Ex Parte George et alDownload PDFPatent Trial and Appeal BoardOct 10, 201211564134 (P.T.A.B. Oct. 10, 2012) Copy Citation UNITED STATES PATENT AND TRADEMARKOFFICE 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. 11/564,134 11/28/2006 Rene George MAT-8C 2073 21833 7590 10/10/2012 PRITZKAU PATENT GROUP, LLC 993 GAPTER ROAD BOULDER, CO 80303 EXAMINER DHINGRA, RAKESH KUMAR ART UNIT PAPER NUMBER 1716 MAIL DATE DELIVERY MODE 10/10/2012 PAPER 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. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte RENE GEORGE, ANDREAS KADAVANICH, DANIEL J. DEVINE, STEPHEN E. SAVAS, JOHN ZAJAC, and HONGCHING SHAN ____________________ Appeal 2011-005808 Application 11/564,134 Technology Center 1700 ____________________ Before ADRIENE LEPIANE HANLON, HUBERT C. LORIN, and CATHERINE Q. TIMM, Administrative Patent Judges. TIMM, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF CASE Appellants seek review under 35 U.S.C. § 134 of the Examiner’s decision to reject claims 7-10 and 12-20. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM-IN-PART. Appeal 2011-005808 Application 11/564,134 2 Appellants’ claims relate to an electrostatic shield used in an inductively coupled plasma reactor (see independent claims 7, 10, 13, and 16 as reproduced in the Appendix to the Brief). According to Appellants’ Specification, electrostatic shields were known in the art and used to reduce undesirable electrostatic fields and capacitive coupling (Spec. ¶ 5; see also US 5,534,231 to Savas incorporated by reference at Spec. ¶ 5). According to the Specification, “[a]n electrostatic shield of any type may be used with an inductively coupled plasma source, but for RF power to penetrate the shield, a slotted electrostatic shield has been found to be an effective approach” (Spec. ¶ 5). Appellants’ shield is a slotted electrostatic shield that is said to be an improvement over prior art electrostatic shields (Spec. ¶¶ 5-13). The prior art slotted shields discussed by Appellants are of two varieties (id.). One type of prior art shield has a shape that varies in radii relative to the axis of symmetry (Spec. ¶ 5, incorporating by reference U.S. Patent 5,534,231 to Savas, which shows a cylindrical dome-topped slotted shield, and Spec. ¶7, discussing a frustoconical slotted shield). Appellants’ Figure 1, which shows the prior art frustoconical shield at 101 between a plasma containing vessel 104 and a plasma generation coil 102, is reproduced below: App App slots type dime Paten emb eal 2011-0 lication 11 Diagram The prio 103 of co of prior ar nsions but t 5,234,52 odiment of 05808 /564,134 matic per r art frusto nstant wid t slotted sh an axially 9 to John Johnson’ spective il assembl conical sh th around ield discu uniform c son (Spec. s two-part 3 lustration y (Spec. ¶ ield of Fig its circumf ssed by A ylindrical ¶ 12). Fig shield, is r of prior ar 17) ure 1 has erence (Sp ppellants h shield sha ure 5 of J eproduced t frustocon regularly s ec. ¶ 7). as varying pe as show ohnson, sh below: ical shield paced The other slot n by U.S owing an . App App (John relat form widt the s axial 28). eal 2011-0 lication 11 Perspe Johnson son, col. ive to the o ed by the h of the sli hield, and location o 05808 /564,134 ctive view ’s shield in 5, ll. 61-65 uter porti two shield t varies th changing f the capa of an em (Johnson cludes tw ). Johnso on 44 to ch portions ( e amount o the axial p citive coup 4 bodiment o , col. 2, ll o concentr n disclose ange the w Johnson, c f capaciti osition and ling (John f Johnson . 7-8) ic shield p s rotating t idth and ol. 6, ll. 1 ve couplin length of son, col. 6 ’s two-pie ortions 42 he inner p length of t 9-24). Ch g provided the slit va , ll. 1-6 an ce shield and 44 ortion 42 he slit anging the through ries the d ll. 19- Appeal 2011-005808 Application 11/564,134 5 Appellants’ electrostatic shield combines a radially varied shape, such as the frustoconical shape of Figure 1, with a variable slot arrangement, such as the slot arrangement shown in Johnsons’ Figure 5 (Spec. ¶ 15). According to Appellants, the combination produces a plasma density having a given radial variation characteristic across the surface being treated that is different from the plasma density radial characteristic created by the prior art shields (id.). This radially varying plasma density, according to Appellants, is not taught by the prior art (Spec. ¶ 12). Appellants’ Figure 10a is reproduced below to illustrate an embodiment of their electrostatic shield: Diagrammatic perspective view of a two-part electrostatic shield assembly 600 (Spec. ¶¶ 30) Appeal 2011-005808 Application 11/564,134 6 Appellants explain that Again considering the aforedescribed invention by Johnson, only a cylindrical shield is taught. The highly advantageous two-part slotted shield of the present invention, for varying plasma radial uniformity, is not a cylindrical shield. The present invention recognizes that a shield with a shape that covers a range of radii relative to the symmetry axis of the system (i.e., part of a cone surface, flat-top, or dome surface) is highly advantageous. With this type of shield, the slot variability is capable of producing a change in the radial distribution of power injection into the plasma. This change in the power injection distribution results in a change in the radial density distribution of the plasma. (Spec. ¶ 73.) The Examiner rejects claims 7, 9, and 13-20 under 35 U.S.C. § 103(a) as obvious over Qian1 in view of Johnson2 (Ans. 4-7 and 9-13).3 To reject claims 8, 10, and 12, the Examiner adds Daviet4 as evidence of obviousness. Appellants argue various claims under separate headings. We, therefore, consider those claims separately pursuant to 37 C.F.R. § 41.37(c)(1)(vii). Claims not argued under separate headings stand or fall with the argued claim upon which they depend. 1 Qian, US 5,540,800 patented Jul. 30, 1996. 2 Johnson, US 5,234,529 patented Aug. 10, 1993. 3 Initially, the Examiner rejected claims 7, 9, 10, 16, and 20 over Appellants’ Admitted Prior Art (Figure 1) in view of Johnson and Qian (Non-Final Rej. 3). However, the Examiner no longer relies upon Appellants’ Figure 1 in any of the rejections (Final Rej. 3; Ans. 4-13). 4 Daviet, US 6,056,848 patented May 2, 2000. Appeal 2011-005808 Application 11/564,134 7 OPINION A. The Rejection of Claims 7, 9, and 13-20 over Qian and Johnson 1. Claim 7 Claim 7 reads as follows: 7. In a processing chamber that uses an inductively coupled plasma source defining an axis of symmetry and which produces a plasma density having a given radial variation characteristic across a treatment surface of a treatment object therein using a given electrostatic shield, an apparatus comprising: an electrostatic shield arrangement including at least a sidewall arrangement having a shape that extends through a range of radii relative to said axis of symmetry to replace said given electrostatic shield to provide for producing a modified radial variation characteristic across said treatment surface which is different than said given radial variation characteristic and where said electrostatic shield arrangement includes at least a first, inner shield member and a second, outer shield member, said inner shield member defining a first aperture pattern and said outer shield member defining a second aperture pattern, and the outer shield member nests proximate to the inner shield member with the inner and outer shield members being supported for rotation relative to one another such that the first aperture pattern cooperates with the second aperture pattern in a way which provides a range in said modified radial variation characteristic across said treatment surface by defining an effective aperture pattern that is made up of a plurality of effective apertures in which each effective aperture extends through at least a portion of the range of radii relative to the axis of symmetry and each effective aperture includes a width that varies at least partially along the length of that effective aperture to produce the modified radial variation characteristic. (Claims App. at Br. 30.) Appeal 2011-005808 Application 11/564,134 8 As a first matter, we note that the claim is directed to an apparatus. “Claims drawn to an apparatus must distinguish from the prior art in terms of structure rather than function.” In re Danly, 263 F.2d 844, 848 (CCPA 1959). In terms of positively recited structure, the claim requires an electrostatic shield having (1) a sidewall arrangement having a shape that extends through a range of radii relative to said axis of symmetry, such as a dome- shape or frustoconical shape; and (2) nested inner and outer shield members; a. each with an aperture pattern, b. supported for rotation relative to one another such that the first aperture pattern cooperates with the second aperture pattern to define an effective aperture pattern, c. each effective aperture extending through at least a portion of the range of radii relative to the axis of symmetry, d. each effective aperture including a width that varies at least partially along the length of that effective aperture. The language directed to producing a plasma density having a modified radial variation characteristic across said treatment surface is functional in nature. We consider this language in so far as it defines structures patentably distinguishable from structures described and suggested by the prior art. There is no dispute that Qian describes, as found by the Examiner, a two member electrostatic shield having a dome-shape, i.e., a shape that Appeal 2011-005808 Application 11/564,134 9 extends through a range of radii relative to the axis of symmetry as required by claim 7 (Compare Br. 11-12 with Ans. 4). Nor is there any dispute that Johnson describes an electrostatic shield with two members (inner and outer portions 42, 44) that can be rotated relative to each other so that the aperture patterns therein can cooperate to control capacitive coupling (Compare Br. 9-11 with Ans. 5). While Appellants make a myriad of arguments, many of which focus on the individual teachings in each of the references, the central issue in this appeal can be formulated as: Has the Examiner erred in finding that Johnson provides a reason for including the rotatable shield members having the cooperating pattern of apertures of Johnson in the dome-shaped electrostatic shield of Qian such that the modified structure meets all the structural requirements of claim 7? We determine that a preponderance of the evidence supports the Examiner’s conclusion of obviousness and, therefore, answer this question in the negative. In addition to the facts discussed above, the relevant facts are as follows. The prior art as a whole provides evidence that electrostatic shields of various shapes, including dome-shaped shields, and with or without slots, slits, and apertures were known in the art (Qian, Figs. 1-2 and col. 4, ll. 33- 41; see also Spec. ¶ 5). Qian’s Figure 2 is reproduced below: Appeal 2011-005808 Application 11/564,134 10 Expanded perspective side view showing Qian’s Faraday shield (Qian, col. 2, ll. 63-65) In explaining the background of Qian’s invention, Qian states that: In order to reduce such capacitive coupling, a Faraday shield [i.e., an electrostatic shield] can be placed between the coil antenna and the plasma. The Faraday shield is a grounded thin conductive layer. The Faraday shield, however, must have thin elongate openings therein lying in directions perpendicular to the windings of the RF coil antenna, in order to suppress any eddy Appeal 2011-005808 Application 11/564,134 11 currents which would otherwise tend to be induced in the Faraday shield. These openings, however, tend to admit some electric fields from the coil antenna to the plasma, thereby permitting some capacitive coupling. (Qian, col. 1, ll. 49-59.) Qian describes a two-layer Faraday shield 80 (electrostatic shield) having first and second layers 82 and 86 conforming to the dome ceiling of the plasma reactor 25 (Qian, col. 3, ll. 52-62). Qian offsets the slots 84 and 88 in the shield layers so that there is no aperture through which an electric field can pass (Qian, col. 3, l. 66 to col. 4, l. 6). Accordingly, the shield 80 “provides far greater suppression of capacitive coupling” (Qian, col. 4, ll. 6- 9). Johnson, as discussed above, also describes an electrostatic shield for suppressing capacitive coupling, but Johnson’s inner and outer shield portions are rotatable so that slots in the inner and outer shield portions define effective apertures that vary in width and length so the degree of capacitive coupling allowed through the shield can be varied for tuning the characteristics of the plasma (Johnson, col. 2, ll. 24-33). Johnson discloses that such tuning is desirable when more RF power is required than is available in a totally inductively coupled plasma (Johnson, col. 4, ll. 23-39). “The ‘existence of a reason for a person of ordinary skill to combine references” is a question of fact’.” In re Suong-Hyu Hyon, 679 F.3d 1363, 1365-66 (Fed. Cir. 2012) (quoting In re Constr. Equip. Co., 665 F.3d 1254, 1255 (Fed.Cir.2011)). We review this question under a preponderance of the evidence standard of proof. In re Kahn, 441 F.3d 977, 989 (Fed. Cir. 2006). Appeal 2011-005808 Application 11/564,134 12 The prior art provides evidence that those of ordinary skill in the art understood how to obtain the level of capacitive coupling desired in an electrostatic shield. When reduced capacitive coupling is desired, one would have blocked the apertures as taught by Qian. However, when one desired to tune the characteristics of the plasma, one would have constructed the shield members with the variable aperture patterns taught by Johnson and made the members rotatable to accomplish the tuning as described by Johnson. A preponderance of the evidence supports the Examiner’s finding of a reason to combine the teachings of Qian and Johnson as proposed. We agree with Appellants that Johnson only discloses using the ratio of open area to closed area of the effective apertures to change the amount of coupling to the plasma, and does not teach a plasma density having “a modified radial variation characteristic across said treatment surface” as recited by claim 7 (Br. 9-10; Reply Br. 4-5). However, “any need or problem known in the field of endeavor at the time of invention and addressed by the patent can provide a reason for combining the elements in the manner claimed.” KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 420 (2007). Therefore, this difference in purpose does not indicate an error in the Examiner’s finding of a reason to combine. Moreover, Appellants appear to have merely discovered a new benefit, i.e., modified radial variation in plasma density, for a shield having a range of radii relative to the axis of symmetry and variable apertures. This new plasma density benefit need not have been recognized in the prior art to have rendered the claim obvious. Boston Scientific v. Cordis, 554 F.3d 982, Appeal 2011-005808 Application 11/564,134 13 991 (Fed. Cir. 2009). We emphasize that the claim is directed to an apparatus and, therefore, must be distinguished from the prior art in terms of structure rather than function. There is no evidence that the function of producing a modified radial variation characteristic requires a structure different from that suggested by the prior art combination. We sustain the rejection of claim 7 and claim 20, which stands or falls therewith, as obvious over Qian in view of Johnson. 2. Claims 9, 13-15, and 17-19 Claims 9, 13-15, and 17-19 specifically require the shield members be frustoconical (see claims 9, 13, and 17). The Examiner finds that the dome- shaped shield members of Qian are frustoconical in configuration (see, e.g., Ans. 6). However, a dome has a hemispherical shape, not the truncated conical shape of a frustoconical structure such as that shown in Appellants’ Figure 1.5 We agree with Appellants that the Examiner has not established that Qian in view of Johnson teaches or suggests a frustoconical shield member. Therefore, we do not sustain the rejection of claims 9, 13-15, and 17-19 over Qian in view of Johnson. 3. Claim 16 With respect to claim 16, Appellants rely upon the same arguments advanced against the rejection of claim 7 (Br. 21-22). For the reasons we explained above in reference to the rejection of claim 7, we sustain the rejection of claim 16. 5 The prior rejection that relied upon Figure 1 as well as Qian and Johnson as evidence of obvious is not before us. Therefore, we do not review that rejection. Appeal 2011-005808 Application 11/564,134 14 B. The Rejection of Claims 8, 10, and 12 over Qian, Johnson, and Daviet 1. Claim 8 Claim 8 is dependent on claim 7 and further requires “a rotation arrangement for sensing the modified radial variation characteristic and for rotating one of the inner shield member and the outer shield member responsive to a sensed value of the modified radial variation characteristic.” The Examiner acknowledges that Qian in view of Johnson does not teach that the rotation arrangement is for the functions recited in claim 8 (Ans. 7). However, the Examiner concludes that it would have been obvious to one of ordinary skill in the art to automate the shield member moving arrangement of Qian and Johnson to control capacitive coupling (Ans. 7 and 42). Appellants contend that the prior art would not lead one to conclude that a modified radial variation characteristic would even be produced much less suggest sensing that characteristic and rotating in response to the sensing (Br. 25-26). The first question to be asked is: What structure is encompassed by Appellants’ claim limitation? To answer that question, we consult the Specification to give the words of the claim context. See U.S. v. Adams, 383 U.S. 39, 49 (1966) ("[I]t is fundamental that claims are to be construed in the light of the specifications and both are to be read with a view to ascertaining the invention."). Appeal 2011-005808 Application 11/564,134 15 The claim 8 limitation is in the form of a function without a recitation of structure. Looking to the Specification for guidance as to what structure is intended to correspond with the function, we find that the only mention of sensing and controlling the rotating in response to the sensing is found in the Specification at paragraph 50, which states: In an automatic plasma tuning implementation, real-time inputs can be employed using sensors measuring parameters at a wafer surface such as, for example, etch and/or deposition rates at specific positions on the surface of the wafer. For instance, deposition and etch rates can be measured for certain materials using optical reflectometry. Moreover, any suitable optical emission techniques can be used to measure etch and/or deposition rates at localized, spaced apart positions for use in determining uniformity. A wide variety of motor and control arrangements may be used in such automatic implementations. (Spec. ¶ 50.) Paragraph 51 describes automated control schemes. The control schemes involve rotating the shield members relative to one another to vary the radial RF penetration by varying the shape or size of the slots (Spec. ¶ 51). Moreover, the modified radial variation characteristic is not directly sensed, rather measurements indicative of uniformity are preformed, e.g., measurements of etch rate or deposition rate (Spec. ¶ 51). Neither the type of sensor nor its structure is identified in the Specification. Johnson suggests using a “process monitoring and controlling mechanism” to move a lever that rotates the inner shield relative to the outer shield to displace the slits and vary capacitive coupling (Johnson, col. 6, ll. 7-16). Daviet discusses using elevational or rotational actuators for lifting or Appeal 2011-005808 Application 11/564,134 16 moving shield portions to provide gaps that allow capacitive coupling (Daviet, col. 6, ll. 2-9). The prior art indicates that automating and controlling the rotation by known monitoring and process control means was known in the art. Given the dome-shaped structure with variable apertures suggested by the prior art has a structure that appears capable of accomplishing a modified radial variation of plasma density, there is no evidence on this record that the automation structures one of ordinary skill in the art would have used to control etching, deposition, and capacitive coupling in the structure suggested by the combination of Qian and Johnson are patentability distinguishable from the “rotation arrangement” of claim 8. A preponderance of the evidence supports the Examiner’s rejection of claim 8. We, therefore, sustain the rejection of claim 8. 2. Claims 10 and 12 Claims 10 and 12 require that the first shield member be frustoconical in configuration (see Claim 10). The Examiner relies upon the response to claim 9, i.e., that Qian’s dome-shaped shield could be considered generally frustoconical (Ans. 43; see also Ans. 30). As we stated above with regard to the rejection of claim 9, a dome is not frustoconical. We do not sustain the rejection of claims 10 and 12. CONCLUSION We sustain the rejection of claims 7, 16, and 20 as obvious over Qian and Johnson. We do not sustain the rejection of claims 9, 13-15, and 17-19 over Qian in view of Johnson. Appeal 2011-005808 Application 11/564,134 17 We sustain the rejection of claim 8 over Qian, Johnson, and Daviet. We do not sustain the rejection of 10 and 12 over Qian, Johnson, and Daviet. DECISION The Examiner’s decision is affirmed-in-part. 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)(1). AFFIRMED-IN-PART cam Copy with citationCopy as parenthetical citation