Ex Parte Ren et alDownload PDFPatent Trial and Appeal BoardDec 30, 201612714262 (P.T.A.B. Dec. 30, 2016) Copy Citation United States Patent and Trademark Office 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 APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 12/714,262 02/26/2010 Zaiyuan Ren 108298986US 6346 46844 7590 01/04/2017 PFRKTNS TOTF TIP- Mirrnn EXAMINER PATENT-SEA NADAV, ORI PO BOX 1247 SEATTLE, WA 98111 -1247 ART UNIT PAPER NUMBER 2811 NOTIFICATION DATE DELIVERY MODE 01/04/2017 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): patentprocurement @perkinscoie. com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte ZAIYUAN REN and THOMAS GEHRKE Appeal 2016-000130 Application 12/714,262 Technology Center 2800 Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and JAMES C. HOUSEL, Administrative Patent Judges. PER CURIAM. DECISION ON APPEAL1 STATEMENT OF THE CASE Appellants2 filed an appeal under 35 U.S.C. § 134 from the Examiner’s decision finally rejecting claims 1, 2, 4—7, 11—17, 20-24, 32, and 33. We have jurisdiction under 35 U.S.C. §§ 6(b) and 134(a). We REVERSE. 1 Our decision refers to Appellants’ Specification filed Feb. 26, 2010 (Spec.), the Final Office Action mailed Aug. 1, 2014 (Final Act.), Appellants’ Appeal Brief filed May 20, 2015 (Appeal Br.), the Examiner’s Answer mailed July 23, 2015 (Ans.), and Appellants’ Reply Brief filed Sept. 23,2015 (Reply Br.). 2 Appellants identify the real party in interest as Micron Technology, Inc. Appeal Br. 1. Appeal 2016-000130 Application 12/714,262 The claims on appeal are directed to methods of forming a light emitting diode (LED). See, e.g., Appeal Br. 20, 22, 24, 25—26 (claims 1,11, 20, 32, and 33). Appellants disclose that the wavelength of light emitted by an LED is at least partially related to the amount of indium in the InGaN material used in an LED. Spec. H 2, 3. A technique to enhance the incorporation of indium in the InGaN material is to form GaN/InGaN materials on nitrogen-polarity surfaces instead of on gallium-polarity surfaces via a process of nitrodizing a substrate. Spec. 14. A problem with this approach is that the nitrodizing product (e.g., silicon nitride) may interfere with subsequent deposition of GaN/InGaN materials. Spec. H 4, 25. To address this problem, Appellants disclose a method in which a nitrogen-rich environment causes nitrogen atoms to be loosely adsorbed on, diffused into, and/or otherwise attached to the surface of a silicon substrate without forming silicon nitride crystal structures. Spec. H 17, 18. Appellants believe the nitrogen-rich environment at the surface of the silicon wafer facilitates growth of GaN/InGaN materials with N-polarity instead of Ga-polarity. Spec. 124. Ga-polarity refers to a lattice structure extending along a direction with a Miller index of [0001] while a lattice structure with N-polarity extends along the opposite direction. Spec. 115. Independent claim 1 is illustrative of the subject matter on appeal. Claim 1 is reproduced from the Claims Appendix of the Appeal Brief with limitations at issue in the appeal italicized: 1. A method for forming a light emitting diode (LED), comprising: exposing a surface of a substrate to a nitrogen-containing composition, the substrate having a substrate material; 2 Appeal 2016-000130 Application 12/714,262 transferring nitrogen atoms from the nitrogen-containing composition to the substrate by adsorption onto the surface of the substrate, diffusion into the surface of the substrate, or both, at a temperature and/or energy level selected to prevent formation of a nitrodizing product of the substrate material; forming a nitrogen-polar material on the surface of the substrate after transferring the nitrogen atoms, wherein the nitrogen atoms at least partially cause the nitrogen-polar material to form with nitrogen polarity and wherein the nitrogen-polar material is N-type gallium nitride (GaN); and forming an LED structure by sequentially depositing the N-type gallium nitride, indium-gallium nitride (InGaN), and P- type GaN on the surface of the substrate, wherein the LED structure has an improved lattice quality relative to an LED structure with formation of a nitrodizing product of the susbtrate [sic] material. Appeal Br. 20. The claims on appeal stand rejected as follows: (1) claims 1, 2, 4—7, and 33 under 35 U.S.C. § 112, second paragraph, as being indefinite;3 (2) claims 1, 2, 4—7, 11—17, 20-24, and 33 under 35 U.S.C. § 103(a) as being unpatentable over Mashita4 in view of Applicants’ Admitted Prior Art5 and Krames6 or, alternatively, over Applicants’ 3 The Examiner has withdrawn the portion of the rejection directed to the language “at a temperature and/or energy level selected to prevent formation of a nitrodizing product of the substrate material” found in claims 1,11, and 20. Ans. 10. Thus, claims 11—17 and 20—24 are no longer subject to a rejection under 35 U.S.C. § 112, second paragraph. 4 Mashita, US 5,425,811, issued June 20, 1995 (“Mashita”). 5 The Examiner cites “figure 1 and related text” as Applicants’ Admitted Prior Art. Ans. 3. Figure 1A is labeled “Prior Art” and paragraphs 2-4 of the Specification comprise the “Background” section of the Specification. 6 Krames et al., US 8,334,155 B2, issued Dec. 18, 2012 (“Krames”). 3 Appeal 2016-000130 Application 12/714,262 Admitted Prior Art in view of Krames and Lee7 or Mashita;8 and (3) claims 2 and 32 under 35 U.S.C. § 103(a) as being unpatentable over Mashita in view of Applicants’ Admitted Prior Art, Krames, and Nishikawa9 or, alternatively, over Applicants’ Admitted Prior Art in view of Krames, Nishikawa, and Lee or Mashita. OPINION Indefiniteness Rejection Claims 1,2, 4—7, and 33 are rejected under 35 U.S.C. § 112, second paragraph, as being indefinite. The Examiner finds the language “forming a nitrogen-polar material on the surface of the substrate . . . and wherein the nitrogen-polar material is N-type gallium nitride (GaN); and forming an LED structure by sequentially depositing the N-type gallium nitride” in claims 1 and 33 is indefinite because the number of N-type gallium nitride layers being claimed is unclear. Final Act. 2—3. Appellants contend the language cited by the Examiner is not indefinite because one of ordinary skill in the art would recognize the language “N-type gallium nitride” refers to a type of material, not a particular quantity of material. Appeal Br. 10; Reply Br. 1—2. In order to determine if the claims set out and circumscribe a particular area with a reasonable degree of precision and particularity, we analyze the language of the claim “in light of the teachings of the prior art 7 Lee et al., US 7,497,963 B2, issued Mar. 3, 2009 (“Lee”). 8 The rejection of claims 1, 2, 4—7, 11—17, 20—24, and 33 under 35 U.S.C. § 103(a) as being unpatentable over Lee in view of Applicants’ Admitted Prior Art and Krames has also been withdrawn. Ans. 10. 9 Nishikawa et al., US 6,323,053 Bl, issued Nov. 27, 2001 (“Nishikawa”). 4 Appeal 2016-000130 Application 12/714,262 and of the particular application disclosure as it would be interpreted by one possessing the ordinary level of skill in the pertinent art.” In re Moore, 439 F.2d 1232, 1235 (CCPA 1971). We therefore turn to the Specification to analyze the meaning of the language cited by the Examiner. Paragraph 16 of the Specification describes an initial stage of a method to form an LED structure in which a nitrogen-rich environment is generated at least proximate to a surface of a substrate without forming a nitride material on the substrate surface. As described in paragraph 17 of the Specification, the nitrogen atoms may be loosely adsorbed on, diffused into, and/or otherwise attached to the substrate surface. Once the nitrogen-rich environment has been generated, the method includes steps to form an LED structure on the substrate. Spec. 121. A first step of forming an LED structure includes depositing a first semiconductor material, such as an N- type gallium nitride material, on the substrate having the nitrogen-rich environment. Spec. 121. Appellants state a belief in paragraph 24 of the Specification that the nitrogen-rich environment at the surface of the substrate can facilitate growth of the gallium nitride material with N- polarity. Therefore, the Specification describes a method in which nitrogen atoms are transferred to a surface of a substrate, such as via adsorption and/or diffusion of the nitrogen atoms, while preventing formation of a nitrodizing product so a N-polar semiconductor material, such as N-type gallium nitride having N-polarity, may be formed on the substrate. The Specification describes further steps for forming an LED structure, including the formation of an active region, such as by growing an InGaN material, on the first semiconductor material and forming a second semiconductor material, such as p-type GaN, on the active region. Spec. 5 Appeal 2016-000130 Application 12/714,262 H 21—23. Therefore, the Specification describes formation of the InGaN and p-type GaN materials on the N-type GaN material having a N-polarity. In light of the description provided by Appellants’ Specification, one of ordinary skill in the art would understand the N-type gallium nitride referenced in the language “forming an LED structure by sequentially depositing the N-type gallium nitride” to refer to the N-type gallium nitride produced by the step of “forming a nitrogen-polar material on the surface of the substrate after transferring the nitrogen atoms.”10 Therefore, the step of “forming an LED structure” in claims 1 and 33 includes the N-type GaN material having N-polarity and depositing two additional materials: InGaN and p-type GaN. Although the claims could have been more precisely drafted,* 11 claims 1 and 33 set out and circumscribe methods for forming a light emitting diode with a reasonable degree of precision and particularity for the purposes of § 112, second paragraph. In view of the above, we do not sustain the Examiner’s rejection of claims 1, 2, 4—7, and 33 under 35 U.S.C. § 112, second paragraph, as being indefinite. 10 The use of “the” to provide antecedent basis, must be read to refer to the N-type gallium nitride already deposited by the “forming a nitrogen-polar material.” 11 For instance, the claims would be clearer if the step of forming the LED structure where changed to more precisely use antecedent basis by, for instance, rewording the step to read: “sequentially depositing indium- gallium nitride (InGaN) and P-type GaN on the nitrogen-polar material to form an LED structure.” The Examiner is free to suggest such antecedent basis corrections. MPEP § 2173.05(e)(1). 6 Appeal 2016-000130 Application 12/714,262 Obviousness Rejection of Claims 1, 2, 4—7, 11—17, 20—24, and 33 Claims 1, 2, 4—7, 11—17, 20—24, and 33 are rejected under 35 U.S.C. § 103(a) as being unpatentable over Mashita in view of Applicants’ Admitted Prior Art and Krames or, alternatively, over Applicants’ Admitted Prior Art in view of Krames and Lee or Mashita. Appellants do not argue claims 2, 4—7, 11—17, 20-24, and 33 separately from claim 1. Appeal Br. 10—18. Therefore, we select claim 1 as representative of the issues on appeal. The dispositive issue on appeal is whether the Examiner has articulated a reason for one of ordinary skill in the art to have combined the teachings of the applied references such that the ordinary artisan would have been led to the claimed invention. Mashita discloses a method of depositing a nitrogen-containing compound thin film on a substrate by incorporating nitrogen into a compound thin film during growth. Mashita, col. 1,11. 8—12, 46—54. Specifically, Mashita discloses growing ZnSe on a substrate surface by using a Zn vapor source and a Se vapor source. Mashita col. 5,11. 57—60. A nitrogen beam source is also driven to adsorb nitrogen excitation species on the surface of the substrate, “thereby preferentially forming Zn—N bonds,” so the nitrogen is ultimately doped into the ZnSe material. Mashita, col. 5,1. 60 to col. 6,1. 15. Appellants’ Background section of the Specification, which the Examiner relies upon as “Applicants]’ Admitted Prior Art,” describes a conventional light emitting diode including a substrate, an optional buffer material, an N-type gallium nitride material, an InGaN material, and a P- type GaN material. Spec. 12. According to the Background section, it is 7 Appeal 2016-000130 Application 12/714,262 believed that the wavelength emitted by the LED is at least partially related to the amount of indium (In) in the InGaN material. Spec. 13. One technique for enhancing the incorporation of indium in the InGaN material is to form the GaN/InGaN materials on nitrogen-polarity surfaces rather than on gallium-polarity surfaces via nitrodizing the substrate. Spec. 14. The Background section expresses a problem with this technique. Nitrodizing the substrate may interfere with subsequent deposition of GaN/InGaN materials. Spec. 14. Krames discloses growth substrates on which light emitting diodes may be grown. Krames, col. 1,11. 7—10. The substrate includes a host and a seed layer bonded to the host upon which a semiconductor structure is grown, wherein the semiconductor structure includes a light emitting layer between an n-type region and a p-type region. Krames, col. 1,11. 57—61. Krames further discloses that Ill-nitride seed layers grown on sapphire or silicon carbide are typically grown as c-plane wurtzite, which have gallium- polarity and nitrogen polarity. Krames, col. 9,11. 10-17. Because the nitrogen-polarity surface is typically the bottom surface of the nitride, one can grow a seed layer on sapphire or silicon carbide, connect the seed layer to a host, and remove the growth substrate to expose the nitrogen-polarity surface of the Ill-nitride seed layer. Krames, col. 9,11. 17—25. However, because Ill-nitrides preferentially grow on the gallium-polarity surface, growth on the nitrogen-polarity surface “may undesirably introduce defects into the crystal, or result in poor quality material.” Krames, col. 9,11. 25—32. In view of this, Krames discloses growing a composite substrate with a III- nitride seed layer having gallium-polarity, not nitrogen-polarity, as the top surface upon which epitaxial growth is conducted. Krames, col. 9,11. 33—49. 8 Appeal 2016-000130 Application 12/714,262 Lee discloses a dry etching method that can be used to etch a silicon oxide film on a silicon substrate. Lee, col. 1,11. 6—7; col. 3,11. 34—36. Lee discloses using nitrogen trifluoride gas as an etching gas, which is adsorbed on the surface of the silicon substrate. Lee, col. 3,11. 36—38. Subsequently, free radicals of hydrogen gas react with the nitrogen trifluoride gas adsorbed on the substrate surface to produce an intermediate product, which in turn reacts with the silicon oxide on the substrate to produce a reaction product that can be thermally decomposed and evaporated to selectively etch the silicon oxide. Lee, col. 3,11. 39-64. In the Answer, the Examiner finds Mashita discloses the formation of a nitrogen-polarity surface on a substrate via adsorption or diffusion without the formation of a nitrodizing product. Ans. 3, 4, 6, 17, 18. The Examiner does not provide any citations to Mashita to support this finding. As noted above, Mashita discloses the adsorption of nitrogen excitation species on the surface of a substrate, “thereby preferentially forming Zn—N bonds,” to dope the nitrogen a ZnSe material. Therefore, any adsorption of nitrogen on the surface of a substrate in the method of Mashita is for the subsequent formation of a ZnSe material, wherein Zn-N bonds are preferentially formed in the process, which indicates the formation of a nitride. The Examiner finds the Applicants’ Admitted Prior Art discloses the difficulty of using a nitrodized substrate to provide a nitrogen-polarity surface for subsequent deformation of GaN/InGaN materials. Ans. 17—18. Based on this, the Examiner finds “said nitrogen-polarity surfaces should be formed without producing the interfering nitrodizing product.” Ans. 18 (emphasis omitted). 9 Appeal 2016-000130 Application 12/714,262 The Examiner explains the phenomenon of transferring nitrogen to a substrate surface is well-known in the art and is accomplished via weak interactions, such as via adsorption or diffusion, or strong interactions, such as via ionic or covalent bonds. Ans. 18. The Examiner finds “weak interactions do not result in the formation of a nitrodizing product” and “[bjased on the above physical phenomenon, it is clear that in order to form nitrogen-polarity surfaces without producing a nitrodizing product, the nitrogen must be attached to the substrate by using weak interactions such as adsorption or diffusion.” Ans. 18. However, the Examiner does not provide any citations to the prior art to support these findings. The Examiner further finds Krames discloses the formation of a nitrogen-polarity surface. Ans. 3, 4, 19-20. With regard to Lee, the Examiner finds Lee discloses forming a nitrogen-rich portion of a substrate while preventing the formation of a nitrodizing product. Ans. 5. The Examiner concludes it would have been obvious to modify the process of Mashita in view of the Applicants’ Admitted Prior Art and Krames to form an LED structure on the substrate disclosed by Mashita. Ans. 3, 4, 18—19. For the alternative rejection, the Examiner concludes it would have been obvious to form a nitrogen-rich portion of a substrate without forming a nitrodizing product (citing Lee, Mashita, and Krames) to form the LED structure of the Applicants’ Admitted Prior Art. Ans. 5—6. Appellants contend there would have been a lack of reason to combine the applied references. Appeal Br. 13—16; Reply Br. 2—6. Appellants’ arguments are persuasive. “[Rejections on obviousness grounds cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to 10 Appeal 2016-000130 Application 12/714,262 support the legal conclusion of obviousness.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007) (quoting In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006). Here, the Examiner’s rejection rests upon statements regarding the preference for a particular type of interaction (i.e., adsorption or diffusion) between nitrogen atoms and a substrate surface to form a nitrogen-rich environment on a substrate without forming a nitrodizing product so a nitrogen-polar material can be formed on the substrate surface. Ans. 18. These statements are conclusory and lack citations to the record for support. Instead, the Examiner has engaged in impermissible hindsight in the rejection of claim 1. Any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning, but so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made and does not include knowledge gleaned only from applicant’s disclosure, such a reconstruction is proper. In re McLaughlin, 443 F.2d 1392, 1395 (CCPA 1971). However, a fact finder must be aware “of the distortion caused by hindsight bias and must be cautious of arguments reliant upon ex post reasoning.” KSR Int’l Co., 550 U.S. at 421 (2007) (citing Graham v. John Deere Co., 383 U.S. 1, 36 (1966) (warning against a “temptation to read into the prior art the teachings of the invention in issue”)). Therefore, we do not sustain the § 103(a) rejection of claims 1,2, 4—7, 11-17,20-24, and 33.12 12 At page 23 of the Answer, the Examiner indicates Appellants have not traversed the alternative rejection over the Applicants’ Admitted Prior Art in view of Krames and Lee or Mashita. Although Appellants did not specifically address each rejection individually in the Appeal Brief, which was filed prior to the first part of the rejection being altered in the Answer, 11 Appeal 2016-000130 Application 12/714,262 Obviousness Rejection of Claims 2 and 32 Claims 2 and 32 are rejected under 35 U.S.C. § 103(a) as being unpatentable over Mashita in view of Applicants’ Admitted Prior Art, Krames, and Nishikawa or, alternatively, over Applicants’ Admitted Prior Art in view of Krames, Nishikawa, and Lee or Mashita. The rejection of claims 2 and 32 includes Mashita, the Applicants’ Admitted Prior Art, Krames, and Lee, therefore, has the same deficiencies as the § 103 rejection of claims 1, 2, 4—7, 11—17, 20—24, and 33. Moreover, the Examiner does not rely upon Nishikawa to remedy the deficiencies of the rejection of claims 1, 2, 4—7, 11—17, 20—24, and 33. Therefore, we do not sustain the Examiner’s § 103(a) rejection of claims 2 and 32. DECISION The Examiner’s decision is reversed. REVERSED Appellants addressed each reference and whether one of ordinary skill in the art would have had a reason to combine the references. Appellants identified a reversible error that applies to the alternative reasoning as well as the primary basis for rejection. 12 Copy with citationCopy as parenthetical citation