Citations
- 745 F. Supp. 2d 489
Full opinion text
MEMORANDUM OPINION
SUE L. ROBINSON, District Judge.
TABLE OF CONTENTS
I. INTRODUCTION.........................................................493
II. BACKGROUND...........................................................494
A. The Parties ...........................................................494
B. Technology Overview...................................................494
III. STANDARD..............................................................495
IV. DISCUSSION.............................................................495
A. The Bruel Patent......................................................495
1. Disclosure.........................................................495
2. Prosecution history.................................................496
3. Infringement: mono- and co-implantation..............................498
4. Written description: temperature limitations...........................499
5. Conclusion: the Bruel patent ........................................500
B. The Aspar Patents.....................................................501
1. Specification.......................................................501
2. The asserted claims.................................................502
3. Infringement: mono- and co-implantation..............................505
4. Validity...........................................................506
a. The '396 patent: certificate of correction..........................506
(1) Standard ..................................................506
(2) Discussion.................................................506
b. The '234 patent: indefiniteness...................................508
(1) Standard ..................................................508
(2) Discussion.................................................508
c. The '009 patent: claim construction in view of Bruel................509
(1) “Bridges”..................................................509
(2) “Mechanical forces”.........................................511
d. The'009 patent: anticipation by Bruel............................512
(1) Standard ..................................................512
(2) Discussion.................................................512
e. The '009 patent: obviousness in light of Bruel......................513
(1) Standard ..................................................513
(2) Discussion.................................................514
f. The '009 patent: anticipation by the '252 patent....................515
g. The '009 patent: written description..............................515
h. The '009 patent: best mode......................................516
5. Inequitable conduct.................................................517
a. Standard......................................................518
b. Facts.........................................................519
c. Discussion.....................................................521
6. Conclusion: the Aspar patents.......................................522
C. The '812 Patent........................................................523
1. Disclosure.........................................................523
2. Prosecution history.................................................524
3. Claim construction..................................................526
4. Validity...........................................................527
a. Enablement...................................................527
(1) Standard ..................................................527
(2) Discussion.................................................528
b. Obviousness...................................................529
5. Infringement ......................................................530
a. The accused products...........................................530
b. SOI/BESOI wafers.............................................532
c. “Bonded”/“On”.................................................532
d. Generally annular recess........................................534
6. Conclusion: the '812 patent..........................................535
V. CONCLUSION............................................................535
I. INTRODUCTION
Plaintiffs S.O.I.TEC Silicon On Insulator Technologies, S.A. (“Soitec”) and Commissariat á L’Énergie Atomique (“CEA”) (collectively, “plaintiffs”) filed their complaint against MEMC Electronic Materials Inc. (“MEMC” or “defendant”) on May 19, 2008, alleging infringement of U.S. Patents No. RE 39,484 (“the Bruel patent”), as well as U.S. Patent Nos. 6,809,009 (“the '009 patent”) and 7,067,396 (“the '396 patent”). (D.I. 1) In lieu of an answer, defendant moved to dismiss the complaint, which motion was denied by the court on February 20, 2009. (D.I. 16) Defendant thereafter answered and brought, inter alia, counterclaims for infringement of U.S. Patent No. 5,834,812 (“the '812 patent”), as well as for a declaration of noninfringement of several unasserted patents. (D.I. 19) Plaintiffs moved to dismiss defendant’s counterclaims relating to the unasserted patents but, subsequently, withdrew the motion. (D.I. 30, 48) Plaintiffs filed an amended complaint on July 21, 2009 adding a claim for infringement of U.S. Patent No. 7,498,234 (“the '234 patent”). (D.I. 57) The court granted defendant’s subsequent motion to bifurcate the issues of willfulness and damages for purposes of discovery and trial (D.I. 77), and denied plaintiffs’ cross-motion to bifurcate the issues of intervening rights and inequitable conduct (D.I. 85). Fact and expert discovery have now closed.
Currently before the court are ten motions for summary judgment. Defendant has moved for partial summary judgment of invalidity of the asserted claims of the '009, '396 and '234 patents (collectively, the “Aspar patents”) and for noninfringement of the Bruel and Aspar patents. (D.I. 187; D.I. 199) Plaintiffs have filed eight motions for summary judgment, seeking: (1) summary judgment of noninfringement of the '812 patent (D.I. 197); (2) summary judgment that the Bruel and Aspar patents satisfy the written description requirement (D.I. 202); (3) partial summary judgment that the certificate of correction issued for the '396 patent is valid (D.I. 204); (4) partial summary judgment that the Aspar patents are not unenforceable due to inequitable conduct (D.I. 206); (5) partial summary judgment that the Bruel patent does not anticipate the Aspar patents (D.I. 208); (6) partial summary judgment that the '812 patent is invalid for lack of enablement (D.I. 210); (7) partial summary judgment that the '812 patent is invalid in view of certain prior art (D.I. 212); and (8) partial summary judgment that the best mode requirement is satisfied for the claims of the '009 and '396 patents (D.I. 213). Also before the court are two motions in limine. (D.I. 141, 186) Oral argument was heard on September 3, 2010 and this matter is currently scheduled for trial commencing on October 25, 2010. The court has jurisdiction over these matters pursuant to 28 U.S.C. § 1338.
II. BACKGROUND
A. The Parties
Soitec is a French company and a leading developer of silicon-on-insulator semiconductor (“SOI”) wafers. CEA is the French Atomic Energy Commission, which operates a research facility known as the Laboratory of Electronics and Information Technologies in Grenoble, France. CEA is the owner of the '484 and Aspar patents, which are exclusively licensed to Soitec. MEMC is a Delaware corporation having a principal place of business in St. Peters, Missouri, and is also in the SOI business.
B. Technology Overview
Semiconductor films, also referred to as wafers, are a thin slice of semiconductor material, such as silicon crystal, used in the manufacture of microelectronic devices. Semiconductor wafers are made of nearly defect-free single crystalline material. Single-crystal silicon has been haled as one of the most important technological materials of the last decades.
SOI wafers contain three layers: a top, “active” layer of high-quality silicon (the “wafer”); a buried layer of electrically-insulating silicon dioxide (the “BOX” layer); and a silicon support layer (also called the “handle” or “handle wafer”). That is, two silicon wafer layers surround the BOX layer. The BOX layer is an electrical insulator; it keeps electrons flowing efficiently without letting stray electrons leak into the silicon substrate. As a result, junction capacitance (the electric charge temporarily stored where the regions meet) is reduced, electrons get to their destinations faster and device performance is increased. SOI wafers may perform with 30-40% less power input (with less error rate) than their bulk-silicon predecessors.
III. STANDARD
A court shall grant summary judgment only if “the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, if any, show that there is no genuine issue as to any material fact and that the moving party is entitled to judgment as a matter of law.” Fed.R.Civ.P. 56(c). The moving party bears the burden of proving that no genuine issue of material fact exists. See Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 586 n. 10, 106 S.Ct. 1348, 89 L.Ed.2d 538 (1986). “Facts that could alter the outcome are ‘material,’ and disputes are ‘genuine’ if evidence exists from which a rational person could conclude that the position of the person with the burden of proof on the disputed issue is correct.” Horowitz v. Fed. Kemper Life Assurance Co., 57 F.3d 300, 302 n. 1 (3d Cir.1995) (internal citations omitted). If the moving party has demonstrated an absence of material fact, the nonmoving party then “must come forward with ‘specific facts showing that there is a genuine issue for trial.’ ” Matsushita, 475 U.S. at 587, 106 S.Ct. 1348 (quoting Fed.R.Civ.P. 56(e)). The court will “view the underlying facts and all reasonable inferences therefrom in the light most favorable to the party opposing the motion.” Pa. Coal Ass’n v. Babbitt, 63 F.3d 231, 236 (3d Cir.1995). The mere existence of some evidence in support of the nonmoving party, however, will not be sufficient for denial of a motion for summary judgment; there must be enough evidence to enable a jury reasonably to find for the nonmoving party on that issue. See Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 249, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986). If the nonmoving party fails to make a sufficient showing on an essential element of its case with respect to which it has the burden of proof, the moving party is entitled to judgment as a matter of law. See Celotex Corp. v. Catrett, 477 U.S. 317, 322, 106 S.Ct. 2548, 91 L.Ed.2d 265 (1986).
IV. DISCUSSION
A. The Bruel Patent
1. Disclosure
There are several methods for producing SOI wafers. For example, as described in the Bruel patent, silicon crystal films may be grown on a monocrystalline substrate (“heteroepitaxy” methods). (Bruel patent, col. 1:25-29) Another method for forming a monocrystalline film is by an oxygen ion implant of the wafer followed by thermal treatment (often referred to as “SIMOX”). (Id., col. 1:30-34) “Other processes make use of the principle of thinning a wafer by chemical or mechanical abrasion.” (Id. at col. 1:35^5) One common such process is known as “etch-stop,” whereby the thinning of a wafer is controlled by a chemical process based on the different etching potentials of n-type and p-type silicon layers in etching solutions. (Id.)
The Bruel patent describes several disadvantages to these common methods. For example, heteroepitaxy methods are limited by the nature of the substrates, which are also expensive and fragile. (Id., col. 1:55-60) The high dose ion implantation of the SIMOX method is performed on complex implantation machines with limited output. (Id., col. 1:62-65) Etch-stop “makes the process complex and in certain cases can limit the use of the film,” for example, where it is produced by p-type doping, the electronic device would have to adapt to the p-type nature of the film. (Id., col. 1:66-col. 2:6)
The Bruel process avoids these stated disadvantages, and consists of three distinct stages. The first step is implantation by bombardment, whereby a layer of gaseous microbubbles (defining in the volume of the wafer an upper and lower area that will eventually be separated) is forced into the silicon substrate. (Id., col. 2:26-37) This preferably occurs at an implantation temperature between 20° and 450° C. (Id. at col. 3:9-19) Coalescence of the micro-bubbles in this layer, along with crystalline rearrangement, ultimately causes separation between the film and substrate during the third process stage of heat treatment. (Id. at col. 3:20-26) In the second stage, a stiffener having at least one rigid layer is contacted to the face of the wafer. (Id. at col. 2:38-40) The stiffener compensates for the stresses produced by the microbubbles occurring during the final heat treatment phase, which would otherwise cause surface deformation and blistering. (Id. at col. 3:27-43) Accordingly, the stiffener cannot be incorporated at a temperature that would trigger the third stage procedures. (Id. at col. 4:19-21) In the third, heat treatment stage, the wafer (with stiffener) undergoes a thermal treatment at a temperature sufficient to cause crystalline rearrangement and coalescence of the micro-bubbles (above approximately 500° C), i.e., separation of the film and substrate. (Id., col. 4:22-31)
2. Prosecution history
The Bruel patent is a reissue patent. U.S. Patent No. 5,374,564 (“the '564 patent”) was issued by the PTO on December 20, 1994. The '564 patent claimed a process for the preparation of thin semiconductor films comprising a first implantation stage involving “ion bombardment,” the “ions being chosen from among hydrogen gas ions or rare gas ions,” a second contacting step and a third, thermal treatment step. In 1999, Soitec sued Silicon Genesis (“SiGen ”) for infringement of the '564 patent (hereinafter, the “SiGen ” litigation); the jury found all but one asserted claim of the '564 invalid as not enabled with respect to the implantation step. Specifically, the '564 patent taught only implantation of hydrogen ions, not additionally the rare earth gas ions (helium, neon, argon, krypton and xenon) claimed. The Federal Circuit affirmed, stating that the jury had before it substantial evidence that “hydrogen ions are significantly different than other rare earth gases in mass, bonding capability and diffusion characteristics” and, therefore, Soitec’s disclosure enabling only hydrogen was insufficient. See Soitec, S.A. v. Silicon Genesis Corp., 81 Fed.Appx. 734, 738-39 (Fed.Cir.2003) (unpublished).
In May 2003, CEA filed reissue proceedings, adding nineteen (19) new claims for consideration. Several such new claims, and subsequent amendments to existing claims, were drawn to a first implantation stage by hydrogen or helium ions. (JA-1688-89; JA-1787-96) The examiner issued a § 251 rejection, as follows:
Regarding claims 1-3, 5-15, 22, 33-38, 40 and 41-44, the claims are broadening because of the newly added limitations requiring implantation of “a combination of hydrogen gas ions and rare gas ions” (claims 1, 11-14, and 41) or “hydrogen ions in combination with rare gas ions” (claims 22 and 40) or “hydrogen and helium ion bombardment” (claim 33). These features are broadening because they contain within their scope any conceivable product or process — i.e. implantation of the combination of hydrogen and rare gas ions — which would have infringed the original patent because hydrogen is implanted. Alternatively, in the context of the claims, the implantation of the combination of hydrogen and rare gas ions would infringe the reissue claim, but not infringe the original patent because the original patent claim 1 implants hydrogen gas ions or rare gas ions. The remaining [dependant] claims are [also] rejected[.]
(JA-1843) An enablement rejection was also entered, stating:
[The foregoing claims are also] rejected ... as failing to comply with the enablement requirement. The claims contain subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention ... [T]he claims lack enablement because the disclosure fails to provide an enabling basis for practicing the invention with rare gas ions alone (i.e. implantation of helium in claims 27-32) or in combination with hydrogen (claims 1-3, 5-15, 22, 33-38, 40 and 41-44).
(JA-1844-45) The examiner further noted the unpredictability of the chemical arts and that compliance with the enablement requirement is most important in this area of technology. (JA-1845)
In response, the applicants argued that the specification enabled implanting hydrogen in combination with helium or other gas ions by disclosing that,
[i]n the performance of the process according to the invention, the ions used for implantation by bombardment are usually H+ ions, but this choice must not be looked upon as limitative. Thus, the principle of the method is applicable with molecular hydrogen ions or with ions of rare gases such as helium, neon, krypton and xenon, used either sparingly or in combination.
(JA-1877-81) (citing '564 patent, col. 4:38-44) Given this disclosure, as well as the “extensive literature on rare gas implantation of semiconductors and metals, the applicant assert[ed] that one skilled in the art could have made the necessary adjustments based on routine experimentation to practice the invention using any one or all of the recited gas ions as of the '564 patent filing date.” (JA-1879) The examiner disagreed, and issued a rejection on enablement based on res judicata in view of the Federal Circuit’s SiGen decision. (JA-2181-85) (“[A] reissue application is not the proper forum in which to submit different evidence regarding rare gases implantation that could have been submitted and considered during litigation.”)
In response, the applicants cancelled some claims, added sixty (60) new claims, and narrowed all pending claims to mono-implantation of hydrogen; language encompassing co-implantation of hydrogen and helium (or other rare gas ions) was removed. (JA-2199-2235) A notice of allowability was thereafter issued in which the examiner noted that “the applicant has amended the claims to pertain to only hydrogen and the claims no longer include rare gas ions (which was held to be invalid by the Federal Circuit Court of Appeals). Therefore, the applicant has narrowed the scope of all claims and no broadening has occurred.” (JA-2368) (emphasis in original) A third-party protestor thereafter argued that the claims should be limited to “consisting” (rather than “comprising”) to prevent any future broadening attempts. (JA-2293-97) The examiner disagreed that such amendment was necessary:
Prosecution history estoppel (file wrapper estoppel), collateral estoppel and res judicata all function to make clear that the applicant’s claims are limited to hydrogen ions. Due to these doctrines and the current application’s well-established record, the examiner does not believe that any further amendments are necessary on behalf of the applicant to further clarify this resolved issue.
(JA-2370) (emphasis in original) The Bruel (reissue) patent issued on February 6, 2007. Michel Bruel (“Bruel”) is the sole named inventor.
3. Infringement: mono- and co-implantation
The foregoing prosecution history informs the court’s determination that the claims of the Bruel patent must be limited to hydrogen ions. Remarkably, it is Soitec’s position that the claims include the referenced hydrogen ion bombardment, but may also include additional steps of bombardment with other gases, evidenced by the use of the term “comprising.” This is precisely the situation envisioned by the third party protestor, leading the foregoing comments by the examiner. The “ions” versus “hydrogen ions” issue has been thoroughly vetted before the PTO (and, in the context of the Bruel patent, presented to the Federal Circuit). Soitec’s arguments at bar strain credulity. See, e.g., Computer Docking Station Corp. v. Dell, Inc., 519 F.3d 1366, 1379 (Fed.Cir. 2008) (plaintiffs “cannot recapture claim scope disavowed during prosecution”); Bd. of Regents of the Univ. of Texas Sys. v. BENQ Am. Corp., 533 F.3d 1362, 1373 (Fed.Cir.2008) (plaintiffs “cannot rely on the word ‘comprising’ to broaden the scope of a claim phrase that was limited during prosecution so as to gain allowance of the patent.”).
Since the Bruel patent claims may not be interpreted as covering more than the mono-implantation of hydrogen ions, the court finds that MEMC’s current manufacturing process cannot infringe asserted claim 50. The parties do not dispute that MEMC implants its wafers first with helium, then with hydrogen ions during the layer transfer process, as depicted in the following diagram. (D.I. 250 at 9)
(MA-0209) Soitec disputes whether this one-after-another technique is truly a “co-implant” (id.), but infringement in this case does not turn on such classifications. MEMC’s process is not limited to hydrogen implantation and, therefore, it is outside the scope of the Bruel patent claims. In view of the court’s holding, the court need not separately evaluate whether MEMC’s “low-temperature” (room temperature corresponding to the second stage of claim 50, or 350° C or less for the third stage) process parameters meet the remaining limitations.
4. Written description: temperature limitations
Soitec moves for partial summary judgment that the Bruel patent satisfies the written description requirement of 35 U.S.C. § 112. (D.I. 202) It is MEMC’s position that the Bruel patent unequivocally identifies 500° C as the minimum temperature required for the third stage when the implanted substrate is silicon. (D.I. 243 at 7) MEMC, therefore, asserts that, given this teaching and the lack of any examples of practicing the claimed process at a temperature under 500° C, one of ordinary skill in the art would understand that Bruel did not possess a process using thermal treatments below 500° C as of the priority date. (Id.) The issue is one of claim construction.
Soitec asserts that claim 50 of the Bruel patent, specifically, the “thermally treating ... at a temperature ... adequate to create by a crystalline rearrangement effect in the wafer and a pressure effect in the hydrogen microbubbles” limitation correlating to the third stage, should be construed to cover “any third stage temperature that allows for crystalline rearrangement and coalescence of the bubbles.” (D.I. 155 at 2; D.I. 203 at 11) In support for limiting the claims to “at least 500° C” for the third stage, MEMC points to the specification, which states that the
heat treatment must, according to the invention, be carried out at a temperature at which the crystalline rearrangement and coalescence of the microbubbles can effectively take place. For example, in the case of silicon, a temperature above approximately 500° C is necessary!.]
(Bruel patent, col. 4:24-29) (emphasis added) During prosecution of the '564 patent, Bruel provided a declaration by Dr. Kevin S. Jones, a Ph.D. in Materials Science and Engineering, stating that “one could begin the annealing study in the 500° C-700° C range where atomic motion in silicon is often observed to begin.” (MA-1283-84) In the later-filed Aspar patents, Bruel (and the other named inventors of the Aspar patents) stated that, for the third step, “[t]his temperature is, for example!,] 500° C for silicon.” ('009 patent, col. 1:53-54) MEMC does not point to any statements made during the reissue proceedings that may bear on this issue. (D.I. 167 at 15-18)
The court finds the foregoing insufficient to limit claim 50 to “at least 500° C” for the third stage. (D.I. 155) There is no temperature limitation in the claims. There is no. clear and unmistakable disclaimer of claim scope of record. See Cordis Corp. v. Boston Scientific Corp., 561 F.3d 1319, 1329 (Fed.Cir.2009). “[A]bsent a clear disclaimer of particular subject matter, the fact that the inventor may have anticipated that the invention would be used in a particular way does not mean that the scope of the invention is limited to that context.” Martek Biosciences Corp. v. Nutrinova, Inc., 579 F.3d 1363, 1382 (Fed. Cir.2009) (citations omitted). Although MEMC argues that Bruel did not have possession of a process comprising a third stage temperature of below 500° C, MEMC does not point to expert testimony that third stage treatments below 500° C would not have been known to a person of ordinary skill in the art (or discernable to such a person without undue experimentation). See Martek, 579 F.3d at 1378. Under the circumstances at bar, the court applies the general rule that particular embodiments appearing in the specification will not be read into the claims. Having rejected MEMC’s claim construction, Soitec’s motion for partial summary judgment that claim 50 of the Bruel patent is not invalid for lack of written description is granted.
5. Conclusion: the Bruel patent
To summarize: (1) MEMC’s motion for summary judgment of noninfringement (D.I. 199) is granted with respect to the Bruel patent; and (2) Soitec’s motion that the patents in suit satisfy the written description requirement (D.I. 202) is also granted with respect to the Bruel patent. The court proceeds to discuss the pending motions relating to the Aspar patents.
B. The Aspar Patents
The Aspar patents are entitled “Method for producing a thin layer of semiconductor material” and name Bruel, Bernard Aspar (“Aspar”), and Thierry Poumeyrol (“Poumeyrol”) as inventors. The Aspar patents share a common specification and are related continuation applications in a chain. The first United States patent in the Aspar patent family is U.S. Patent No. 6,020,252 (“the '252 patent”), which was filed on May 14, 1997 and issued February 1, 2000. The '252 patent describes processes for producing a thin layer of semiconductor material by (1) implanting (2) hydrogen or rare gas ions (3) into a semiconductor material substrate. Claims are drawn to subjecting a semiconductor wafer to “implantation” by bombardment by “ions of a rare gas or hydrogen.”
A continuation application (No. 09/299,-683) was filed claiming priority to the '252 application on April 26, 1999, which eventually matured into U.S. Patent No. 6,225,-192 (“the '192 patent”). The '192 patent similarly claims a method of producing a thin layer of semiconductor material by subjecting a wafer to implantation with “a rare gas or hydrogen,” subjecting it to a thermal treatment, and then applying a mechanical energy to separate regions.
The '009 patent was filed on February 6, 2001 as a continuation from the '192 patent; it issued October 26, 2004. The '396 patent was filed as a continuation from the '009 patent application, filed February 23, 2004, and issued June 27, 2006. The '234 patent was filed as a continuation of the '396 patent application on January 9, 2006, and issued March 3, 2009. As continuations, the Aspar patents share a common specification that describes a method for forming thin-layer SOI films.
1. Specification
The invention provided in the Aspar patents is stated to be an improvement over the process of the '564 patent. As is the case with most improvement patents, there is overlap between the '564 patent and the Aspar patents. For example, both describe a first ion bombardment phase sufficient to create microcavities. The '564 patent disclosed an implant temperature of lower than 500° C, preferably within the 20°-450° C range for silicon. (Bruel patent, col. 3:9-19) The Aspar patents provide that, in the case of implantation of hydrogen ions in silicon, “the implantation will be carried out at a temperature below 350° C.” (Id., col. 4:47-49) It is a most “important feature” of the Aspar patents’ invention that the implantation step occurs at a dose and temperature insufficient to cause separation. (Id., col. 4:7-17; 4:43^16; 4:50-60)
After the ion implantation step in Bruel, a stiffener is attached to the face surface. A stiffener (or “support”) is attached only optionally in the Aspar process, and this occurs after the second Aspar process step — -an intermediate thermal treatment step. ('009 patent, col. 3:41-56) This intermediate thermal treatment step is necessary because, at the temperature of the final heat treatment stage of Bruel, undesirable blisters and craters form in the surface of the silicon wafer. (Id., col. 2:13-33) The creation of electronic circuits in or at the wafer surface “implies the carrying out of certain classic micro-electronics operations ... that require thermal treatment stages (typically from 400° C to 700° Q” at which temperature the blisters form. (Id.) These surface defects render it difficult to bring the flat face of the wafer with the support so as to detach the semiconductor layer from the rest of the wafer. (Id.)
The Aspar patents provide for an intermediate step between ion implantation and separation, whereby “the part of the wafer corresponding to the future thin layer [is thermally treated,] in particular between 400° C and 700° C for silicon, without degrading the surface condition of the flat face of the wafer and without separation of the thin layer.” (Id., col. 2:36-41) This intermediate step occurs “at a temperature that is sufficient to allow coalesce of the microcavities along the reference plane,” for example, 550° C if the ion implantation step occurred at 350° C. (Id., col. 5:1-14; fig. 2) This allows for the optional step of providing an electronic component on the wafer before the thin layer is formed. (Id, col. 2:41^3; 3:41-45; fig. 3) Bruel, by contrast, “does not allow the production of electronic circuits in or at the surface of the flat face of the wafer after the ion implantation step.” (Id, col. 1:19-54; col. 2:5-10)
The “thermal treatment” step of Bruel, whereby the wafer with stiffener attached are subjected to temperatures (above approximately 500° C) to achieve the crystalline rearrangement resulting in separation, corresponds to the final “separation step” disclosed by the Aspar patents. This third step consists of separating the wafer into two parts by “the application of mechanical forces between the two parts of the wafer.” (Id., col. 3:5-9) Put another way, because of the intermediate thermal step, whereby only partial separation occurs between the wafers allowing for the possible incorporation of electronics, “the separation requires an extra step of applying mechanical forces.” (Id, col. 3:34-35) The separation step “consists of applying separating mechanical forces, for example, tensile forces between the parts of the wafer or substrate situated on each side of the reference plane in a manner that fractures the remaining solid bridges” between wafer segments and between the microbubbles. (Id, col. 5:51-55; fig. 4) As noted above, it is preferable to affix the wafer to a “support or applicator” (e.g., stiffener) prior to this step, “through which mechanical [separation] forces such as tensile and/or shearing forces will be applied.” (Id, col. 3:49-53; 6:3-10)
2. The asserted claims
The court’s discussion of the scope of the claims at issue is best framed by a brief discussion of the prosecution history. The application that matured into the '009 patent, U.S. Patent Application No. 09/777,516 (“the '516 application”), contained original claims drawn to a process comprising “introducing ions into the first substrate.” (MA-1010-12) On September 23, 2003, PTO Examiner George Fourson rejected the claims for lack of enablement. (MA-0934) On February 23, 2004, the applicants narrowed the claims to “introducing hydrogen ions,” and the application was thereafter allowed (on May 25, 2004). (MA-0937)
Claim 1 of the '009 patent claims
1. A method for producing a thin film comprising:
providing a first substrate having a face surface;
introducing hydrogen ions into the first substrate at the face surface, such that microcavities are formed in the first substrate during or after introducing the ions, wherein the microcavities define a thin film layer extending from the first surface to the microcavities, the micro-cavities reside between solid bridges of the first substrate, and the hydrogen ions are introduced into the first substrate at a temperature and at a total amount so as not to fracture the solid bridges during energizing of the first substrate; bonding a second substrate to the face surface of the first substrate; and applying mechanical forces to fracture the solid bridges.
('009 patent, claim 1) Claim 4 is asserted by Soitec against MEMO, which depends from claim 2 (further depending from claim 1) and additionally requires applying energy to the first substrate after introducing hydrogen ions.
On February 23, 2004, the same day the '009 patent claims were narrowed to hydrogen ions prior to allowance, the applicants filed U.S. Application No. 10/784,601 (“the '601 application”) as a continuation of the '516 application; the '601 application was also assigned to Examiner Fourson. The '601 application would later issue as the '396 patent. As filed, the '601 application claimed a process including “an ion implantation step consisting of bombarding said flat face [of the wafer] with ions chosen from among the ions of rare gases or of hydrogen.” (JA-0293) Claims 1 to 12 were then pending. A preliminary amendment was commensurately filed cancelling claims 1 to 12 and adding new claims 13 to 20, drawn to a process comprising “introducing ions into the first substrate.” (JA-0328-29; JA-405-06)
It appears as though a rendition of the pending claims in the '601 application, as well as a list of the claims in the copending '516 application, were concurrently faxed to Examiner Fourson on June 3, 2004 and included in the '601 application file wrapper. In the '601 application file, with a fax header dated June 3, 2004, appears a copy of the February 23, 2004 preliminary amendment (in the '601 application) as well as several pages of claims from the '516 application, which had been allowed on May 25, 2004. (JA-0408-10) This claim listing from the '516 application contained claims 13 to 28 (sixteen claims). The pages correlate to an amendment filed in the '516 application on February 25, 2004, accompanying a request for continued examination, in response to a final rejection by Examiner Fourson in that case. (Compare JA-0155-57 with JA-0408-10) In that amendment, the independent claims of the '516 application were amended to add, inter alia, the “hydrogen ion” limitation. For example,
(JA-0408)
In September 2005, having not received a first action on the merits in the '601 application, the applicants filed a status request with the PTO. (JA-0467) On September 22, 2005, a Notice of Allowability of claims “13 to 28” was issued. (JA-0498) The examiner’s reasons for allowance stated that the application was allowable “for the reasons stated in the parent application [the '516 application, then issued as the '009 patent] and because the prior art taken alone or in combination is not seen to disclose or suggest implantation parameters sufficient to form the microcavities having the recited properties. Also, claims 23 and 27 are seen to recite a dose between 1 x 1016 and 4 x 1016 ions/cm ~2.” (JA-0499)
The claims pending in the '601 application at the time the application was allowed (September 22, 2005) were as reflected by the preliminary amendment dated February 23, 2004: claims 13 to 20, with independent claim 13 reading as follows.
On October 11, 2005, the applicants sent a “request for clarification of [the] notice of allowability” noting that claims “13 to 28” had been allowed, but only claims “13 to 20” are pending in the application; similarly, the examiner’s reference to claims 23 and 27 “is confusing.” (JA-0506) On December 20, 1995, the applicants filed an amendment after the notice of allowance pursuant to Rule 312. The amendment referred to claims 1-12 as cancelled, provided pending claims 13-20, and presented an amendment to independent claim 13 only. Specifically, the claim was changed from reading “wherein the microcavities define a thin film layer extending from the first surface to the microcavities” to now read, “extending from the face surface.” (JA-0509) The pending claims remained drawn to an ion implantation step whereby “ions” are introduced to the first substrate at the face surface. (Id.)
The issue fee was paid, and the examiner thereafter entered the applicants’ amendment on January 18, 2006. (JA-0513) Another status request was filed by the applicants on April 27, 2006. (JA-0516) In May 2006, the examiner sent a status letter stating that the application “was forward[ed] to TC to have an amendment entered[;] the application will be re-forwarded back to publication] after the amendment has been entered in the application.” (JA-0517)
The '601 application issued as the '396 patent on June 27, 2006. Sixteen claims are printed on the face of the '396 patent, which claims correlate to (formerly pending) claims 13 to 28 of the '516 application. On October 30, 2006, the applicants filed a “petition for certificate of correction” which the applicants stated was “required to correct significant printing errors” in the '396 patent. (JA-0519-20) By that certificate of correction, which was duly entered by the PTO, the following changes to the claims of the '396 patent were effectuated: (1) claims 9-16 were deleted entirely; (2) “hydrogen” was deleted from independent claims 1 and 8; and (3) the “temperature and total amount” limitation was also deleted. The claims of the '396 patent were effectively transformed to originally-pending claims 13 to 20 of the '601 application.
Claim 1 of the '396 patent reads, as corrected:
1. A method for producing a thin film comprising:
providing a first substrate having a face surface;
introducing ions into the first substrate at the face surface, such that microcavities are formed in the first substrate during or after introducing the ions, wherein the microcavities define a thin film layer extending from the face surface to the microcavities, and wherein the microcavities reside between solid bridges of the first substrate; bonding a second substrate to the face surface of the first substrate; and applying mechanical forces to fracture the solid bridges.
Claim 4 is asserted by Soitec as infringed by MEMC, which depends from claim 2 (further depending from claim 1) and contains the additional limitation that energy is applied to the first substrate after the introduction of ions.
The prosecution history of the '234 patent is unremarkable for the purposes of the motions at bar. Claim 24 is asserted by Soitec, which depends from claim 21, reading:
21. A method for producing a thin film comprising the steps of: implanting hydrogen ions into a semiconductor material substrate through a face thereof so as to form a layer of microcavities with bridges connecting a thin film layer of desired thickness to a remaining portion of the semiconductor material substrate, the quantity of ions in the layer of microcavities being insufficient to produce fracture of the bridges throughout the layer of microcavities by a subsequent thermal annealing alone; conducting a subsequent thermal annealing of the semiconductor material substrate at sufficiently low temperature to substantially limit diffusion of gas from the semiconductor material substrate; and effecting the propagation of bridge fracture to sever the thin film layer from the remaining portion of the semiconductor material substrate through the application of an additional mechanical force.
Claim 24 adds an additional limitation that effecting the propagation of bridge fracture comprises a process carried out after thermal annealing of the semiconductor material substrate.
3. Infringement: mono- and co-implantation
MEMC moves for summary judgment of noninfringement with respect to the Aspar patents. (D.I. 199) As discussed previously in the context of the Bruel patent, MEMC employs a helium implant prior to a hydrogen implant in its process. The claims of the '009 patent were narrowed to hydrogen atoms in response to an enablement rejection. (MA-0934; MA-0937) As such, the broader subject matter was surrendered and MEMC cannot infringe. Prosecution history estoppel precludes Soitec from arguing that MEMC infringes claim 24 of the '234 patent under the doctrine of equivalents. See Festo Corp., 535 U.S. at 736-37, 122 S.Ct. 1831.
4. Validity
MEMO has moved for summary judgment of invalidity of each of the asserted Aspar patent claims. The court addresses MEMC’s arguments in turn.
a. The '396 patent: certificate of correction
The court takes up the issue of the validity of the '396 patent on cross-motions: Soitec moves for partial summary judgment that the certificate of correction for the '396 patent is valid (D.I. 204); and MEMO moves for summary judgment of invalidity on the same ground (D.I. 187).
(1) Standard
Two statutory sections govern certificates of correction, 35 U.S.C. §§ 254 and 255. Section 254 controls in situations where the PTO has made a mistake. This case presents a question of review with respect to an applicant-initiated certificate of correction which is addressed by section 255, governing mistakes by the applicant:
Whenever a mistake of a clerical or typographical nature, or of minor character, which was not the fault of the Patent and Trademark Office, appears in a patent and a showing has been made that such mistake occurred in good faith, the Director may, upon payment of the required fee, issue a certificate of correction, if the correction does not involve such changes in the patent as would constitute new matter or would require re-examination.
35 U.S.C. § 255 (emphasis added).
The Federal Circuit has stated that, in order to invalidate a certificate of correction for impermissible broadening, proof of two elements must be present: “(1) the corrected claims are broader than the original claims; and (2) the presence of the clerical or typographical error, or how to correct that error, is not clearly evident to one of skill in the art.” See Central Admixture Pharm. Svcs., Inc. v. Adv. Cardiac Solutions, P.C., 482 F.3d 1347, 1353-54 (Fed.Cir.2007) (emphasis added). The first element, a claim construction issue, is a question of law. Id. (citations omitted). “The second element, whether the error and its correction would both be clearly evident to one of skill in the art, has been treated as a factual question.” Id. (collecting authority).
The Federal Circuit has further enumerated three categories into which an error may fall: (1) “mistakes [that] are immediately apparent and leave no doubt as to what the mistake is,” such as a blatant misspelling; (2) “those typographical mistakes not apparent to the reader at all; for example, a mistake resulting in another word that is spelled correctly and that reads logically in the context of the sentence;” and (3) “where it is apparent that a mistake has been made, but it is unclear what the mistake is.” Superior Fireplace Co. v. Majestic Prods. Co., 270 F.3d 1358, 1370 (Fed.Cir.2001). Section 255 does not preclude broadening corrections so long as they are corrections of clerical or typographical mistakes and “only where it is clearly evident from the specification, drawings, and prosecution history how the error should appropriately be corrected.” Id. at 1372. Put another way, the public must be provided with notice as to the scope of the claims. Id.
(2) Discussion
The certificate of correction broadened the as-printed claims. There can be no doubt that “ions” is broader than “hydrogen ions;” the corrected claim, as a matter of law, “covers territory the old [claim] did not.” Central Admixture Pharm. Svcs., 482 F.3d at 1353. The certificate of correction is valid, therefore, only if it effectuated the “clearly evident” solution, as perceived by a person of ordinary skill in the art, to a clerical or typographical mistake. Superior Fireplace, 270 F.3d at 1373.
The threshold inquiry, however, is whether the misprinting of claims was a clerical or typographical mistake capable of correction under § 255 in the first instance. Neither party claims that a simple printing error occurred. Soitec argues that Examiner Fourson intentionally issued the same overly broad claims in the '396 patent that he had previously rejected in the parent case; MEMO claims that Examiner Fourson actually “examined a different set of claims than the applicant actually wanted,” which miscommunication was caused by the applicant’s June 3, 2004 fax. (D.I. 244 at 14)
The court notes at this juncture that both parties’ positions are predicated on unverifiable facts. Examiner Fourson cannot testify as to his intentions. Ultimately, the fact-finder has no tools to determine the precise error that occurred. Yet the court must ultimately resolve the issue of whether a “clear” solution to this cause-less problem exists in this case. MEMC’s proffered patent law expert can offer nothing but speculation as to what actually occurred during the prosecution of the '516 and '601 applications or as to Examiner Fourson’s state of mind. There is nothing to suggest that the mistake that occurred was of a “minor character,” as both parties recognize that the scope of the pending (and issuing) claims was changed; the argument is over whether this was intended to be the case. Section 255, therefore, is inapplicable, and the certificate of correction for the '396 patent is invalid.
Even if the correction was of a mistake of minor character, the court need not determine the sufficiency of MEMC’s evidence on the second, factual component of the test. If the certificate of correction for the '396 patent is valid, the patent claims are invalid as non-enabled pursuant to the Federal Circuit’s prior SiGen decision, 81 Fed.Appx. at 738-39. If the certificate of correction for the '396 patent is invalid, the '396 patent claims would be invalid as anticipated by the '009 patent claims. The court need not expend further its limited resources on the issue, nor is a jury required to determine the propriety of the correction made.
That Soitec elected to bring suit on the '396 patent, with the state of its record in disarray and validity highly questionable, is remarkable, bordering on frivolous. Its motion is denied; the '396 patent is invalid.
b. The '234 patent: indefiniteness
MEMO moves for summary judgment that claim 24 of the '234 patent is invalid for indefiniteness. (D.I. 187) There is no cross-motion by Soitec.
(1) Standard
The definiteness requirement is rooted in § 112, ¶ 2, which provides that “the specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.” “A determination of claim indefiniteness is a legal conclusion that is drawn from the court’s performance of its duty as the construer of patent claims.” Personalized Media Comm., LLC v. Int’l Trade Com’n, 161 F.3d 696, 705 (Fed.Cir.1998).
Determining whether a claim is definite requires an analysis of whether one skilled in the art would understand the bounds of the claim when read in light of the specification ... If the claims read in light of the specification reasonably apprise those skilled in the art of the scope of the invention, § 112 demands no more.
Id. (citing Miles Lab., Inc. v. Shandon, Inc., 997 F.2d 870, 875 (Fed.Cir.1993)).
(2) Discussion
Claim 24 of the '234 patent depends from claim 21, which recites in relevant part: “conducting a subsequent thermal annealing of the semiconductor material substrate at sufficiently low temperature to substantially limit diffusion of gas from the semiconductor material substrate.” No mention of a specific time, temperature, or gas is made in the claim.
The court’s task in determining whether the foregoing functional limitation is sufficiently definite “is a difficult one that is highly dependent on context.” Halliburton Energy Servs., Inc. v. M-I LLC, 514 F.3d 1244, 1255 (Fed.Cir.2008). The context here is, as Examiner Fourson noted, a highly unpredictable chemical art. (JA-1845) The Aspar patents themselves claim as their inventive features small process modifications (such as an intermediate heating) that result in tremendous differences. The court concludes that the applicants did not use “reasonably precise” terms to describe the invention of claim 24 in light of the subject matter. See Exxon Research and Engineering Co. v. U.S., 265 F.3d 1371, 1379 (Fed.Cir.2001) (citing Orthokinetics, Inc. v. Safety Travel Chairs, Inc., 806 F.2d 1565, 1576 (Fed.Cir.1986)).
The parties provide little extrinsic evidence to assist in the court’s construction. See id. at 1376. Soitec relies on test results obtained from its litigation expert who completed a post-anneal analysis of the amount of hydrogen present in MEMC’s wafers. (D.I. 247 at 15-16) Even assuming that these post-anneal tests (1) are accurate and (2) did not destroy the substrate (as MEMC suggests), this technique does not appear in the Aspar patents, and cannot be used to satisfy § 112. Soitec has not pointed to, and the court has not discerned, any portion of the As-par patents’ specification describing measuring the amount of hydrogen diffusing prior to, or during, the thermal annealing.
Soitec does not explain what a “sufficiently low temperature” is for purposes of the claims. Focusing on the “substantially limit the diffusion of gas” term, Soitec states that “substantially” is defined by the maximum temperature noted for all of the “various phases of the method,” or 900° C. (See '009 patent, col. 5:46) Soitec also states that one skilled in the art would understand, based on the specification, that diffusion must be limited such that the amount of implant material retained in the wafer would be sufficient to permit “embrittlement” to take place during the thermal treatment. (D.I. 247 at 17) Soitec does not point to any extrinsic evidence in this regard. MEMO points to deposition testimony by Bruel, stating that he did not know the difference between the temperature at which helium and hydrogen would diffuse within the silicon lattice. (MA-0875-76 at 208-09) (“I even don’t know if all the mechanism[s] are well known. Because diffusion is also something which is not as simple we should like it is [sic].”)
As an initial matter, the “900° C” maximum temperature of the process of the invention says nothing about the “sufficiently low temperature” limitation at issue — no lower boundary is provided. The specification provides only that the wafer embrittles, but separation does not occur, at the appropriate temperature and diffusion rate. ('234 patent, col. 3:35-38) Notwithstanding that the claim is not specific as to what “gas” diffuses from the wafer, there is no disclosure how diffusion of free gas from the wafer is to be measured, before or after the annealing. As Bruel’s testimony indicates, diffusion is not a phenomenon that occurs uniformly with respect to all gases. There is no indication of how much diffusion is too much. The specification provides that diffusion should be limited so that bridge fracture does not occur, but essentially “teaches those skilled in the art [ ] to experiment and find out for themselves” the proper balance of temperature and diffusion for the exuded gas. See Exxon Research and Engineering Co., 265 F.3d at 1379 (quoting In re Jolly, 36 CCPA 825, 172 F.2d 566, 569 (1949)). The court has no compelling extrinsic evidence before it indicating otherwise. For these reasons, the court finds that claim 24 of the '234 patent is not amenable to construction and is, therefore, indefinite as a matter of law. MEMC’s motion is granted in this regard. (D.I. 187)
c. The '009 patent: claim construction in view of Bruel
(1) “Bridges”
MEMO argues that Soitec’s proposed claim constructions eliminate the patentable distinctions of the Aspar patents over the '564 patent. The first limitation at issue in this regard is “bridges,” which MEMO asserts must be construed to mean “bridges that are stable enough to avoid blistering of the implanted surface in the absence of a stiffener when exposed to the 400-700° C thermal treatments of electronic circuit production.” (D.1.189 at 9) (citation omitted) Specifically, the parties’ proposals on this term are as follows:
It is MEMC’s position that, if Soitec’s broad claim constructions are adopted, such as that proposed for “bridges,” the distinctions between the '564 and Aspar patents will be nullified.
At this juncture, the court notes that the Aspar patents utilize broad and conditional language throughout the specification. For example: a thin layer “can possibly be provided with” electronic components (’009 patent, col. 1:11); electronic circuits “can be completely or in part created in these layers” (id., col. 1:17); the inventions “allows” one to carry out a thermal treatment step without degrading surface condition (id., col. 2:36); and the intermediate thermal treatment “can form” part of the operations for developing electronic components (id. at col. 2:41). Yet the crux of the invention is to provide, by a thermal treatment step, microcavities and bridges. These microcavities and bridges are described as being in a “stable state,” such that electronic components can be produced in the wafer before the formation of the thin layer. (Id., col. 3:21-26; col. 3:41-45) This stability also necessitates “an extra step of applying mechanical forces” to separate the layers. (Id., col. 3:34-35)
During prosecution of the '009 patent, the examiner rejected the claims on the ground that the specification does not “reasonably provide enablement for recitation of [the] formation of microcavities broadly.” (JA-0085) In response, the applicants noted that they “are not claiming the formation of any microcavities, but only those that reside between solid bridges. As taught in the specification, it is these microcavities and solid bridges that facilitate handling and further processing of the wafer [] prior to detachment of the thin layer by the application of mechanical forces.” (JA-0094-95) (emphasis added) Further, there is “ample guidance in the prior art for the formation of microcavities or bubbles in a substrate through the introduction of ions.” (JA-0095) The examiner disagreed, insofar as the specification teaches that other methods result in undesirable surface blistering. (JA-0151) In response, the applicants amended the claims from “introducing ions” to “introducing hydrogen ions” to form the microcavities, and further limited the claims to require that the “hydrogen ions are introduced into the first substrate at a temperature and at a total amount so as to not fracture the solid bridges during energizing of the first substrate.” (JA-0155)
The foregoing is insufficient to limit the claims to bridges that are able to withstand 400-700° C thermal treatments as MEMC suggests. The claims are cast broadly. MEMC does not cite, and the court has not located, a clear and unmistakable disclaimer of claim scope made during prosecution of the Aspar patents. See Cordis Corp., 561 F.3d at 1329. The claims require only that the bridges be “solid.”
Soitec does not specifically argue that the '564 patent does not disclose solid bridges. Rather,
even if Soitec’s claim construction of “bridges” is adopted, and even if the Bruel patent discloses a process in which “bridges” of material remain between the thin film and the rest of the substrate up to the point where the wafer is split, and even if that disclosure anticipates the “bridges” limitation of the asserted Aspar patent claims, that does not mean that Bruel anticipates the asserted claims. MEMC’s problem remains that the Bruel specification does not teach the claimed used of “mechanical force” [ ] to split the wafers.
(D.I. 247 at 9-10) (emphasis in original) The court turns now to that assertion.
(2) “Mechanical forces”
The parties propose the following competing instructions for the “mechanical forces” limitation of the '009 patent claims:
MEMO seeks the broader construction here, as it seeks to encompass within the claims the “internal mechanical forces” occurring during the heat treatment step (i.e., thermal cleaving). (D.I. 167 at 35)
“Separation” was addressed at length in the context of the SiGen litigation. As noted previously, claim 1 of the '564 patent described a process having three stages for the preparation of thin semiconductor films. In the third, thermal treatment stage, “a separation between the thin film and the majority of the substrate” was effected. In the SiGen litigation, the Federal Circuit found that “separation” is not limited to a complete separation or perfect cleavage between the layers. Specifically:
The specification of the '564 patent describes “a separation” created during the thermal treatment “by a crystalline rearrangement effect in the wafer and a pressure effect in the microbubbles.” The separation results from the thermally induced “crystalline rearrangement” and “coalescence of .the bubbles.” The specification does not require the “coalescence of the bubbles” to form a perfect cleavage between the top of the film and the bottom substrate. “Splitting or cleaving” the whole layer uniformly is a limitation not found in the '564 patent.
SiGen, 81 Fed.Appx. at 736-37.
On reexamination, the examiner addressed a protestor’s argument that “cleaving” was not sufficiently described for § 112 purposes because “[njowhere does the specification of the '564 patent describe any cleaving technique other than thermal cleaving.” (MA-0518) The protestor sought limitation of the claims to thermal cleaving techniques. The examiner found the argument unpersuasive in the absence of any teaching of “thermal cleaving” in the '564 patent specification and in view of the teaching of cleaving in four locations in the specification, for example, figure 4.
The examiner found “cleaving” to be enabled in view of evidence showing “that cleaving was considered to be a conventional technique to one of ordinary skill in the semiconductor manufacturing art at the time of the '564 patent, (see U.S. [Patent No.] 5,036,023-col. 3, lines: 45-52) which states, ‘the inventive method also comprises a variety of conventional steps, exemplarily including ... dicing or cleaving of a semiconductor wafer ... Such processing steps are conventional and require no detailed discussion.’ ” (MA-0521) (emphasis in original)
It is presumably because the examiner dismissed the argument that the claims of Bruel were limited to “thermal cleaving” that MEMO seeks a construction of the Aspar patent claims encompassing both thermal and mechanical cleaving. The As-par patents’ specification provides, however, that “the separation requires an extra step of applying mechanical forces” to achieve a separation during the thermal treatment. ('009 patent, col. 3:34-35) Although the court discerns no occasion to add Soitec’s proposed “external” forces limitation, MEMO cannot read out the separate separation step. Put another way, the forces internal to the wafer during the thermal treatment step cannot also constitute the “mechanical forces” of the subsequent separation step.
d. The '009 patent: anticipation by Bruel
(1) Standard
An anticipation inquiry involves two steps. First, the court must construe the claims of the patent in suit as a matter of law. See Key Phar. v. Hereon Labs. Corp., 161 F.3d 709, 714 (Fed.Cir.1998). Second, the finder of fact must compare the construed claims against the prior art. See id. A finding of anticipation will invalidate the patent. See Applied Med. Resources Corp. v. U.S. Surgical Corp., 147