of the applicant's teaching that monolithic integration of the passive quench circuit provides superior quenching performance compared to active quenching." Br. 15. In response, the Examiner finds Cova Figure 2 depicts one circuit with one SP AD element being integrated with a quench circuit. See Ans. 6; see also Ans. 8 (finding"' [Cova] FIG. 2 shows a passive quenching circuit of a SPAD photodiode according to the known technique"'); 8 Cova, col. 10, 11. 41--47. The Examiner finds, and the Appellants do not dispute, that the circuit clearly consists of one piece and thus, is a monolithically integrated quench circuit. Ans. 6. Moreover, the Examiner finds the admitted prior art in the Appellants' Specification teaches it was known in the art to employ a monolithically integrated quenching circuitry array of at least two photodetector elements for each pixel and array circuitry in order to combine the output of the array. Ans. 6-7 (citing 592 Application i-f 11). The Appellants do not direct us to any error in the Examiner's finding. Third, the Appellants argue that Pakdaman does not teach using a compound semiconductor with a band gap above 1.35 eV as recited in claim 86. Br. 16. 8 "[A ]ll disclosures of the prior art, including unpreferred embodiments, must be considered." In re Lamberti, 545 F.2d 747, 750 (CCPA 1976). 4 Appeal2014-002628 Application 10/837,175 In the rejection on appeal, the Examiner relies on Chow and Bondarenko, not Pakdaman, to teach the claimed compound semiconductor. See Ans. 8. In particular, the Examiner finds Chow teaches that compound semiconductors, including wider band compound semiconductors such as GaAs,9 were known to be used in photodetectors for telecommunications applications. Ans. 10 (citing Chow, col. 7, 11. 26-31 ). The Examiner finds the only issue is whether a wide band gap compound semiconductor can be used with SP AD devices having a gain less than 1,000,000 as recited in claim 86. Ans. 10. In that regard, the Examiner finds Bondarenko teaches a SP AD device wherein the gain is less than 1,000,000. Ans. 9. The Examiner also finds Bondarenko uses silicon carbide, which has a band gap of 2.36 e V, in the disclosed SP AD device. Thus, the Examiner finds Bondarenko teaches that a compound semiconductor with a band gap above 1.35 e V may be used in a SP AD device having a gain less than 1,000,000 as recited claim 86. Ans. 10. The Appellants do not direct us to any error in the Examiner's findings. Fourth, referring the Examiner's motivation in the rejection on appeal, the Appellants argue that "[u]sing passive quenching with compound semiconductors is not known to provide a better quality photodiode." Br. 19. For support, the Appellants identify four articles but do not discuss the articles in any detail. Br. 19-20. In the rejection on appeal, the Examiner provides several reasons for combining the prior art as proposed: It would have been obvious to a person of ordinary skill in the art at the time the invention was made to connect of the array of photodetector elements in Cova et al. device in a common anode or 9 The Examiner finds GaAs has a band gap above 1.42 eV. Ans. 5. 5 Appeal2014-002628 Application 10/837,175 common cathode configuration to achieve analog summation of the outputs, wherein the Geiger mode gain of said first or second SP AD devices is a less than 1,000,000, and to form said first gain region from a compound semiconductor material with a band gap above l.35eV, in order to simplify the operation of the device by not constraining the density of the pixels, in order to use the device in an application which require specific Geiger mode gain, and in order to improve the device characteristics and to provide [a] better quality photodiode when using the device in a telecommunication application which requires an array, respectively. Final 4--5 (emphasis added); Ans. 4--5 (emphasis added). Thus, the Examiner finds that modifying the Cova device "to form said first gain region from a compound semiconductor material with a band gap above 1.3 5 e V," without regard to quench type as argued by the Appellants, would "improve the device characteristics" and "provide [a] better quality photodiode." 10 Finally, the Appellants argue that "[n]owhere in the application do we suggest using the device in a telecommunication application." Br. 21. Significantly, "the law does not require that the references be combined for the reasons contemplated by the inventor." In re Beattie, 974 F.2d 1309, 1312 (Fed. Cir. 1992). In sum, the Appellants have not demonstrated reversible error in the Examiner's findings of fact or conclusions of law in the rejection of claim 86. Therefore, the§ 103(a) rejection of claim 86 is sustained. 2. Claims 87 and 88 The Appellants argue that GaAs and GainP are "well known to exhibit poor avalanche photodiode characteristics." Br. 22, 23. Therefore, the Appellants argue "the Examiner is wrong in asserting that a person with ordinary skill in the art at 10 As discussed above, the Examiner finds Cova discloses a SPAD element integrated with a passive quench circuit. Ans. 6, 8. 6 Appeal2014-002628 Application 10/837,175 the time the invention was made would have a reason to believe that GaAs [and GainP] with a band gap above 1.42 eV [and a band gap above 1.9 eV, respectively] would improve the device characteristics." Br. 22, 23 (emphasis added). The Appellants' argument is not persuasive of reversible error. There is no dispute on this record that GaAs and GainP were known to be used in photodetectors at the time of the Appellants' invention. Thus, regardless of whether improved device characteristics would have been expected, the Examiner concludes that the mere substitution of materials would have been obvious to one of ordinary skill in the art. See KSR Int 'l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007) ("The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results."). The Appellants have failed to establish otherwise. The§ 103(a) rejection of claims 87 and 88 is sustained. 3. Claim 89 According to the Appellants, "[ t ]he Examiner is asserting that lower capacitance would naturally be desired to produce improved performance, yet he cites nothing in the prior art itself, or any logically reasoned argument, to explain why such would be the case." Br. 24. The Examiner finds the Appellants' argument misrepresents the Examiner's statement in the rejection of claim 89. We agree. See Ans. 15 ("The rejection recites that it would have been obvious to use capacitance less than 100 femtofarads in order to use the device in an application which requires specific capacitance."); see also Final 5. Moreover, in response to the Appellants' argument, the Examiner finds "[Cova's modified] device has a Geiger mode gain of less than 1,000,000 for said first SP AD element. In order to achieve Geiger mode gain of less than 1,000,000, 7 Appeal2014-002628 Application 10/837,175 the capacitance of said first SP AD element must inherently be less than 100 femtofarad. This assertion is supported by Bondarenko." Ans. 15 (citing Bondarenko, 187, col. 2). The Appellants have failed to establish otherwise. The§ 103(a) rejection of claim 89 is sustained. C. DECISION The Examiner's decision is affirmed. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a)(l). AFFIRMED 8 Copy with citationCopy as parenthetical citation