Texas Instruments Incorporated

Patent Trials and Appeals BoardDec 10, 2021

2021002428 (P.T.A.B. Dec. 10, 2021)

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. 16/169,843 10/24/2018 Dibyajat Mishra TI-78261 3665 23494 7590 12/10/2021 TEXAS INSTRUMENTS INCORPORATED P O BOX 655474, MS 3999 DALLAS, TX 75265 EXAMINER NGUYEN, SOPHIA T ART UNIT PAPER NUMBER 2822 NOTIFICATION DATE DELIVERY MODE 12/10/2021 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 DIBYAJAT MISHRA, VIVEK ARORA, ASHOK PRABHU, and KEN PHAM Appeal 2021-002428 Application 16/169,843 Technology Center 2800 Before JEAN R. HOMERE, MINN CHUNG, and AMBER L. HAGY, Administrative Patent Judges. HAGY, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1–23, which are all of the pending claims. Appeal Br. 15–19 (Claims App.) We have jurisdiction under 35 U.S.C. § 6(b). We affirm. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as Texas Instruments Incorporated. Appeal Br. 3. Appeal 2021-002428 Application 16/169,843 2 CLAIMED SUBJECT MATTER Appellant’s disclosure is directed “generally to electronic circuitry, and more particularly to isolation of electronic devices on a substrate.” Spec. ¶ 1. Claims 1, 10, 17, and 21 and are independent. Claim 1, reproduced below, is illustrative of the claimed subject matter: 1. An apparatus comprising: a substrate comprising: a first surface and an opposing second surface; a trench extending into the substrate from the first surface; a die mounting area adjacent to the trench; a first plurality of leads; a second plurality of leads, wherein the second plurality of leads are spaced from the trench to electrically isolate the second plurality of leads; a first mold compound filling the trench to form a filled trench; a first die attached to the first surface of the substrate in the die mounting area, and electrically connected to at least one of the first plurality of leads; and a second die attached to a surface of the first mold compound in the filled trench, wherein the first mold compound completely covers a bottom surface of the second die. Appeal Br. 15 (Claims App.). Appeal 2021-002428 Application 16/169,843 3 REFERENCES The prior art relied upon by the Examiner is: Name2 Reference Date Jeon US 2007/0001278 A1 Jan. 4, 2007 Tateishi US 8,299,588 B1 Oct. 30, 2012 Williams US 2014/0306330 A1 Oct. 16, 2014 How US 2016/0071743 A1 Mar. 10, 2016 Danno US 9,735,127 B2 Aug. 15, 2017 Huang US 9,799,613 B1 Oct. 24, 2017 REJECTIONS Claims 1–6 stand rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, and Jeon. Final Act. 2–7. Claim 7 stands rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, Jeon, and Tateishi. Final Act. 8–9. Claims 8 and 9 stand rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, Jeon, and Danno. Final Act. 9–11. Claims 10, 11, 13, 14, and 17–23 stand rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, and Jeon, and Danno. Final Act. 11–27. Claim 12 stands rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, Jeon, Danno, and Williams. Final Act. 27–28. Claims 15 and 16 stand rejected under 35 U.S.C. § 103 as obvious over the combined teachings of How, Huang, Jeon, Danno, and Tateishi. Final Act. 28–30. 2 All references herein are identified by the first-named inventor. Appeal 2021-002428 Application 16/169,843 4 OPINION We have reviewed the Examiner’s rejections in light of Appellant’s arguments the Examiner has erred. Appellant’s arguments do not persuade us of Examiner error. We adopt as our own: (1) the findings and reasons set forth by the Examiner in the action from which this appeal is taken (Final Act. 3–30) and (2) the reasons set forth by the Examiner in the Examiner’s Answer in response to Appellant’s Appeal Brief (Ans. 4–7). We concur with the conclusions reached by the Examiner, and we highlight the following for emphasis.3 The Examiner finds How teaches most of the limitations of claim 1,4 including a trench extending into the substrate, but finds How does not disclose the limitations reciting a mold compound filling the trench. Final Act. 2–3. For those limitations, the Examiner relies on Huang and Jeon in combination with How. Id. at 4–5 (citing Huang, Figs. 4, 10, 2:1–30, 4:9– 18, 5:10–39, claims 1, 5; Jeon ¶¶ 333–335, Fig. 25). The Examiner also finds How discloses that the number of channels can be reduced “by forming a sufficiently large channel.” Id. at 4 (citing How ¶ 21) (emphasis omitted). The Examiner further finds: 3 Only those arguments made by Appellant have been considered in this decision. Arguments Appellant did not make are deemed to be waived. See 37 C.F.R. § 41.37(c)(1)(iv). 4 Appellant does not present separate, substantive, persuasive arguments with respect to independent claims 10, 17, or 21, but repeats the same or similar arguments already raised with respect to claim 1. See Appeal Br. 10–13. Appellant argues the dependent claims collectively with their respective independent claims. See id. at 6–13. Therefore, we select claim 1 as the representative claim, pursuant to our authority under 37 C.F.R. § 41.37(c)(1)(iv). Claims 2–23 stand or fall with claim 1. Appeal 2021-002428 Application 16/169,843 5 Thus, it would be obvious to one of ordinary skill in the art to form a single channel that has a width greater than a width of the second die to alleviate the problems of electrical leakage failure between the controller die and the die attach paddle due to silicon splinters in the die attach film and/or due to a central hole in the die attach film produced by a die ejector pin. In a case when a single channel having a width greater than a width of the second die, filling the trench with the first mold compound as suggested by Huang et al. and/or Jeon would result to “wherein the first mold compound completely covers a bottom surface of the second die.” Id. at 5. Appellant argues that the Examiner’s findings are in error because How fails to teach or suggest “wherein the first mold compound completely covers a bottom surface of the second die,” and asserts that if How’s channels 64 and 74 are made bigger to cover the bottom side of the die, then “the die will be proximate the die paddle 14, which is exactly the situation How tries to avoid.” Appeal Br. 6–7. We are not persuaded of Examiner error in the rejection. Although we agree with Appellant that How discloses channels under the die to solve a problem of avoiding electrical shorts between the die and the die paddle (see Appeal Br. 6), we disagree with Appellant that increasing the channels in How to create a trench larger than the die would result in the die being proximate the die paddle (see id. at 7). Appellant’s argument in this regard fails to account for the Examiner’s finding that How’s channels would be filled with a nonconductive material, according to the teachings of Huang and Jeon combined with How. See Ans. 5–6. In particular, the Examiner finds: [N]ot only How but also Joen discloses a way to avoid electrical shorts between the die and the die paddle. Fig. 25 and Appeal 2021-002428 Application 16/169,843 6 paragraph [0333] of Jeon discloses that short circuit between the die [604] and the paddle [610] or between the die [604] and dies [602 or 606] is prevented due to the filled recess [690 and 692] . . . . Therefore, replacing [the plurality of] trenches of How with a single filled trench of Jeon would not change the intended operation of Jeon’s device. Ans. 5. In the Reply Brief, Appellant again contends that increasing How’s channels to make them bigger would increase the proximity between How’s die and the die attach paddle. Reply Br. 2. As noted, this argument does not persuasively address the Examiner’s contrary findings that How’s enlarged channel would be filled with a nonconductive material, according to the teachings of Huang and Jeon, and thus How’s die would remain electrically isolated from the die paddle. See Ans. 5. For the foregoing reasons, we are not persuaded of Examiner error in the rejection of claim 1 or of claims 2–23, argued on the same basis as claim 1. We, therefore, sustain the Examiner’s rejections on this record. CONCLUSION The Examiner’s 35 U.S.C. § 103 rejections of claims 1–23 are sustained. Appeal 2021-002428 Application 16/169,843 7 DECISION SUMMARY In summary: Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1–6 103 How, Huang, Jeon 1–6 7 103 How, Huang, Jeon, Tateishi 7 8, 9 103 How, Huang, Jeon, Danno 8, 9 10, 11, 13, 14, 17–23 103 How, Huang, Jeon, Danno 10, 11, 13, 14, 17–23 12 103 How, Huang, Jeon, Danno, Williams 12 15, 16 103 How, Huang, Jeon, Danno, Tateishi 15, 16 Overall Outcome 1–23 TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv) (2020). AFFIRMED