Ex Parte Houston et alDownload PDFPatent Trials and Appeals BoardMay 10, 201613478839 - (D) (P.T.A.B. May. 10, 2016) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 13/478,839 05/23/2012 23494 7590 05/12/2016 TEXAS INSTRUMENTS IN CORPORA TED P 0 BOX 655474, MIS 3999 DALLAS, TX 75265 FIRST NAMED INVENTOR Theodore W. Houston 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. TI-36169.2 1045 EXAMINER DIAZ,JOSER ART UNIT PAPER NUMBER 2815 NOTIFICATION DATE DELIVERY MODE 05/12/2016 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): uspto@ti.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte THEODORE W. HOUSTON, SHYH-HORNG YANG, and KAYVANSADRA Appeal2015-000332 Application 13/478,839 Technology Center 2800 Before JESSICA C. KAISER, SHARON PENICK, and JOHN R. KENNY, Administrative Patent Judges. KAISER, Administrative Patent Judge. DECISION ON APPEAL Appellants 1 appeal under 35 U.S.C. § 134(a) from the Examiner's final rejection of claims 1--4, all of the claims pending in this application. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. 1 According to Appellants, the real party in interest is Texas Instruments Incorporated. (Br. 3.) Appeal2015-000332 Application 13/478,839 EXEMPLARY CLAIM Claim 1 is exemplary and is reproduced below: 1. An SRAM memory cell, comprising: a storage node of the SRAM memory cell; a bitline node of the SRAM memory cell; and an asymmetrical access transistor connected between the storage node and bitline node of the SRAM memory cell, wherein the asymmetrical access transistor has a first threshold voltage when said storage node is positive with respect to the bitline node and said asymmetrical access transistor has a second threshold voltage of greater magnitude than the first threshold voltage when the storage node is negative with respect to the bitline node. REJECTION The Examiner has rejected claims 1--4 under 35 U.S.C. § 103(a) as being unpatentable over Lien (US 5, 790,452; issued Aug. 4, 1998) and \Vang (US 6,566,204 Bl; issued ~v1ay 20, 2003). (Final Act. 2-5.) ANALYSIS We have reviewed the Examiner's rejections in light of Appellants' arguments that the Examiner has erred. We disagree with Appellants' conclusions. In so far as they relate to issues raised in this appeal, we adopt as our own the findings and reasons set forth by the Examiner in the Final Action from which the appeal is taken and the reasons set forth in the Examiner's Answer in response to Appellants' Appeal Brief (see Ans. 5- 12). We highlight and address specific findings and arguments for emphasis as follows. 2 Appeal2015-000332 Application 13/478,839 Claim 1 Appellants argue the Examiner errs in finding Lien or Wang teaches "an asymmetrical access transistor having a first threshold voltage when the storage node is positive with respect to the bitline node and a second threshold voltage of greater magnitude than the first threshold voltage when the storage node is negative with respect to the bitline node," as recited in claim 1. (Br. 7-8.) We are not persuaded of Examiner error. The Examiner finds, and we agree, that Lien teaches the asymmetrical access transistor recited in claim 1. (Ans. 7 (citing Lien Fig. 3, 4:22-30).) Figure 3 of Lien is reproduced below. 11 ' "'"""'""""-----t""""""""'"''"""'·--------------- \ 1 Figure 3 depicts a cross-sectional view of asymmetrical transistor 202. Lien teaches that region 3 is connected to the bitline, and region 2/4 is connected to the storage node. (Lien 4:33-36, Fig. 2.) Lien further teaches that asymmetrical transistor 202 has a threshold voltage of 0.5 volts when region 4 is biased as the source of the transistor (i.e., when the storage node is positive with respect to the bitline node), and has a threshold voltage of 0. 7 3 Appeal2015-000332 Application 13/478,839 volts when region 3 is biased as the source of the transistor (i.e., when the storage node is negative with respect to the bitline node). (Id. at 4:22-36, Fig. 3.) Therefore, we agree with the Examiner (Ans. 7) that Lien teaches an asymmetrical access transistor having "a first threshold voltage when the storage node is positive with respect to the bitline node" (i.e., 0.5 volts when the storage node is biased as the source) and "a second threshold voltage of greater magnitude than the first threshold voltage when the storage node is negative with respect to the bitline node" (i.e., 0.7 volts when the bitline is biased as the source). Appellants have not persuasively responded to the Examiner's findings regarding these teachings in Lien. (See Br. 7-8.) Appellants further argue that Wang and Lien teach away "by teaching the opposite halo structure," and that Wang teaches away because its device has a permanent source and drain. (Br. 8-10.) We disagree. To teach away, a reference must actually "criticize, discredit, or otherwise discourage" investigation into the claimed solution. In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004). We observe that claim 1 does not require any particular halo (or pocket implant) region. Thus, Appellants' alleged teaching away based on halo structure is not commensurate in scope with claim 1. In addition, Appellants have not persuasively shown that merely describing one type of halo structure or device configuration criticizes, discredits, or discourages investigation into any other type of halo structure or device configuration. Appellants argue Lien is not analogous art. 2 (Br. 10.) The Examiner finds Lien is analogous art because it is in the same field of endeavor as 2 To the extent Appellants intended to argue Wang is not analogous art, we are unpersuaded for similar reasons. 4 Appeal2015-000332 Application 13/478,839 Appellants' invention. (Final Act. 4; see also Ans. 9-10.) We agree with the Examiner and also observe that Appellants' Specification expressly discusses Lien and Wang and incorporates both by reference. (Spec. i-fi-1 5- 8.) Appellants argue "a person of ordinary skill in the art would not combine a unidirectional transistor (Wang et al.) with a bidirectional transistor ([Lien])." (Br. 10.) In support, Appellants argue only that "[t]he IGFET [('insulated-gate field-effect transistor')] taught by Wang et al. cannot operate as a pass transistor." (Id.) The test for obviousness, however, "is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference." In re Keller, 642 F.2d 413, 425 (CCPA 1981). Rather, "if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill." KSR Int'! Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007). Appellants' argument is unpersuasive because the Examiner does not rely on a bodily incorporation of Wang's transistor in Lien, but rather "modifying the pocke[t] region of Lien in view of Wang." (Ans. 10.) For the reasons discussed above, we sustain the Examiner's§ 103 rejection of claim 1. Claims 2--4 Claims 2--4 depend directly or indirectly from claim 1 and are reproduced below. 5 Appeal2015-000332 Application 13/478,839 2. The SRAM memory cell of claim 1, wherein a difference between said second threshold voltage and said first threshold voltage is approximately 1 OOm V. 3. The SRAM memory cell of claim 1, wherein the asymmetrical access transistor includes a pocket implant region on a storage node side. 4. The SRAM memory cell of claim 3, wherein said asymmetrical access transistor comprises a source region and a drain region of a first conductivity type and wherein said pocket implant region is of a second conductivity type, opposite said first conductivity type. Regarding claim 2, Appellants argue "[Lien] teaches away from the advantageously claimed invention by teaching that the difference between the forward threshold voltage and the reverse threshold voltage is [OJ .2 volts." (Br. 12 (citing Lien 4:22-32).) We disagree because Appellants have not shown that disclosing a certain voltage difference teaches away from other voltage differences. In addition, the Examiner finds that discovering the optimum range (e.g., 100 m V) would have involved only routine skill. (Ans. 10-11; Final Act. 5.) Appellants have not persuasively responded to this finding. Regarding claim 3, Appellants argue that Lien teaches away "by teaching that the pocket implant is on the bit line side." (Br. 13 (citing Lien 4:33-34, 38-39).) As discussed above, Appellants have not shown that Lien teaches away. Appellants further argue that Wang "cannot teach a pocket implant region on a storage node side because the IGFET of Wang et al. is a unidirectional transistor (whereas, a transistor having a 'storage node side' must be a bidirectional transistor)." (Id.) We find this argument unpersuasive because it addresses Wang individually. Keller, 642 F.2d at 6 Appeal2015-000332 Application 13/478,839 426 ("[O]ne cannot show non-obviousness by attacking references individually where ... the rejections are based on combinations of references.") (citation omitted). The Examiner finds that Lien (not Wang) teaches the recited access transistor, and the Examiner relied on Wang as teaching "the shape of [Wang's] pocket region (108) [was] known in the art and that changing the shape of the pocket region in Lien yields nothing more than predictable results to one of ordinary skill in the art." (Ans. 7-8, 11.) Appellants' arguments do not persuasively address these findings. Appellants' arguments regarding claim 4 are substantially similar to their arguments regarding claim 3 (Br. 13-15), and we find them unpersuasive for the reasons discussed above. In addition, we agree with the Examiner's finding that Lien teaches "a source region and a drain region of a first conductivity type" (i.e., in Lien Figure 3, regions 2/4 and 3 are N-type) and "wherein said pocket implant region is of a second conductivity type, opposite said first conductivity type" (i.e., in Lien Figure 3, pocket region 5 is P-type ). (Ans. 12.) Appellants' arguments do not persuasively address this teaching or the Examiner's combination of Lien's and Wang's teachings (Final Act. 4--5). For the reasons discussed above, we sustain the Examiner's§ 103 rejections of claims 2--4. DECISION We affirm the Examiner's decision to reject claims 1--4 under 35 U.S.C. § 103(a). 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 )(iv). 7 Appeal2015-000332 Application 13/478,839 AFFIRMED 8 Copy with citationCopy as parenthetical citation