Ex Parte SchierDownload PDFPatent Trial and Appeal BoardMar 17, 201712776110 (P.T.A.B. Mar. 17, 2017) 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. 12/776,110 05/07/2010 Herbert SCHIER V0216US 1544 91286 7590 Harness, Dickey & Pierce, P.L.C. (Lam) P.O. Box 828 Bloomfield Hills, MI 48303 EXAMINER PHAM, THOMAS T ART UNIT PAPER NUMBER 1713 NOTIFICATION DATE DELIVERY MODE 03/21/2017 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): s stevens @ hdp .com troymailroom @hdp. com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte HERBERT SCHIER Appeal 2015-001628 Application 12/776,110 Technology Center 1700 Before CATHERINE Q. TIMM, N. WHITNEY WILSON, and CHRISTOPHER C. KENNEDY, Administrative Patent Judges. WILSON, Administrative Patent Judge. DECISION ON APPEAL Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s May 7, 2013 decision finally rejecting claims 20—31 (“Final Act.”). We have jurisdiction over the appeal under 35 U.S.C. § 6(b). We affirm-in-part. 1 Appellants identify the Real Party in Interest as LAM Research AG (Appeal Br. 1). Appeal 2015-001628 Application 12/776,110 CLAIMED SUBJECT MATTER Appellant’s invention is directed to a method for treating a substrate — in particular stripping a photoresist — using an acid composition comprising a mixture of sulfuric acid and periodic acid at a temperature of 110°—145°C by dispensing the acid composition on the substrate which is mounted on a spinning chuck for 1 to 5 minutes (Spec. 3, 9). Details of the claimed method are set forth in Claim 20, as reproduced below from the Claims Appendix: 20. A method for treating a substrate, comprising: spinning a chuck having the substrate mounted thereon; and dispensing a mixture of sulfuric acid and periodic acid onto the substrate as the chuck is spinning, the mixture being at a temperature in the range of 110°C to 145°C, such that a dwell time of the process mixture on the substrate is from one to five minutes; wherein sulfuric acid is present in said mixture at a range of 70-99.5 wt.% and periodic acid is present in said mixture at a range of 0.1-10 wt.%, calculated as TEICE and H2SO4. REJECTIONS I. Claims 20-28 and 31 are rejected under 35 U.S.C. § 103(a) as being unpatentable over Cooper2 in view of Tsung-Kuei.3 II. Claims 29 and 30 are rejected under 35 U.S.C. § 103(a) as being unpatentable over Cooper in view of Tsung-Kuei, and further in view of Yashima.4 2 Cooper et al., US 2009/0281016 Al, published November 12, 2009. 3 Tsung-Kuei, US 2003/0196986 Al, published October 23, 2003. 4 Yashima, US 2008/0124267 Al, published May 29, 2008. 2 Appeal 2015-001628 Application 12/776,110 DISCUSSION Rejection I. With the exception of claim 31, Appellant argues all of the claims subject to Rejection I together. Accordingly, we focus our analysis on the rejection of claim 20, but address claim 31 separately. The Examiner finds that Cooper teaches a method for treating a semiconductor substrate, such as etching a photoresist layer on a wafer, comprising contacting the substrate with a mixture of sulfuric acid and periodic acid, the mixture being at a temperature in the range of 20°C to 200°C, for a period of 10 seconds to 60 minutes (Final Act. 2, citing Cooper, 17, 30, 31, 68, and 81). The Examiner implicitly, and correctly, finds that the temperature range and contacting period disclosed in Cooper overlap with the corresponding values in claim 20 and, therefore, those values would have been obvious (Final Act. 2—3). The Examiner further finds that Cooper discloses that the contact between the acid mixture and the substrate may be accomplished in any suitable manner, and that the sulfuric acid may be present at a concentration of about 99 wt% while the periodic acid may be present at an amount of about 1 wt% (Final Act. 3, citing Cooper, H 34, 67, 75, and 79). The Examiner also finds that Cooper is silent with regards to the specific details of applying the acid mixture to the substrate (i.e. the claim limitations describing a spinning chuck having the substrate mounted thereon) {id.). The Examiner relies on the disclosure of Tsung-Kuei as teaching a method of wet etching a layer on a semiconductor substrate using an etchant, wherein the etchant is advantageously injected and form puddled on the substrate while the substrate is rotated on a spin chuck to improve etch 3 Appeal 2015-001628 Application 12/776,110 uniformity, increase etch rate and reduce etchant consumption (Final Act. 3, citing Tsung-Kuei, Abstract, || 6—9, and 75). The Examiner concludes that: it would have been obvious to one of ordinary skill in the art at the time the invention was made, in routine experimentations, to use the method of Tsung-Kuei's as described above to etch the photoresist layer of Cooper's by dispensing the above mixture of sulfuric acid and periodic acid of Cooper's onto the substrate mounted on a spinning chuck, wherein the mixture of sulfuric acid and periodic acid is at a temperature in a range of 110-145°C and for a dwell time in the range of 1-5 minutes because Cooper is silent about the specific details on contacting the substrate with the mixture of sulfuric acid and periodic acid by spraying in a single wafer apparatus, and Tsung-Kuei teaches that such method advantageously improve etch uniformity, increasing etch rate, and reducing etchant consumption. (Final Act. 3—4). Appellant does not dispute that Cooper teaches a composition which can contain both sulfuric and periodic acids in the requisite amounts, but instead argues that Cooper’s specific disclosures for mixtures containing both sulfuric and periodic acids fall outside the claimed temperature and contact time ranges (Appeal Br. 2). In particular, Appellant contends that Cooper discloses that mixtures of sulfuric and periodic acid are effective “at temperatures between 60 and 95°C and reaction times of 30-60 minutes, depending on type of implant, dose, and energy” (Appeal Br. 2, citing Cooper, 177). Therefore, according to Appellant, it would not have been obvious to arrive at the claimed times and temperatures through routine optimization (Appeal Br. 3). “A prima facie case of obviousness may be made when the only difference from the prior art is a difference in the range or value of a particular variable. In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir. 2003); In 4 Appeal 2015-001628 Application 12/776,110 re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990); In re Kumar, 418 F.3d 1361, 1366 (Fed. Cir. 2005). Where “the difference between the claimed invention and the prior art is some range or other variable within the claims . . . , the [patentee] must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results . . . . ” Woodruff, 919 F.2d at 1578 (internal citations omitted). In this instance, Appellant has not shown reversible error in the Examiner’s findings that Cooper discloses each of the components of the claimed sulfuric acid/periodic acid mixture in amounts and at temperatures which overlap (or completely encompass) the claimed ranges. In particular, Cooper discloses the use of a composition for removing photoresist material which includes at least one mineral acid and at least one oxidizing agent (Cooper, Abstract). The mineral acid can be sulfuric acid (130) which can be present in an amount from about 85 to about 99 wt% (1 34). The oxidizing agent can be periodic acid (131) which can be present in an amount from about 1 to about 15 wt% (134). The composition can be contacted with the photoresist at a temperature from about 20° to about 200°C, and for a period of time from about 10 seconds to about 60 minutes (1 68). Thus, the claimed compositional, temperature, and contacting time ranges overlap with the disclosures of Cooper and, therefore, would have been prima facie obvious in view of Cooper. Peterson, 315 F.3d at 1329. In response, Appellant argues that “the disclosure of Cooper that is particular to mixtures of sulfuric acid and periodic acid teaches that such mixtures, at concentrations of 5-15% periodic acid, ‘are effective at removing high-density implanted resist at temperatures between 60 and 95°C and reaction times of 30-60 minutes, depending on type of implant, dose and 5 Appeal 2015-001628 Application 12/776,110 energy’” (Appeal Br. 2, citing Cooper 177). Because these temperature and time ranges do not overlap with the claimed ranges, Appellant argues that they would not have rendered the claimed ranges obvious (Appeal Br. 2—3). This argument is not persuasive. A prior art reference is analyzed from the vantage point of all that it teaches one of ordinary skill in the art. See In re Lemelson, 397 F.2d 1006, 1009 (CCPA 1968) (“The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain.”) Moreover, a reference is not limited to its preferred embodiment, but must be evaluated for all of its teachings, including its teachings of non-preferred embodiments. See In re Burckel, 592 F.2d 1175, 1179 (CCPA 1979). In this instance, that a single example/embodiment describes ranges that fall outside the claimed ranges is not sufficient to overcome the prima facie case of obviousness set forth by the Examiner. Appellant also argues that the examples in the Specification show that the claimed ranges show unexpected results which are sufficient to overcome the prima facie case of obviousness (Appeal Br. 3). It is well settled that Appellant has the burden of showing unexpected results. In re Freeman, 474 F.2d 1318, 1324 (CCPA 1973); In reKlosak, 455 F.2d 1077, 1080 (CCPA 1972). Such burden requires Appellant to proffer factual evidence that actually shows unexpected results relative to the closest prior art (see In re Baxter Travenol Labs., 952 F.2d 388, 392 (Fed. Cir. 1991)), and that is reasonably commensurate in scope with the protection sought by claim 34 on appeal (In re Grasselli, 713 F.2d 731, 743 (Fed. Cir. 1983); In re Clemens, 622 F.2d 1029, 1035 (CCPA 1980); In re Hyson, 453 F.2d 764, 786 (CCPA 6 Appeal 2015-001628 Application 12/776,110 1972)). The extent of the showing relied upon by Appellant must reasonably support the entire scope of the claims at issue. See In re Harris, 409 F.3d 1339, 1344 (Fed. Cir. 2005). In this instance, in the Appeal Brief, Appellant refer to the existence of the experimental data set forth on pages 10-20 of the Specification, and quote a short conclusion from the Specification: As can be seen, in the lower temperature range of the comparative art [(Cooper),] there was incomplete removal, redeposition, precipitation and wafer spoilage. In contrast, the elevated temperatures of the technology of the present application achieve complete resist removal at reduced treatment times. (Appeal Br. 3). Appellant’s failure to provide an explanation in the Appeal Brief how the data allegedly demonstrates unexpected results is sufficient for us to conclude that Appellant has not met its burden to overcome the prima facie case of obviousness. See, e.g., 37 C.F.R. § 41.41 (b)(2): Any argument raised in the reply brief which was not raised in the appeal brief, or is not responsive to an argument raised in the examiner’s answer, including any designated new ground of rejection, will not be considered by the Board for purposes of the present appeal, unless good cause is shown. Nevertheless, the Examiner reviewed the data in the passages of the Specification cited by Appellant and determined that it did not overcome the prima facie case of obviousness (Ans. 7—8). Among other deficiencies in the data, the Examiner finds that the data does not show improved results for compositions containing different concentrations of the components, or which have different dwell times on the substrate (Ans. 9). Appellant does not persuasively dispute this finding. Because the burden rests with Appellant to establish that the supplied evidentiary showing is commensurate in scope with 7 Appeal 2015-001628 Application 12/776,110 the claimed subject matter, the failure to do requires us to reject the proposed showing of unexpected results. See Klosak, 455 F.2d at 1080. Appellant also argues that Tsung-Kuei’s etching technique requires a long contact time (20-30 minutes) between the substrate and the acid solution (Appeal Br. 4, citing Tsung-Kuei, 9, 18, and Table 1). Therefore, according to Appellant, the combined disclosures of Tsung-Kuei and Cooper “is entirely inconsistent with the process parameters recited in claim 20, and, in particular ... a dwell time of the process mixture on the substrate . . . from one to five minutes” (Appeal Br. 4). This argument is not persuasive, essentially for the reasons set forth at page 9 of the Answer, namely that Cooper discloses dwell times (10 seconds to 60 minutes) which overlap with the claimed times, and that a detailed evaluation of Cooper’s disclosure suggests a dwell time of 1 minute for single wafer processing (Ans. 9). Thus, we conclude that, based on the evidence of record, Appellant has not shown reversible error in the rejection of claim 20 over Cooper in view of Tsung-Kuei. Appellant separately argues claim 31, which recites that the spinning of the substrate and the dispensing of the acid mixture are controlled to produce a shear flow rate of approximately 1.5 liters/min across the substrate. The Examiner finds that this limitation is suggested by Tsung-Kuei, which teaches injecting the etchant at a flow rate of 0.6—5 liters/min for 3 seconds while spinning the wafer at 0-50 rpm, which means that the shear flow rate for at least the point of contact is 0.6—5 liters per minute. We agree with Appellant that construing the term “shear flow rate” in claim 31 to cover the short period that the etchant is dispersed onto the substrate in Tsung-Kuei is not reasonable in light of the claim language, which suggests that the shear flow rate should 8 Appeal 2015-001628 Application 12/776,110 be measured over the course of the entire dwell time. Thus, we determine that the Examiner’s findings with respect to the shear flow rate of Tsung-Kuei do not support a finding of obviousness, and reverse the rejection of claim 31. Rejection II. Rejection II is directed to claims 29 and 30, which recite the recycling of the mixture of sulfuric and periodic acids (claim 30 recites recycling by reoxidizing the mixture with ozone). The Examiner finds that Yashima teaches a method to recycle waste by-products from etching of a substrate with an etchant, so that the by-products may be recycled to be used as the etchant again, and that the recycling prevents adverse effects on the environment (Final Act. 5, citing Yashima, H 5—24). Based on the disclosure in Yashima and Cooper’s teaching that periodic acid may be generated in site by oxidizing an iodine compound with ozone, the Examiner concludes that it would have been obvious to recycle the periodic acid using ozone in order to prevent adverse environmental effects (Final Act. 5—6). Appellant argues that Yashima does not disclose using the recycled waste by-products in the original products and, therefore, that it does not support the Examiner’s obviousness conclusion (Appeal Br. 5). This argument is not persuasive. As noted by the Examiner, the clear use of a recycled product is to use it, and Cooper discloses recycling the etching composition (Ans. 10, citing Cooper, 171). As held by the Supreme Court, “[a] person of ordinary skill is also a person of ordinary creativity, not an automaton.” KSRInt’l Co. v. Teleflex, Inc., 550 U.S. 398, 421 (2007). In view of this holding, the preponderance of the evidence supports the 9 Appeal 2015-001628 Application 12/776,110 Examiner’s determination that recycling of the mixture would have been obvious in light of the combined teachings of the prior art. CONCLUSION We AFFIRM the rejection of claims 20-28 under 35 U.S.C. § 103(a) as being unpatentable over Cooper in view of Tsung-Kuei. We REVERSE the rejection of claim 31 over Cooper in view of Tsung-Kuei. We AFFIRM the rejection of claims 29 and 30 under 35 U.S.C. § 103(a) as being unpatentable over Cooper in view of Tsung-Kuei, and further in view of Yashima. 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)(l)(iv). AFFIRMED-IN-PART 10 Copy with citationCopy as parenthetical citation