Ex Parte Tao et al

Patent Trial and Appeal BoardNov 26, 2012

11641334 (P.T.A.B. Nov. 26, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte TENG CHAO D. TAO, WILLIAM D. LEE, MARVIN R. LAFONTAINE, and ASHWIN M. PUROHIT ____________ Appeal 2011-009056 Application 11/641,334 Technology Center 2800 ____________ Before MARC S. HOFF, CARLA M. KRIVAK, and ELENI MANTIS MERCADER , Administrative Patent Judges. MANTIS MERCADER, Administrative Patent Judge. DECISION ON APPEAL Appeal 2011-009056 Application 11/641,334 2 STATEMENT OF THE CASE Appellants appeal under 35 U.S.C. § 134(a) from a final rejection of claims 1-25. We have jurisdiction under 35 U.S.C. § 6(b). We reverse. THE INVENTION Appellants’ claimed invention is directed to an electrostatic clamp (ESC) 100 having a first electrode associated with an annulus, wherein the first electrode 106 is electrically connected to a first voltage potential, and a second electrode 108 is associated with a central disk and is electrically connected to a second voltage potential. The first electrode and second electrode are electrically isolated from one another and are configured to be independently charged, wherein the first voltage potential is operable to substantially clamp a workpiece to the annulus via a first clamping force, and wherein the second voltage potential is operable to provide a second clamping force to the workpiece and can substantially compensate for forces associated with the backside gas pressure. See Fig. 1; Spec. 5:4-13. Independent claim 1, reproduced below, is illustrative of the subject matter on appeal. 1. An electrostatic clamp for clamping a workpiece, the electrostatic clamp comprising: a clamping plate, comprising: an annulus comprising a first layer having a first surface associated therewith, wherein the first surface is configured to contact a peripheral region of a surface of the workpiece; a central disk comprising a second layer having a second surface, wherein the annulus generally encircles the central disk, and wherein the second surface is generally recessed from Appeal 2011-009056 Application 11/641,334 3 the first surface, therein generally defining a gap between the second surface and the surface of the workpiece; and one or more backside gas delivery apertures in fluid communication with a gas supply and positioned proximate to an interface between the annulus and the central disk; a first electrode associated with the annulus, wherein the first electrode is electrically connected to a first voltage potential; and a second electrode associated with the central disk, wherein the second electrode is electrically connected to a second voltage potential, and wherein the first electrode and second electrode are electrically isolated from one another. REFERENCES and REJECTIONS The Examiner rejected claims 1-3, 5-7, 9-11, 16-18, 20, 21, 23, and 25 under 35 U.S.C. § 103(a) based on the teachings of U.S. Patent Application Publication No. 2003/0161088 A1, published August 28, 2003 (“Migita”) and U.S. Patent Application Publication No. 2006/0171094 A1, published August 3, 2006 (“Muka”). Ans. 4-9. The Examiner rejected claim 4 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and U.S. Patent No. 6,108,189, issued August 22, 2000 (“Weldon”). Ans. 9. The Examiner rejected claim 8 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and U.S. Patent No. 6,433,346 B1, issued August 13, 2002 (“Hirayanagi”). Ans. 10. The Examiner rejected claims 12, 15, and 22 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and U.S. Patent Application Publication No. 2005/0219786 A1, published October 6, 2005 (“Brown”). Ans. 10-11. Appeal 2011-009056 Application 11/641,334 4 The Examiner rejected claim 13 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, Brown, and U.S. Patent No. 5,838,528, issued November 17, 1998 (“Os”). Ans. 11-12. The Examiner rejected claim 14 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, Brown, Os, and U.S. Patent No. 5,754,391, issued May 19, 1998 (“Bates”). Ans. 12-13. The Examiner rejected claims 17 and 18 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and U.S. Patent Application Publication No. 2007/0109714 A1, published May 17, 2007 (“Chung”). Ans. 13-14. The Examiner rejected claim 19 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and U.S. Patent No. 6,552,892 B2, issued April 22, 2003 (“Carroll”). Ans. 14-15. The Examiner rejected claim 24 under 35 U.S.C. § 103(a) based on the teachings of Migita, Muka, and Bates. Ans. 15-16. ISSUE The pivotal issue is whether the combination of Migita and Muka teaches the limitations of: a first electrode associated with the annulus, wherein the first electrode is electrically connected to a first voltage potential; and a second electrode associated with the central disk, wherein the second electrode is electrically connected to a second voltage potential, and wherein the first electrode and second electrode are electrically isolated from one another as recited in independent claim 1. Appeal 2011-009056 Application 11/641,334 5 PRINCIPLE OF LAW A reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant. The degree of teaching away will of course depend on the particular facts; in general, a reference will teach away if it suggests that the line of development flowing from the reference’s disclosure is unlikely to be productive of the result sought by the applicant. In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994). ANALYSIS Appellants argue that Migita explicitly teaches that the electrodes 7 (i.e., both electrodes) are disposed only in the recess portion 3 of the chuck 1, and are purposely not located near the second holding surface 4a (App. Br. 6). Appellants conclude that Migita teaches away from providing an electrode at the second holding surface 4a (i.e., a first electrode associated with the annulus as required by claim 1) (see id.). We agree with Appellants’ argument. Migita explicitly teaches that electrodes 7 may be disposed only on an area of the other main surface area 6 of the ceramic plate 2 which area corresponds to the recess-portion bottom surface used as the attraction region, but no electrostatic force from the second holding surface 4a is exerted to the wafer W (¶ [0064] (emphasis added)). This is so that residual attraction force can be quickly eliminated to be negligibly small once static electricity to the electrostatic attraction electrodes 7 is switched off and then the wafer forced to be bent to the recess portion is jerked back due to a resilient force of the wafer so as to quickly be removed from the chuck Appeal 2011-009056 Application 11/641,334 6 (id.). In other words, electrodes 7 may only be placed within the central disk area as shown in Figures 3A and 3B and cannot be placed at the holding surface 4a (i.e., at the annulus). Thus, clearly Migita teaches that both electrodes may only be placed at the central disk and no electrode can be placed at the annulus. Contrary to the Examiner’s assertion (Ans. 17), one skilled in the art, reading Migita, would be led in a direction divergent from the path that was taken by Appellants, and would not have been motivated to place an electrode at the annulus or holding surface 4a. See Gurley, 27 F.3d at 553. The additional references of Weldon, Hirayanagi, Brown, Os, Bates, Chung, and Carroll, either alone or in combination, do not remedy the above cited deficiency. Accordingly, we affirm the Examiner’s rejection of claim 1 and for the same reasons the rejections of claims 2-25. CONCLUSION The combination of Migita and Muka does not teach the limitations of: a first electrode associated with the annulus, wherein the first electrode is electrically connected to a first voltage potential; and a second electrode associated with the central disk, wherein the second electrode is electrically connected to a second voltage potential, and wherein the first electrode and second electrode are electrically isolated from one another as recited in independent claim 1. Appeal 2011-009056 Application 11/641,334 7 DECISION The Examiner’s decision rejecting claims 1-25 is reversed. 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)(iv) (2010). REVERSED babc