Micron Technology, Inc.Download PDFPatent Trials and Appeals BoardMay 29, 202014743124 - (D) (P.T.A.B. May. 29, 2020) 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. 14/743,124 06/18/2015 Eric Tan Swee Seng 2269-6331.4(2003-1364.04) 8349 63162 7590 05/29/2020 TRASK BRITT, P.C./ MICRON TECHNOLOGY P.O. BOX 2550 SALT LAKE CITY, UT 84110 EXAMINER PIZARRO CRESPO, MARCOS D ART UNIT PAPER NUMBER 2814 NOTIFICATION DATE DELIVERY MODE 05/29/2020 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): USPTOMail@traskbritt.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte ERIC TAN SWEE SENG ____________ Appeal 2019-004539 Application 14/743,124 Technology Center 2800 ____________ Before ROMULO H. DELMENDO, JEFFREY T. SMITH, and DEBRA L. DENNETT, Administrative Patent Judges. DENNETT, Administrative Patent Judge. DECISION ON APPEAL1 STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the Examiner’s decision to reject claims 1, 4–6, 10–14, 16–18, and 20 of Application 14/743,124.3 We have jurisdiction under 35 U.S.C. § 6(b). 1 In our Decision, we refer to the Specification (“Spec.”) of Application No. 14/743,124 filed June 18, 2015 (’124 App.”); the Final Office Action dated May 18, 2018 (“Final Act.”); the Appeal Brief filed Nov. 26, 2018 (“Appeal Br.”); the Examiner’s Answer dated Mar. 22, 2019 (“Ans.”); and the Reply Brief filed May 21, 2019 (“Reply Br.”). 2 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies the real party in interest as MICRON TECHNOLOGY, INC. Appeal Br. 2. 3 Claims 2 and 3 have been withdrawn from consideration. Final Act. 1. Appeal 2019-004539 Application 14/743,124 2 For the reasons set forth below, we AFFIRM. The subject matter of the invention relates to multi-chip modules in which two or more semiconductor devices are stacked relative to one another. Spec. ¶ 2. In particular, distances between adjacent, stacked semiconductor devices are determined, at least in part, by a plurality of discrete spacers interposed therebetween, and discrete conductive elements protrude from a central region of the lower semiconductor device and pass through a common aperture formed between the active surface of the lower semiconductor device, the back side of the upper semiconductor device and two of the spacers. Spec. ¶ 2. Claim 1, reproduced below from the Claims Appendix of the Appeal Brief, illustrates the claimed subject matter: 1. A multi-chip module on a substrate having contact areas on a surface thereof, comprising: a first semiconductor device having an active surface including bond pads thereon and an opposing back side affixed to the substrate; a second semiconductor device having a back side stacked over the first semiconductor device; spacers interposed between the active surface of the first semiconductor device and the back side of the second semiconductor device; a first opening facing a first periphery of the stacked first and second semiconductor devices and defined between a first set of spacers of the spacers, the first semiconductor device, and the second semiconductor device; a second opening facing a second, opposing periphery of the stacked first and second semiconductor devices and defined between a second set of spacers of the spacers, the second, opposing periphery of the stacked first and second semiconductor devices opposing the first periphery of the stacked first and second semiconductor devices, the first Appeal 2019-004539 Application 14/743,124 3 semiconductor device, and the second semiconductor device, wherein the first set of spacers is separate from the second set of spacers; a third opening facing a third periphery of the stacked first and second semiconductor devices and defined between a third set of spacers of the spacers, the first semiconductor device and the second semiconductor device, wherein the third periphery of the stacked first semiconductor device and the second semiconductor device is oriented in a direction transverse to the first periphery and the second periphery; discrete conductive elements, each extending over the active surface of the first semiconductor device from respective bond pads of the bond pads positioned at an interior portion of the active surface of the first semiconductor device to respective contact areas on the substrate surface between at least two of the first opening, the second opening, and the third opening, wherein at least the first opening and the third opening have at least one of the discrete conductive elements extending therethrough, and wherein at least one of the first set of the spacers, the second set of the spacers, and the third set of the spacers are positioned at an outer portion of the active surface of the first semiconductor device proximate an outer boundary of the active surface; a dielectric coating on at least portions of at least one of the discrete conductive elements and the back side of the second semiconductor device, the dielectric coating configured to electrically isolate the discrete conductive elements from the back side of the second semiconductor device; and an insulative material disposed at least partially between the first semiconductor device and the second semiconductor device. Appeal Br. 24–25 (Claims App.) (some formatting added). Appeal 2019-004539 Application 14/743,124 4 REFERENCES The Examiner relies on the following prior art in rejecting the claims: Name Reference Date LoBianco et al. (“LoBianco”) US 6,340,846 B1 Jan. 22, 2002 Akram et al. (“Akram”) US 2002/0043711 A1 Apr. 18, 2002 Derderian US 2003/0038355 A1 Feb. 27, 2003 Kurita et al. (“Kurita”) US 2003/0189259 A1 Oct. 9, 2003 REJECTIONS The Examiner maintains the following rejections under 35 U.S.C. § 103(a): A. Claims 1, 5, 6, and 10–12 over LoBianco in view of Derderian; B. Claim 13 over Kurita in view of Derderian; C. Claims 16–18 and 20 over LoBianco in view of Kurita; D. Claim 4 over LoBianco and Derderian in view of Akram; and E. Claim 14 over Kurita and Derderian in view of Akram. Final Act. 3–9. DISCUSSION We review the appealed rejections for error based upon the issues identified by Appellant and in light of the arguments and evidence produced thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential), (cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)) (“[I]t has long been the Board’s practice to require an applicant to identify the alleged error in the [E]xaminer’s rejections.”). After considering the evidence presented in this Appeal and each of Appellant’s arguments, we are not persuaded that Appellant identifies reversible error in the Examiner’s rejections. Appeal 2019-004539 Application 14/743,124 5 A. Rejection of claims 1, 5, 6, and 10–12 as obvious over LoBianco in view of Derderian Appellant argues claims 1, 5, 6, and 10–12 as a group. See Appeal Br. 14–16. We select independent claim 1 as representative of the group. 37 C.F.R. § 41.37(c)(1)(iv). Claims 5, 6, and 10–12 stand or fall with claim 1. The Examiner finds that LoBianco teaches most aspects of claim 1, but does not teach (1) a first, second, and third set of spacers interposed between the first and second devices to define the openings, wherein at least a set of the spacers is positioned at an outer portion of the first device proximate to an outer boundary of the active surface, or (2) a dielectric coating on at least portions of one of the conductive elements and the back side of the second device, wherein the coating is configured to electrically isolate the conductive elements from the back side of the second device. Final Act. 3–4. The Examiner finds that Derderian teaches such spacers and a dielectric coating on at least portions of the conductive elements and back side of the second device. Id. at 4. The Examiner determines that it would have been obvious to one of ordinary skill in the art at the time of the invention to include the dielectric coating and the spacers of Derderian in LoBianco’s4 module to prevent shorting and protect the conductive elements. Id. (citing Derderian ¶¶ 60, 61). The Examiner bases the rejection on an embodiment (illustrated in LoBianco Fig. 6) that does not include spacers. Ans. 12. In response to 4 In stating a conclusion of obviousness, the Final Office Action refers incorrectly to the module of Kurita, rather than the module of LoBianco. Final Act. 12. It is clear from the Appeal Brief that Appellant understood the rejection to be over LoBianco in view of Derderian (see Appeal Br. 14– 16), and thus we determine the error is harmless. Appeal 2019-004539 Application 14/743,124 6 Appellant’s argument that LoBianco discloses spacers in the form of microspheres in an different embodiment (illustrated in LoBianco Fig. 7) (Appeal Br. 15), the Examiner finds that design incentives would have motivated one of ordinary skill in the art to look at other kinds of spacers to implement a predictable variation. Ans. 12. The Examiner finds that Derderian’s spacers would provide additional positive results, including defining openings used to receive LoBianco’s adhesive layer laterally and reducing or eliminating the incidence of bubble formation in the adhesive. Id. at 12–13 (citing Derderian ¶¶ 46, 47). With regard to prevention of shorting as a reason to combine the references, the Examiner concludes that finding one solution to a problem (LoBianco’s) would not have discouraged a skilled artisan from using other known solutions to the problem (Derderian’s). Id. at 15–16. Appellant’s argument that one of ordinary skill in the art would not have combined LoBianco with Derderian (see Appeal Br. 14–15) is not persuasive of reversible error. Appellant contends that LoBianco teaches microspheres that provide the same result as Derderian’s spacers, and thus there is no reason to add the spacers of Derderian to LoBianco. Id. at 15; Reply Br. 2. However, “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’l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007). See also Dystar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356, 1368 (Fed. Cir. 2006) wherein our reviewing Court stated: [A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but Appeal 2019-004539 Application 14/743,124 7 when the “improvement” is technology-independent and the combination of references results in a product or process that is more desirable for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common- sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references. Appellant does not explain why substituting Derderian’s spacers for LoBianco’s microspheres (or adding them to LoBianco) would have been beyond the level of skill in the art or yield unpredictable results. See KSR, 550 U.S. at 417 (“If a person of ordinary skill in the art can implement a predictable variation, and would see the benefit of doing so, § 103 likely bars its patentablity.”). As to Appellant’s argument that LoBianco teaches prevention of shorting (id. at 16), we note that the cited portion of LoBianco discloses that the layer of adhesive between the first and second die prevents shorting, but says nothing in relation to the use of spacers to prevent shorting. See LoBianco col. 2, ll. 6–13. According to Appellant, the combined references fail to teach or suggest a multi-chip module “wherein the third periphery of the stacked first semiconductor device and the second semiconductor device is oriented in a direction transverse to the first periphery and the second periphery” and “wherein at least the first opening and the third opening have at least one of the discrete conductive elements extending therethrough.” Appeal Appeal 2019-004539 Application 14/743,124 8 Br. 14. However, “a mere recitation of the claim elements and a naked assertion that the corresponding elements were not found in the prior art” is insufficient to rebut obviousness. See In re Lovin, 652 F.3d 1349, 1357 (Fed. Cir. 2011). For the foregoing reasons, Appellant has not shown that the Examiner reversibly errs in rejecting claim 1 over LoBianco in view of Derderian. For the same reasons, we sustain the rejection of claims 5, 6, and 10–12 over these references. B. Rejection of claim 13 as obvious over Kurita in view of Derderian Claim 13 comprises limitations similar or identical to those of claim 1, but also requires, inter alia, “each spacer of the spacers surrounding a portion of a discrete conductive element” and the spacers are positioned “separate from the bond pads on the active surface of the first semiconductor device.” Appeal Br. 27 (Claims App’x). The Examiner finds that Kurita teaches the limitations of claim 13 except fails to show each spacer surrounding a portion of a conductive element. Final Act. 5–6. The Examiner relies on Derderian for teaching that each spacer surrounds a portion of a conductive element prevents the conductive elements from collapsing. Id. at 6. Appellant argues that Derderian teaches spacers positioned over the bond pads, and modifying the position of the spacers to be moved away from the bond pads while still surrounding a conductive element has no support in either reference, and is based on hindsight. Appeal Br. 18. The Examiner relies on Kurita, not Derderian, to disclose spacers positioned separate from the bond pads. Final Act. 6. Kurita shows this configuration in FIG. 12, reproduced below: Appeal 2019-004539 Application 14/743,124 9 Kurita FIG. 12 is a cross-sectional view for showing a configuration of a semiconductor device according to an embodiment. Kurita ¶ 80. Semiconductor device 50 includes a first-layer semiconductor chip 54 in which pad electrodes (bond pads) 55 and 56 are arranged in two rows along the centerline. Id. ¶ 140. A second semiconductor chip 11 is stacked on the first chip via a plurality of semi-spherical spacers 57 and an adhesive agent 58. Id. Thus, Kurita teaches the claimed positioning of the bond pads relative to the spacers. As the Examiner points out in the Answer, Derderian’s disclosure is not limited to spacers formed over bond pads. See Ans. 18 (citing Derderian FIG. 1). On this basis, Appellant’s argument that the combined references must result in spacers being over the bond pads is unpersuasive. See Appeal Br. 18. Derderian teaches spacers that surround a portion of a discrete conductive element. Derderian ¶ 68 (“When spacers 22 at least partially encapsulate discrete conductive elements 18, . . . spacers 22 may prevent discrete conductive elements from being collapsed onto one another, bent, Appeal 2019-004539 Application 14/743,124 10 kinked, or otherwise distorted or damaged . . . .”). The Examiner’s rationale for combining Derderian’s disclosure of spacers surrounding a portion of a discrete conductive element with Kurita’s teaching of a multi-chip module (to prevent the elements from collapsing (Final Act. 6)) qualifies as “articulated reasoning with some rational underpinning” that supports the legal conclusion of obviousness. See In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006). “Such a combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.” KSR, 550 U.S. at 416 (“When a work is available in one field, design incentives and other market forces can prompt variations of it, either in the same field or in another. If a person of ordinary skill in the art can implement a predictable variation, and would see the benefit of doing so, § 103 likely bars its patentability.”). We see no reason why improving Kurita’s device with Derderian’s teaching would have been beyond the skill of one of ordinary skill in the art. We sustain the rejection of claim 13 over Kurita in view of Derderian. C. Rejection of claims 16–18 and 20 as obvious over LoBianco in view of Kurita Claims 17, 18, and 20 depend directly from independent claim 16. Appeal Br. 28–29 (Claims App’x). Claim 16 comprises elements similar or identical to those of claim 1. Of relevance to the rejection, claim 16 recites, inter alia, that a central region of the first semiconductor device encompasses bond pads, and that spacers form three common apertures. Id. at 28. Appellant argues claims 16–18 and 20 as a group. Id. at 19–21. We select claim 16 as representative of the group. Claims 17, 18, and 20 stand or fall with claim 16. 37 C.F.R. § 41.37(c)(1)(iv). Appeal 2019-004539 Application 14/743,124 11 The Examiner finds the LoBianco teaches most of the elements of claim 16, including spacers that form three common apertures. Final Act. 6– 7. The Examiner finds that both LoBianco and Kurita conductive elements extending through openings (apertures) between the first and second devices. Ans. 18–20. The Examiner also finds that Kurita discloses centrally located bond pads. Id. at 21. The Examiner concludes that one of ordinary skill in the art would have combined the disclosures of LoBianco and Kurita because the skilled artisan could have selected among a plurality of alternative spacers available, which would be predictable variations of each, other barring patentability, and the spacer variations would have improved similar devices in the same way. Id. at 19–20. In addition, the Examiner determines that the spacers of Kurita would have provided the additional benefits to LoBianco of eliminating the incidence of minute gaps between the first and second devices, as well as providing stability to the stack. Id. at 20 (citing Kurita ¶¶ 17, 96, 100). As in the rejection over LoBianco in view of Derderian, Appellant argues there is no reason to combine the teachings of LoBianco and Kurita. Compare Appeal Br. 14–15 with id. at 20–21. Pointing to LoBianco’s disclosure of microspheres, Appellant contends that Kurita merely duplicates spacers, thus unnecessarily duplicates parts, complicates the device, and increases costs. Id. at 20. Appellant also argues that LoBianco teaches peripheral bond pads, not centrally located bond pads. Id. at 20–21. Appellant contends that “the alleged ‘degree of freedom’ gained by having centrally located bond pads is not supported by any reasoning in the [Final Office Action].” Id. at 20. Appeal 2019-004539 Application 14/743,124 12 Appellant argues that LoBianco contains no disclosure that its microspheres form openings with conductive elements extending therethrough. Id. at 21. Appellant’s arguments fail to establish reversible error in the rejection of claim 16 as obvious over LoBianco in view of Kurita. As discussed supra, a skilled artisan would recognize that Kurita’s spacers—and central spacer location—would improve LoBianco’s device, and we find no reason that such improvement and use of technology would have been beyond the artisan’s skill. See KSR, 550 U.S. at 471. Thus, the combination of references would have been obvious. See also Dystar Textilfarben, 464 F.3d at 1368 (finding an implicit motivation to combine references that result in a more desirable product). Appellant argues that the references would not have been combined, but not that one of ordinary skill in the art was not capable of combining them. See id. We also note that the Examiner’s conclusion that Kurita’s central location of bond pads provides degrees of freedom in connecting conductive elements itself provides “articulated reasoning with some rational underpinning” that supports the legal conclusion of obviousness. See Kahn, 441 F.3d at 988. Turning to Appellant’s argument that LoBianco does not disclose forming openings with conductive elements extending therethrough, we note that the Examiner relies on Kurita, not LoBianco, for this disclosure. Thus, Appellant improperly attacks the references individually, rather than the combination. In re Merck & Co., Inc., 800 F.2d 1091, 1097 (Fed. Cir. 1986) (“Non-obviousness cannot be established by attacking references individually where the rejection is based upon the teachings of a combination of references.”). Each reference cited by the Examiner must be Appeal 2019-004539 Application 14/743,124 13 read, not in isolation, but for what it fairly teaches in combination with the prior art as a whole. See id. For the foregoing reasons, we sustain the rejection of claim 16–18 and 20 over LoBianco in view of Kurita. D. Rejection of claim 4 as obvious over LoBianco and Derderian in view of Akram Appellant argues that claim 4 is patentable “for at least the reasons set forth” regarding claim 1 from which it depends. Appeal Br. 21. Having sustained the rejection of claim 1, we likewise sustain the rejection of claim 4. E. Rejection of claim 14 as obvious over Kurita and Derderian in view of Akram Appellant argues that claim 14 is patentable “for at least the reasons set forth” regarding claim 13 from which it depends. Id. at 22. Having sustained the rejection of claim 13, we likewise sustain the rejection of claim 14. DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1, 5, 6, 10– 12 103(a) LoBianco, Derderian 1, 5, 6, 10– 12 13 103(a) Kurita, Derderian 13 16–18, 20 103(a) LoBianco, Kurita 16–18, 20 4 103(a) LoBianco, Derderian, Akram 4 14 103(a) Kurita, Derderian, Akram 14 Appeal 2019-004539 Application 14/743,124 14 Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed Overall Outcome 1, 4–6, 10– 14, 16–18, 20 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). AFFIRMED Copy with citationCopy as parenthetical citation