ADE Corp. v. KLA-Tencor Corp. (252 F. Supp. 2d 40, 2003)

United States District Court for the District of Delaware 2003-03-13

Citations

Full opinion text

OPINION

JORDAN, District Judge.

I. INTRODUCTION

This matter is before the Court for construction of the claims in U.S. Patent No. 6,292,259 B1 (issued Sept. 18, 2001) (the “ ’259 patent”), pursuant to Markman v. Westview Instruments, Inc., 52 F.3d 967 (Fed.Cir.1995) (en banc), aff’d, 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996). Plaintiff ADE Corporation (“ADE”) and defendant KLA-Tencor Corporation (“KLA”) own United States patents used in the silicon wafer inspection industry to detect and classify silicon wafer surface defects as either crystalline originated pit defects or particle defects. On October 10, 2000, ADE filed its complaint in this action, alleging that KLA’s products infringed its U.S. Patent No. 6,118,525 (issued Sept. 12, 2000) (the “ ’525 patent”). (D.I. 1.) KLA counterclaimed, alleging that ADE’s products infringed several of its patents, specifically U.S. Patent Nos. 5,226,118 (issued July 6, 1993); 5,883,710 (issued Mar. 16, 1999); 6,081,325 (issued June 27, 2000); and 6,215,551 (issued Apr. 10, 2001). (D.I.7.) Thereafter, ADE amended its complaint, claiming that KLA is infringing the ’259 patent. (D.I. 232.) The Court’s magistrate judge previously provided an opinion recommending the proper construction of the ’525, ’118,-’710, ’325, and ’551 patents. See Ade Corp. v. KLA-Tencor Corp., 220 F.Supp.2d 303 (D.Del.2002). Those recommendations are the subject of still pending objections by both parties (see D.I. 531, 533) which are partially addressed in this opinion.

II. THE’259 PATENT

A. In General

The technology underlying the ’259 patent bears on the challenge of inspecting silicon wafers prior to their being manufactured into integrated circuits, also called “computer chips.” All of the patents at issue in the case relate to a strategy for addressing that challenge. As is more fully described herein, the ’259 patent teaches the use of a beam of specially polarized light that is directed at an angle to the surface of a silicon wafer or similar workpiece and manipulated to scan the surface for defects. The light deflected from the surface during the scan is then collected and analyzed to determine whether its deflection pattern is characteristic of one or the other of two types of silicon wafer defects, namely pit defects or particle defects. The distinction is important to chip manufacturers because particle defects can be cleaned off the wafer surface but pit defects, which, as the name implies, are actual flaws in the surface, cannot be. Thus, the accurate identification and classification of the two types of defects can lead to significant cost savings in the manufacturing process.

B. The ’259 Disclosure

The ’259 patent teaches a silicon wafer surface inspection system that uses a focused beam of P-polarized light to scan the surface of a silicon wafer or other workpiece. (D.I. 627, ’259 Patent Prosecution File History, ’259 patent at col. 1 11.39-56.) Claim 1 of the patent is representative of the invention:

1. A surface inspection system for distinguishing between particle defects and pit defects on a surface of a workpiece comprising:

an inspection station for receiving the workpiece;

a scanner positioned to scan a surface of the workpiece at the inspection station, the scanner including a light source arranged to project p-polarized light at an angle of incidence oblique to the workpiece surface;

a first collector positioned to collect light scattered from the surface of the workpiece at a central zone;

a second collector positioned to collect light scattered from the surface of the workpiece at an oblique zone offset an-gularly from the central zone;

one or more converters for converting the collected light components into respective signals representative of the light scattered into the central zone and oblique zone; and

a system controller configured to receive the signals, compare the signals, and classify defects as pits or particles based at least in part on the comparison.

(Id. at col. 12 11.18-38.) Figures 3 and 4, reproduced below, represent the preferred embodiment, as detailed in the ’259 written description and drawings. (Id. at col. 5 1. 31 to col. 71. 5.)

The preferred embodiment employs a multi-piece scanner (depicted as item “80” in Figure 4) arranged to scan the surface of a workpiece with a beam of P-polarized light generated from a light source (item “81” in Figures 3 and 4). The beam of P-polarized light is directed at the surface of the workpiece with a mirror (item “82”), a deflector (item “85”), and optical lenses (items “84” and “86”). (Id.) As the beam of P-polarized light scans the surface of

the workpiece, part of it refracts off the surface and is collected for analysis using a dark channel detector (item “120” in Figure 3) consisting of scattered-light collectors (items “121,” “123,” and “125”) in optical communication with and electrically connected to a forward channel detector (item “122”), a center channel detector (item “124”), and a back channel detector (item “126”). (Id. at col. 7 1. 24 to col. 8 1. 24.)

Figures 6 and 16, reproduced below, provide further information about the operation of the preferred embodiment.

As shown in Figure 6, the inventors specify that the placement of the three collectors (items “121,” “123,” and “125”) is determined with reference to the angle of incidence (designated as “0i” in Figure 6) of the light beam directed at the wafer surface and the angle of refraction (designated as “%0r”) of the light beam as it bounces off the wafer surface. The three collectors gather for analysis the light scattered from the wafer surface in forward, center, and backward regions. (Id.) The inventors specify a mathematical algorithm for processing the information about the scattered light (Figure 16), after it is collected in those regions. The operation of that algorithm is detailed in the ’259 written description.

In less technical terms, the invention works by bouncing a beam of light off the wafer surface and “reading” the scatter patterns of the light as it strikes a defect. When the beam strikes a particle defect, it tends to scatter light predominately outward, away from the center of the defect, so that, in the preferred embodiment, the forward and backward light collectors would register more scattered light than would the central light collector. When the beam strikes a pit defect the light is scattered more evenly.

C. The Prosecution Histories

The ’259 patent stems from a lengthy chain of continuing applications which requires an extended description, as it figures prominently in the bases for the Court’s decision. The ’259 patent derives from a continuation application of U.S. Application Serial No. 08/958,230, filed October 27, 1997 (now the ’525 patent), which, in turn, is a continuation-in-part of Application Serial No. 08/399,962, filed March 6, 1995 (now U.S. Patent 5,712,701) (issued Jan. 27, 1998) (the “ ’701 patent”). The ’701, ’525, and ’259 patent prosecution file histories, therefore, may aid the Court when construing the claims of the ’259 patent. See, e.g., Jonsson v. Stanley Works, 903 F.2d 812, 817-21 (Fed.Cir.1990).

1. The ’701 Prosecution History

ADE’s ’701 patent is entitled “Surface Inspection System and Method of Inspecting Surface of Workpiece.” Lee D. Clementi and Michael E. Fossey are the named inventors. Independent claim 1 of the ’701 patent is representative of the invention:

1. A surface inspection system for detecting particles or defects on a surface of a workpiece, the surface inspection system comprising:

means for translationally transporting a workpiece along a material path;

means associated with said transporting means for rotating a workpiece during translational travel along the material path;

a scanner positioned and arranged to scan a surface of a workpiece during rotational and translational travel along the material path, said scanner including a light source arranged to generate a light beam therefrom and means positioned to receive the light beam and arranged for scanning the light beam along a predetermined scan path across a surface of the workpiece as the workpiece rotationally and translationally travels along the material path; and

a collector arranged for collecting light reflected as scattered from the surface of the workpiece during rotational and translational travel along the material path, said collector comprising:

a light channel detector arranged for detecting light specularly reflected from the surface of a workpiece; and

a dark channel detector positioned adjacent said light channel detector for detecting light scattered from the surface of a workpiece, said dark channel detector including a plurality of collectors positioned closely adjacent each other and arranged for collecting components of the scattered light at different respective predetermined angles from the surface of the workpiece.

(D.I. 627, ’701 Patent Prosecution File History, ’701 Patent at col. 14 ll.6-37.)

The patent application leading to the ’701 patent was originally filed with 44 claims. (See id. at ’701 Patent Prosecution File History, Application Serial No. 08/399,962.) On March 4,1996, an examiner at the United States Patent and Trademark Office (“PTO”) allowed claims 8-21, 28-31, 33, 37, 38, 40-44; rejected claims 1-5, 22-27, 32, 34, 36, and 39; and objected to claims 6, 7, and 35. (Id. at ’701 Patent Prosecution File History, Office Action mailed Mar. 4, 1996 at 1-3.) Claims 1-5 were rejected pursuant to 35 U.S.C. § 103(a) “as being unpatentable over Jann et al (U.S. 5,189,481) in view of Yoshii et al (U.S. 5,461,474).” (Id. at 3, ¶ 3.) The examiner commented that these claims were rejected because:

It is known in the art in a wafer test using a spiral scan to measure not only scattered light but reflected light as well; see Jann et al., which detects Scattered light using [a] detector ... and reflected light using [another] detector .... It would have been obvious to use in the apparatus of Jann et al a small “sub-scan” as taught by Yoshii et al to improve the detection of small particles in the manner taught by Yoshii et al.

(Id.)

Claims 22-27, 32, 34, 36, and 39 were also rejected pursuant to Section 103(a) as “unpatentable over Yoshii et al (U.S. 5,461,474) in view of Steigmeier et al (U.S. 4,314,763).” (Id. at 1, ¶ 2.) As to these claims, the examiner commented:

Yoshii et al teaches that the detection of foreign matter on the surface of an object in a two-dimensional scanning system can be enhanced by “sub-scanning” the scanning beam by a small amount as it scans the wafer. Yoshii et al teaches that this “sub-scanning” can be performed by the use of an acousto-optic deflector; see figure 9 of the reference, for example.

While Yoshii et al shows this technique being used with a scanning system in a orthogonal scanning pattern which the scan in one direction is accomplished by scanning the light beam and the other direction by moving the object being scanned, it would have been obvious that this technique would be equally as useful with other known means of accomplishing a scan, including the known spiral scan system of the sort taught by Steig-meier et al.

(Id.)

The examiner then provided the applicants with some remarks. (Id. at 3-5, ¶¶ 4-9.) In particular, the examiner stated that “[t]he art does not appear to teach adjusting the speed of the scanning system to maintain a constant scan speed ... [and] [t]he art does not appear to the us [sic] of a dark channel detector comprising a plurality of collectors ... to detect light at different predetermined angles, in particular both forwardly and backwardly scattered light, nor, in combination, normally scattered light.” (Id. at 3-4, ¶¶ 4-5.)

On August 2, 1996, the applicants, responded to the examiner’s rejections. (Id. at ’701 Patent Prosecution File History, Applicants’ Response to Office Action mailed Mar. 4, 1996.) As to claims 22, 27, 32, and 39, the applicants stated that these claims:

[C]laim a machine or process that scan each portion of the workpiece surface. The acousto-optical deflector provides a narrow subscan that, coupled with a spiral scan path, covers the entire workpiece surface. This subscan allows the use of a small spot size to increase the sensitivity and spatial resolution of the scan, while maintaining rapid scan coverage of the entire surface of the workpiece. Thus, the invention provides high spatial resolution, complete coverage of the workpiece surface, and high throughput. Previous surface inspection systems could maximize high spatial resolution (but with a lower throughput or incomplete coverage) or maximize throughput or coverage (but at a lower sensitivity because of the use of a larger spot size). Before this invention, however, no surface inspection system was able to maximize all three criteria.

(Id. at 1-2.) The applicants further stated that the prior art does not “suggest a way to adjust for the change in orientation relative to the light beam[ ]” created when a subscan of a workpiece is performed along a spiral scan pattern. (Id. at 2-3.) The applicants then commented that the prior art, unlike their invention, “fails to teach or suggest a scanning system ... that maximizes all three critical criteria, high spatial resolution, complete coverage of the workpiece, and high throughput.” (Id. at 3.)

As to claims 1-5, the applicants responded:

Claims 1-5 were rejected as being obvious to use a spiral scan as taught by Jann with a small subscan as taught by Yoshii to improve the detection of small particles in the manner taught by Yoshii .... Yoshii does not teach how to incorporate a Yoshii-type subscan into a spiral scan pattern as taught by Jann. In addition, the multiple subscans taught in Yoshii result in reduced throughput. Jann also fails to teach how to incorporate a subscan into its spiral scanning surface inspection system.

In contrast, the present invention teaches a single scan over each area of the wafer. The subscan permits the use of a small spot size for high resolution of artificial defects, while maintaining complete scanning of the wafer surface and high throughput. The present invention does not use multiple scans of the same area of the wafer, nor does the present invention use any type of correlation analysis ....

(Id. at 3-4.) In response to the rejection of claims 22-27, 32, 34, 36, and 39, the applicants argued:

Steigmeier describes a typical spiral scanning system that provides complete coverage of the wafer surface. Stieg-meier, however, does not teach any method of improved spatial resolution or increased throughput, and fails to suggest a method for introducing a subscan to a system providing a spiral surface scan of a workpiece.

(Id. at 3.)

On October 23, 1996, an examiner issued a Final Office Action allowing claims 8-21, 28-31, 33, 37, 38, and 40-44; rejecting claims 1-5, 22-27, 32, 34, 36, and 39; and objecting to claims 6, 7, and 35. (Id. at ’701 Patent Prosecution File History, Final Office Action mailed Oct. 23, 1996 at 1-2.) The examiner further specified that claims 1-5, 22-27, 32, 34, 36, and 39 were again rejected under Section 103(a) as unpatentable given the prior art. (Id. at 2-3, ¶¶ 2-3.) With regard to claims 1-5, the examiner reiterated that those claims were “unpatentable over Jann et al (U.S. 5,189,481) in view of Yoshii et al (U.S. 5,461,474).” (Id. at 3, ¶ 3.) The examiner commented:

It would have been obvious to use in the apparatus of Jann et al a small “sub-scan” as taught by Yoshii et al to improve the detection of small particles in the manner taught by Yoshii et al.

(Id.) The examiner then provided the applicants with more remarks. (Id. at 3-6, ¶¶ 4-10.)

The examiner first noted that the applicants’ statement “that the system of Yoshii et al would not work with a spiral scan does not appear correct[ ] [because] ... any changes in orientation that may occur during the subscan would be negligible.” (Id. at 3, ¶ 4.) The examiner then commented that “[t]he rejected claims call for scanning systems with a main scan and a smaller subscan; this is taught by Yoshii et al.” (Id. at 4, ¶ 5.) The examiner restated that “the art does not appear to teach adjusting the speed of the scanning system to maintain a constant scan speed ... [and] the art does not appear to the us [sic] of a dark channel detector comprising a plurality of collectors ... to detect light at different predetermined angles, in particular both forwardly and backwardly scattered light, nor, in combination, normally scattered light.” (Id. at 3-5, ¶¶ 4, 6.)

On January 20, 1997, the applicants amended their application consistent with the examiner’s Final Office Action. (Id. at ’701 Patent Prosecution File History, Amendment After Final dated Jan. 20, 1997.) Claim 1 was amended to add, as elements of the claim, a light channel detector and a dark channel detector. (Id. at 1-2.) Claim 22 was amended to include a “means for varying the speed of rotating the workpiece ... during the scan ... so as to provide substantially constant scanning speed of the surface of the workpiece.” (Id. at 2.) Claim 32 was amended to add the step of “separately collecting light specularly reflected from and fight scattered from the surface of the workpiece _” (Id. at 3.)

Thereafter, on February 4, 1997, pursuant to the applicants’ January 20, 1997 amendments, an examiner allowed claims 1-5, 7-32, and 34-44. (Id. at ’701 Patent Prosecution File History, Notice of Allowa-bility mailed Feb. 4, 1997.) The ’701 patent issued on January 27,1998.

2. The ’525 Prosecution History

The ’525 patent is entitled “Wafer Inspection System for Distinguishing Pits

and Particles.” Michael E. Fossey, John C. Stover, and Lee D. Clementi are the named inventors. Independent claim 1 of the patent is representative of the invention:

1. A surface inspection method for distinguishing between particle defects and pit defects on a surface of a workpiece, said method comprising:

receiving the workpiece at an inspection station;

scanning the surface of the workpiece at the inspection station with a beam of P-polarized fight at an angle of incidence oblique to the workpiece surface;

collecting fight scattered from the surface of the workpiece at the inspection station at a first central zone, and at least at a second oblique zone offset angularly from said first zone;

converting the collected fight components from said zones into respective signals representative of fight scattered into said zones;

comparing said signals; and

determining whether a defect is one of a pit and a particle based at least on said comparing.

(D.I. 627, ’525 Patent Prosecution File History, ’525 Patent at col. 1211.19-36.)

The patent application leading to the ’525 patent was originally filed with 29 claims. (See id. at ’525 Patent Prosecution File History, Application Serial No. 08/958,230.) In an Office Action mailed June 5, 1998, an examiner at the PTO rejected each of the applicants’ claims pursuant to 35 U.S.C. § 103(a) “as being un-patentable over Quackenbos et al (4794264) in view of Wells et al (5355212).” (Id. at ’525 Patent Prosecution File History, Office Action mailed June 5, 1998 at 1-3.) The examiner explained that Quacken-bos teaches using a light beam from any known source to scan the surface where “[t]he perpendicular scattered light, caused by pits ... [are] detected by [the item designated as “28” in the Quackenbos patent] and the other scattering angles, both back scattered light and forward scattered light, ... is detected using [a] sensor [designated as item “48” in the Quacken-bos patent].” (Id. at 3.) The examiner noted that Quackenbos compares the intensity of the light in these sensed regions to determine whether there is a pit or a particle on the surface and it maps the location of the pits. (Id.) However, Quack-enbos did not teach “the use of a laser scanning at an angle of the surface, and the use of the system to distinguish and map both the flaws, being either a pit or particle.” (Id.)

The examiner next turned to the Wells patent, explaining that Wells, like Quack-enbos, teaches the use of a light beam to scan a wafer surface. (Id.) The perpendicularly and other angularly scattered light is then collected and analyzed to “map the surface of the wafer ... for defects (pits, scratches, etc..), particles, and patterns of the wafer. The system can be used to determine ... the sensing of a defect/particle ... either a pit or particle.” (Id. at 3-4.) The examiner then commented that:

[I]t would have been obvious to an artisan at the time ... to employ a notoriously old and well known use of a scanning laser system which irradiated the surface at an angle, and a system which no [sic] only detects the surface for both pits and particles, but maps both ... where the combination of the teachings would provide an overall system which would combine two necessary determinations and methods into one by detecting the different scattering angles off a surface, comparing the scattering intensities to each other or thresholds, and mapping the surface of a wafer for both the unique features found, pits and particles ....

(Id. at 4.)

On August 26, 1998, the PTO received the applicants’ response to the examiner’s June 5, 1998 Office Action. (Id. at ’525 Patent Prosecution File History, Applicants’ Response to Office Action mailed June 5, 1998.) In their response, the applicants first gave a description of their invention, stating:

[T]he apparatus and methods of the invention employ a plurality of collectors arranged at different angular positions relative to the workpiece for collecting back-scattered, forward-scattered, and perpendicularly scattered light.... By comparing the light intensity in the center region to the light intensity in the backward and/or forward regions, a defect can be classified as either a pit or a particle.

As further explained below, both Quackenbos and Wells wholly fail to teach or even remotely suggest the importance of ... collecting scattered light in the backward, center, and forward-scattered regions, and comparing the intensities in these three regions to discriminate pits from particles.

(Id. at 2-3.)

In a further effort to distinguish their invention, the applicants repeated that Quackenbos “does not separately collect back-scattered and forward-scattered light, nor does he compare the intensities of scattered light in different regions in order to discriminate a pit from a particle.” (Id. at 5.) Moreover, asserted the applicants,

[In Quackenbos] there are not truly any “back-scatter” or “forward-scatter” directions. Rather, light is scattered by a defect in a conical volume .... Thus, it is clear that Quackenbos, ... does not separately collect back-scattered and forward-scattered light. Moreover, he does not compare two detected intensities, but merely detects whether signals are present on the near-specular and far-specular sensors.

Additionally, Quackenbos does not disclose how the near-specular and far-specular sensors should be arranged if, as suggested at column 3, lines 56-58, the incident light beam can be directed non-perpendicular to the surface. The disclosure wholly fails to teach or suggest that non-perpendicular incidence is preferable, and does hot even recognize that non-perpendicular incidence can give different results in terms of the angular distribution of scattered light.

In short, Quackenbos completely fails to teach or suggest the important aspects of Applicants’ invention, namely, that ... scattered light should be collected in backward, center, and forward regions, and that the intensities in these regions should be compared in order to discriminate pits from flaws.

(Id. at 5-6.) As to Wells, the applicants remarked, “Wells collects scattered light at only two locations neither of which is positioned in the back-scatter region.” (Id. at 6.)

With this backdrop, the applicants went on to argue that their original claims 1 and 12 were patentable because, “[n]either of the references teaches or suggests comparing scattered light intensities in different angular locations.” (Id. At 7.) Moreover asserted the applicants:

[NJeither reference teaches or suggests the additional recitation of claim 12 which recites a center channel collector for collecting perpendicularly scattered light and a back channel collector for collecting back-scattered light, and a comparer for comparing the signals from the center and back channel collectors. As noted, neither Quackenbos nor Wells separately collects back-scattered light.

(Id. at 7-8.)

In a later Office Action, mailed November 10, 1998, an examiner at the PTO stated that the applicants’ foregoing arguments with respect to claims 1-29 were considered but were moot since the claims were unpatentable under Section 103(a) “over Fo'ssey et al. (WO-96/27786) in view of Well’s (5,355,212).” (Id. at ’525 Patent Prosecution File History, Office Action mailed Nov. 11, 1998 at 1-4.) The applicants responded to the examiner’s November 10, 1998 Office Action by adding new claims 30-51, amending the specification to convert the application into a continuation-in-part application, stating that the examiner’s Fossey et al. (WO-96/27786) reference could not constitute prior art because it is one of the applicants’ own publications, and stating that “[t]he Wells patent fails to teach the claimed invention.” (D.I. 627, ’525 Patent Prosecution File History, Applicants’ Response to Office Action mailed Nov. 11, 1998 at 6-8.) That is so, asserted the applicants, because “no effort is made [in Wells] to compare scattered light intensities in different angular locations so as to discriminate one type of defect from another.” (Id. at 8.)

By Office Action mailed on October 28, 1999, an examiner rejected claims 1-51 “under 35 U.S.C. 103(a) as being unpatentable over Orazio et al. (5,032,734) in view of Hayano et al. (4,966,457).” (Id. at ’525 Patent Prosecution File History, Office Action mailed Oct. 28, 1999 at 3.) The examiner explained that “Orazio disclosed an apparatus for detecting the defects on worksurfaces [sic] by observing the scattered light beams[ ] [and explains] ... the physical behavior of either P-polarized light beam or the S-polarized light beam....” (Id.) The examiner then stated that although Orazio fails to teach two detectors at different angles, “Hayano implements at least two set [sic] of detecting devices in order to maximize the detection of scattered lights.” (Id. at 3.)

On January 26, 2000, the applicants responded to the examiner’s October 28, 1999 Office Action with argument, can-celled claims 1-51, and added new claims 52-72. (Id. at ’525 Patent Prosecution File History, Applicants’ Response to Office Action mailed Oct. 28, 1999.) New claim 52, which became independent claim 1 of the ’525 patent, contains the step of “collecting light scattered from the surface of the workpiece at the inspection station at a first central zone, and at least a second oblique zone offset angularly from said first zone.” (Id. at 1 (emphasis added).) The sole explanation given by the applicants for the new language “central zone” and an “oblique zone” is that an examiner “viewed it favorably” at an interview dated October 27,1999. (Id. at 4.)

Thereafter, on March 28, 2000, an examiner allowed claims 52-72. (Id. at ’525 Patent Prosecution File History, Notice of Allowability mailed Mar. 28, 2000.) The ’525 patent issued on September 12, 2000.

3. The ’259 Prosecution History

The ’259 patent is entitled “Wafer Inspection System For Distinguishing Pits and Particles.” The named inventors are Michael E. Fossey, John C. Stover, and Lee D. Clementi. Claim 1, which has already been quoted, supra at 4, is representative of the invention. By Office Action dated March 23, 2001, an examiner rejected the claims of the patent application (patent application Serial No. 09/624,-502) that ultimately led to the ’259 patent, stating that, under Section 103(a), they were “unpatentable over Nikoonahad et al (U.S. 5,883,710).” (D.I. 627, ’259 Patent Prosecution File History, Office Action dated Mar. 23, 2001 at 3.) The examiner explained that Nikoonahad teaches a surface inspection system that scans the surface of a workpiece with a light beam at an oblique angle of incidence to the workpiece surface and collects the scattered light in four different collectors which “provide output signals to a processor to detect and analyze the characteristics of anomalies.” (Id.) The examiner did note that “Nikoona-had does not disclose expressly a converter, a comparator, a classifier, and a system controller with a video-display.” (Id.) But, the examiner said, these elements “do not differentiate the claimed apparatus from the apparatus of Nikoonahad....” (Id.)

On May 16, 2001, the PTO received the applicants’ response to the examiner’s March 23, 2001 Office Action. (Id. at ’259 Patent Prosecution File History, Applicants’ Response to Office Action dated Mar. 23, 2001.) In their response, the applicants added • new claims 72-76, amended claims 30, 34-39, 41, 50, 52-54, 55, 59, 61, and 62, and attempted to distinguish their invention from the Nikoonahad patent. (Id. at 1-17.) Specifically, the applicants amended many of the claims to include the phrase “the collected light components are converted into respective intensity signals representative of the intensity of the light scattered into the central zone and oblique zone.” (See, e.g., id. at 13, amended claim 37 (emphasis added).) Again, as in the ’525 patent application process, addition of the “central zone” and “oblique zone” language was made at the end of patent prosecution and the phrases are not used in the written description or drawings.

On June 5, 2001, an examiner allowed claims 30-76. (Id. at ’259 Patent Prosecution File History, Notice of Allowability mailed June. 5, 2001.) The ’259 patent issued on September 18, 2001.

III. CLAIM CONSTRUCTION

A determination of patent infringement «involves two steps. First, the patent claims are construed, and, second, the claims are compared to the allegedly infringing device. Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1455 (Fed.Cir.1998) (en banc). Claim construction is a matter of law for the Court. Markman, 52 F.3d at 979. “To properly construe the claims, a court must examine the claims, the rest of the specification, and, if in evidence, the prosecution history.” Amgen Inc. v. Hoechst Marion Roussel, Inc., 314 F.3d 1313, 1324 (Fed.Cir.2003). The process begins, however, with the language used in each claim itself. See, e.g., Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). It is that language that defines and measures the scope of a patented invention. See, e.g., SRI Int’l v. Matsushita Elec. Corp. of Am., 775 F.2d 1107, 1121 (Fed.Cir.1985) (en banc).

If possible, claim language is given the ordinary and accustomed meaning understood by practitioners in the art. Hockerson-Halberstadt, Inc. v. Avia Group Int’l, Inc., 222 F.3d 951, 955 (Fed.Cir.2000). There is a “heavy presumption” that, if such a meaning exists, it is the meaning intended. Bell Atl. Network Servs., Inc. v. Covad Communications Group, Inc., 262 F.3d 1258, 1268 (Fed.Cir.2001). That presumption does not control, however, when the inventor deviates from the ordinary and accustomed meaning by acting as a lexicographer or when the ordinary and accustomed meaning would deprive the claim, as a whole, of an ascertainable meaning. Id. The intrinsic record before the court, therefore, “must be examined in every case to determine whether the presumption of ordinary and customary meaning is rebutted.” Texas Digital Systems, Inc. v. Telegenix, Inc., 308 F.3d 1193, 1204 (Fed.Cir.2002). If there is no clear, ordinary and customary meaning in the claim language, then consideration of the rest of the intrinsic evidence is directed to resolving, if possible, the lack of clarity. Interactive Gift Express, Inc. v. Compuserve Inc., 256 F.3d 1323, 1331 (Fed.Cir.2001).

If the meaning of a claim term remains unclear after considering the intrinsic evidence, a court may enlist the aid of extrinsic evidence “to help resolve the lack of clarity.” Interactive Gift, 256 F.3d at 1332; see also Mannington Mills, Inc. v. Armstrong World Indus., Inc., 218 F.Supp.2d 594, 598 (D.Del.2002) (“When the extrinsic record can provide a meaning eluding the court’s grasp, a court should adopt such a construction if that construction is cognizant with the overall intrinsic record before it.”) (citing Vitronics, 90 F.3d at 1583). Use of extrinsic evidence, however, is restricted. “Relying on extrinsic evidence to construe a claim is ‘proper only when the claim language remains genuinely ambiguous after consideration of the intrinsic evidence.’ ” Interactive Gift, 256 F.3d at 1332. Extrinsic evidence may not “contradict the import of other parts of the specification [or intrinsic record]. Indeed, where the patent documents are unambiguous, expert testimony regarding the meaning of a claim is entitled to no weight.” Id. Neither are inventors entitled to an after-the-fact claim construction inapposite to the “clear import of the patent disclosure itself.” North Am. Vaccine, Inc. v. Am. Cyanamid Co., 7 F.3d 1571, 1577 (Fed.Cir.1993), cert. denied, 511 U.S. 1069, 114 S.Ct. 1645, 128 L.Ed.2d 365 (1994).

Further, amendments or cancellations of claims as well as arguments or other statements made during prosecution of earlier filed applications in a chain of continuing applications may limit construction of claims in later filed continuing applications if there exists a nexus between those earlier statements and the later filed claims. See Augustine Medical, Inc. v. Gaymar Industries, Inc., 181 F.3d 1291, 1300 (Fed.Cir.1999) (cancelling or amending all original claims in an earlier application in favor of new claims to traverse an examiner’s rejection evidenced a narrowing of claim coverage); Mark I Mktg. Corp. v. R.R. Donnelley & Sons Co., 66 F.3d 285, 291-92 (Fed.Cir.1995), cert. denied, 516 U.S. 1115, 116 S.Ct. 917, 133 L.Ed.2d 847 (1996) (amending original claims in a series of continuation-in-part applications to gain allowance by making them narrower evidenced a surrender of claim scope); Jonsson, 903 F.2d at 818 (holding that the prosecution history and construction of the term in a parent application was relevant to construing the same term in a patent issued on a continuation-in-part application based on the parent application).

The terms at issue in the ’259 patent are as follows: “oblique zone,” “scan,” “scanner,” “scan a surface of the workpiece,” “collector,” “scattered from the surface of the workpiece,” “one or more converters,” “substantially only backscattered light,” “predetermined value,” “predetermined measure,” “threshold value,” “determines the size of the pits and particles,” “groups the pits and particles based at least in part on the determination of size,” “map,” “system controller,” “comparator,” “classifier,” and “sorts the workpieces.” Following is the Court’s construction of each of those terms.

A. “oblique zone”

A suggested construction of the phrase “oblique zone” was given by the magistrate judge in addressing the related phrase, “a second oblique zone offset angularly from said first zone,” which is found in the ’525 patent. Ade Corp., 220 F.Supp.2d at 315-19. Pursuant to Federal Rule of Civil Procedure 72, ADE has objected to the recommendation of the magistrate judge on that point. (D.I. 533 at 15-22.) KLA, of course, urges the Court to adopt the construction suggested by the magistrate judge. (D.I. 615 at 1-12.) The Court takes this opportunity to deal with the term “oblique zone” as used in the ’259 patent to simultaneously address ADE’s objection to the magistrate judge’s recommendation regarding the related phrase in the ’525 patent. The following analysis is thus based not only on the parties’ submissions with respect to the ’259 patent but also on a de novo review of the evidence and arguments presented to the magistrate judge with respect to the phrase “second oblique zone offset angularly from said first zone” as found in the ’525 patent claims.

The magistrate judge observed that the phrase “second oblique zone offset angu-larly from said first zone” first appeared in the prosecution history of the ’525 patent “after being added almost two years into prosecution.” Id. at 317. Although ADE argued that the inventors did not intend for the phrase to have a specialized meaning and that “those skilled in the art would readily comprehend what is meant[,]” id., ADE was unable to offer any pertinent art reference that would explain the meaning of the phrase. Id. at 317. Instead ADE urged the Court to apply a dictionary definition of “oblique” as modifying a dictionary definition of the word “zone.” Id.

Turning to the specification and prosecution history of the ’525 patent for assistance, the magistrate judge stated that the separate collection of forward, central, and backward scattered light was consistent with the “internal logic” of the ’525 patent disclosure and it was also consistent with the applicants’ arguments during patent prosecution. Id. at 318-19. In light of the record, she construed the phrase “second oblique zone offset angularly from said first zone” to mean “a second collection zone differing in polar angle from the central collection zone that does not collect the same light being collected by the ‘central zone’ but, instead, collects either forward or backward scattered light but does not collect both simultaneously.” Id. at 319. The magistrate judge reached that conclusion by reasoning that, in prosecuting their application, “the inventors predicated patentability on separate collection of forward and/or backward scattered light ... in addition to collection of light scattered generally in the normal direction.” Id.

1. ADE’s Position

ADE devoted most of its Opening Claim Construction Brief (D.I. 595) to a discussion of the relevance and importance of the “oblique zone” claim limitation. It argues that Federal Circuit precedent requires the Court to first assess the ordinary meaning of individual claim terms such as “oblique” and “zone” before considering the remainder of the intrinsic record to arrive at a construction for a disputed claim phrase. (Id. at 14-16.) According to ADE, the magistrate judge failed to follow that course and was instead persuaded by KLA to read the preferred embodiment of the invention into the construction of “oblique zone,” which “resulted in the incorporation of the extraneous limitation that the oblique zone collects ‘either forward or backward scattered light but does not collect both simultaneously.’ ” (Id. at 16-17.) The correct course, says ADE, is for the Court to consider the dictionary definition of the word “oblique” because it has a plain and ordinary meaning which, when combined with the common word “zone,” gives the phrase “oblique zone” a plain and ordinary meaning as well. (Id. at 18-21.) The construction that ADE proposes be adopted would define “oblique zone” as “ ‘a light collecting zone positioned to collect light generally scattered obliquely (i.e., neither parallel nor perpendicular to the workpiece surface), and that is offset angularly from the central zone in the polar direction’ ”. (Id. at 3.)

ADE also asserts that the doctrine of claim differentiation supports its proposed construction for “oblique zone,” since dependent claims 3, 4, 5, and 6 of the ’259 patent “specify forward and backward limitations, reinforcing the breadth of claim 1.” (Id. at 22.) In other words, ADE contends that since there are dependent claims that do have explicit limitations on the separate gathering of forward and backward scattered light, it is error to read claim 1, from which those later claims depend, to include such a limitation. (See id.)

Finally, in an attempt to rebut efforts by KLA to focus the Court’s attention on the prosecution history of the patent, ADE argues that the intrinsic record is not clearly inconsistent with its proposed construction and does not evidence a clear and unambiguous disavowal of claim scope. (Id. at 22-27.)

2. KLA’s Position

As earlier noted, KLA asserts that the magistrate judge properly construed the phrase “oblique zone” and, therefore, the construction given the phrase in connection with the ’525 patent should apply to the ’259 patent as well. (D.I. 615 at 3.) In support of the approach taken by the magistrate judge, KLA points out that the magistrate judge first concluded that the phrase “oblique zone” has no ordinary or pertinent art meaning before she examined the remainder of the intrinsic record for guidance, all of which was and is consistent with Federal Circuit precedent. (Id. at 3-6.) Finally, KLA argues that an independent review of the issue should lead to the same result because the phrase “oblique zone” has no plain and ordinary meaning and, even if it did, the inventors restricted the construction of the phrase during patent prosecution, thus showing a clear and unequivocal disavowal of the construction proposed by ADE. (Id. at 7-12.)

3. Analysis

The Court rejects ADE’s effort to focus attention solely on dictionary definitions. It is true that, in Texas Digital, the Federal Circuit retreated from the notion that dictionaries, encyclopedias, and treatises are to be viewed as extrinsic evidence. Texas Digital, 308 F.3d at 1203 (“[Categorizing them [dictionaries, encyclopedias, and treatises] as ‘extrinsic evidence’ or even a ‘special form of extrinsic evidence’ is misplaced and does not inform the analysis.”). But, regardless of the label applied to those tools of construction, the Federal Circuit had endorsed their use before Texas Digital, see, e.g., Toro Co. v. White Consol. Indus. Inc., 199 F.3d 1295 (Fed.Cir.1999), and Texas Digital did not make them the “be all and end all” of claim construction or otherwise work a dramatic change in the process of construing claims. Indeed, the Court in Texas Digital, acknowledged that “[i]t has been long recognized in our precedent and in the precedent of our predecessor court, the Court of Customs and Patent Appeals, that dictionaries, encyclopedias and treatises are particularly useful resources to assist the court in determining the ordinary and customary meanings of claim terms.” Id. at 1202 (citations omitted). Afterwards, the Court stated that “the intrinsic record may show that the specification uses the words in a manner clearly inconsistent with the ordinary meaning reflected, for example, in a dictionary definition. In such a case, the inconsistent dictionary definition must be rejected.” Id. at 1204 (citations omitted). Thus, while dictionaries, encyclopedias, and treatises may be a starting point in the analysis, they are not necessarily the ending point. See id. at 1205 (“By examining relevant dictionaries, encyclopedias and treatises ... and by further utilizing the intrinsic record ... unintended limitations from the written description into the claims will be more easily avoided.”).

ADE would have this Court first recite a dictionary definition for each word in a contested patent claim phrase, add those definitions together, and adopt the resulting amalgamation as the Court’s construction before proceeding to any consideration of the remainder of the intrinsic record. The cases cited by ADE, however, do not require the cataloguing of dictionary definitions before construing disputed claim phrases, nor do they require the adoption of a definition equal to the sum of the individual definitions of the words in a contested phrase.

For example, in Inverness Medical Switzerland v. Princeton Biomeditech Corp., 309 F.3d 1365, (Fed.Cir.2002) (“Inverness I ”), a case cited by ADE in support of its argument, the parties disputed a claim phrase containing the word, “mobility.” 309 F.3d at 1369. The meaning of that word, reasoned the Court, was not disputed by the parties but was central to the controversy. Id. The Court, therefore, looked in a dictionary and chose, of the multiple dictionary definitions of “mobility,” the one most appropriate in view of the intrinsic evidence before the Court. Id. at 1369-70. The Court then used that definition in its construction of the remainder of the phrase in which the word appeared. Id.

In Inverness Medical Switzerland v. Warner Lambert Co., 309 F.3d 1373 (Fed.Cir.2002) (“Inverness II”), which ADE also cites, the Court “look[ed] ... to the dictionary definitions of the claim terms ‘on’ and ‘onto’ as of the date the patents issued.” 309 F.3d at 1378. Reasoning that the definition of the word “onto” referred to the word “on,” the Court concluded “that both prepositions are properly addressed through the interpretation of ‘on.’” Id. The Court then commented that the word “on” had an ordinary meaning encompassing two applicable dictionary definitions, therefore, the Court had to look to the remainder of the intrinsic record to “determine whether the specification or prosecution history clearly demonstrates that only one of the multiple meanings was intended.” Id. at 1378-79 (citing Renishaw PLC v. Marposs Societa’ per Azioni, 158 F.3d 1243, 1250 (Fed.Cir.1998)). The Court then reversed the lower court for adopting only one of the two applicable meanings because both possible constructions were viable, given the intrinsic record before the Court. Id. at 1379-82.

Similarly, in Schumer v. Lab. Computer Sys., Inc., 308 F.3d 1304 (Fed.Cir.2002), the Court held that the lower court’s “construction contradicts the plain meaning of the word ‘or’ in the claims.” 308 F.3d at 1311. The Court then looked to a dictionary to define this ordinary word and compared that definition to the intrinsic record and held that the intrinsic record did not compel a construction different from the ordinary meaning of the word. Id. at 1313-14.

Therefore, in contrast to what ADE seems to urge, the case law demonstrates that claim construction does not conclude with the shutting of a dictionary. If a court opts to use a dictionary when construing claims, it must still proceed to a consideration of remaining claim language and the remainder of the intrinsic record to determine whether the disputed claim language is used consistently with any ordinary meaning the claim language may have. A narrow approach to patent claim construction that focuses on summing dictionary definitions may well lead a court to adopt an inappropriate construction, one that is inconsistent with the pertinent art and the intrinsic record of the patent in suit. That danger is exacerbated when a phrase, rather than a single word, is at issue. The meaning of a phrase is often greater than the sum of the individual words. Ordinary experience with idiomatic phrases, particularly when translating them from one language to another, demonstrates the difficulties and misunderstandings that a literal, word-for-word translation can produce. A dictionary, encyclopedia, or treatise may also contain several definitions for the same word. In short, context is critical, and the import of the intrinsic record cannot be ignored. See Springs Window Fashions, LP v. Novo Indus., L.P.; 323 F.3d 989, 994-97 (Fed.Cir.2003) (noting that a patentee is held to what was said during patent prosecution when distinguishing prior art even though there is no explanation in the prosecution history for particular claim language because competitors must be able to look to the intrinsic record and rely upon it).

As previously noted, supra at 55, the magistrate judge reviewed the phrase “oblique zone” as part of the larger phrase “second oblique zone offset angularly from said first zone.” ADE asserts that the magistrate judge read a limitation into the construction of “oblique zone” from the preferred embodiment. (D.I. 595 at 16-17.) In fact, however, the magistrate judge merely acknowledged the difficulties in construing the phrase “oblique zone,” stating that the Court was “well aware ... that a preferred embodiment does not, necessarily, define the claimed invention as detailed by the language of the claims.” Ade Corp., 220 F.Supp.2d at 318. The magistrate’s Report and Recommendation went on to reason, in effect, that the phrase “oblique zone” was not clear on its face and that the inventors had failed to provide clues to its correct interpretation except through the intrinsic record and whatever further understanding could be gleamed from the description of the preferred embodiment. Id. at 318-19 (citations omitted). That conclusion about the phrase in the ’525 patent is sound and is equally true with regard to the term “oblique zone” as used in the ’259 patent. Cf. Schumer, 308 F.3d at 1312 (“It is' well established that statements made during prosecution are used to interpret the scope and meaning of ambiguous claim terminology.”) (citing Vitronics, 90 F.3d at 1582); E.I. du Pont de Nemours & Co. v. Phillips Petroleum Co., 849 F.2d 1430, 1438 (Fed.Cir.1988), cert. denied, 488 U.S. 986, 109 S.Ct. 542, 102 L.Ed.2d 572 (1988) (“[Arguments made during prosecution history are relevant in determining the meaning of the terms at issue. Those arguments ... must be examined to ascertain the true meaning of what the inventor intended to convey in the claims.”) (citations omitted); ZMI Corp. v. Cardiac Resuscitator Corp., 844 F.2d 1576, 1580 (Fed.Cir.1988), aff’d, 899 F.2d 1228 (1990) (rejecting patentees’ proposed construction of disputed claim term as inconsistent with prosecution history).

The phrase “oblique zone” was first added to the claims of the ’525 patent by amendment after an interview with a PTO examiner. (D.I. 627, ’525 Patent Prosecution File History, Applicants’ Response to Office Action mailed Oct. 28, 1999 at 4.) Under 37 C.F.R. § 1.133(b), it is the patntee’s responsibility to complete a written statement as to the substance of that interview. See also 37 C.F.R. § 1.2; Manual of Patent Examining Procedure § 713.04 pp. 700-166 to 700-168 (8th ed., Aug. 2001). Failure to adequately explain why an examiner approved of that language does not erase the preceding prosecution history, which includes prior art citations that the examiner viewed as rendering the invention obvious. See Tate Access Floors, Inc. v. Interface Architectural Res., Inc., 279 F.3d 1357, 1372 n. 4 (Fed.Cir.2002) (prior art cited by an examiner in the prosecution history is part of the intrinsic record of the patent). That prosecution history clearly weighs against the interpretation sought by ADE.

In an Office Action mailed June 5, 1998, an examiner at the PTO rejected the applicants’ original claims in the application leading to the ’525 patent because, as written, those claims were obvious under Section 103(a). (D.I. 627 at ’525 Patent Prosecution File History, Office Action mailed June 5, 1998 at 1-3.) Specifically, the examiner explained that a particular prior art reference known as “Quackenbos” made the claimed invention obvious:

Quackenbos teach [sic] of using a light beam ... to send light to surface ... of a disk ... which is moved and rotated ... to scan the entire surface in two directions. The perpendicular scattered light, caused by pits ... is detected ... and the other scattering angles, both back scattered light and forward scattered light ... is detected using [a] sensor .... The two detected intensities are compared in [a] comparator ... and then the system determines if the sensed region is a particle or pit where only the pits on the surface are mapped

(Id. at 3.) The examiner then explained that another prior art reference called “Wells” could* like the applicants’ invention and unlike the Quackenbos reference, “be used to determine ... the sensing of a defect/particle ... either a pit or particle[,]” thus, rendering the applicants’ invention obvious in light of the combination of those two references. (Id. at 3^4.)

There is little question from the quoted remarks that the examiner understood the pertinent art as disclosing a system that employs two detectors in which normally (or perpendicularly) scattered light is collected in one sensor and, in the other sensor, both forward and backward scattered light are collected for detecting defects on the surface of a silicon wafer or other workpiece. In Quackenbos, as de-pieted below in Figure 3 from that patent, the two sensors are conically shaped and depicted as item 28, which is capable of collecting perpendicularly scattered light, and as item 48, which is capable of collecting forward scattered light, back scattered light, and other light scattered in a 360 degree azimuthal range.

(D.I. 626 at U.S. Patent No. 4,794,264 (issued Dec. 27,1988), Figure 3.)

On August 26, 1998, the PTO received the applicants’ response to the examiner’s June 5, 1998 Office Action. (D.I. 627 at ’525 Patent Prosecution File History, Applicants’ Response to Office Action mailed June 5, 1998.) In that response, the applicants twice distinguished their invention from the Quackenbos reference by stating that “Quackenbos ... does not separately collect back-scattered and forward-scattered light....” (Id. at 5 (emphasis in original).) The applicants also characterized their invention as employing “a plurality of collectors arranged at different angular positions ... for collecting back-scattered, forward-scattered, and perpendicularly scattered light.” (Id. at 2.) In addition, the applicants asserted that in Quackenbos “there are not truly any ‘back-scatter’ or ‘forward-scatter’ directions. Rather, light is scattered by a defect in a conical volume.” (Id. at 5.) After making the foregoing statements with regard to their invention and the prior art, the applicants proceeded to a discussion of original claims 1 and 12. (Id. at 7.) As to those two claims, the applicants argued that neither Quackenbos nor Wells teaches or even suggests the additional recitation in claim 12 of separately collecting perpendicularly and back-scattered light. (Id. at 7-8.) Moreover, asserted the applicants, “[n]either of the references teaches or suggests comparing scattered light intensities in different angular locations.” (Id.) The applicants thus predicated the patentability of their invention on the separate collection of forward, backward, and perpendicularly scattered light.

In addition to the prosecution history that weighs heavily against ADE’s proposed construction, there is a significant question as to whether the invention would be enabled if ADE’s construction of “oblique zone” were adopted. Figure 16 and column 12 lines 19-36 of the ’259 patent written description disclose a mathematical algorithm for comparing the center channel signal to either or both of the forward channel signal or the back channel signal. This signal comparison algorithm is suited for comparing signals generated from forward, backward, and center “segmented” collection/detection apparatuses. The algorithm is not designed to process light signals produced from a center collection/detection apparatus and a single axi-symmetric collection/detection apparatus that collects both forward and backward scattered light in a 360 degree azimuthal range. Granted, the mathematical algorithm taught by the inventors is qualified by the following language in the specification:

It should be apparent to those of skill in the art from this illustration that the present invention is not limited to the particular algorithm described herein, and that other approaches and other specific algorithms may be used to process the data obtained from the various detectors and to distinguish between pits and particles in accordance with the present invention.

(D.I. 627, ’269 Patent Prosecution File History, ’259 Patent at col. 12 11.43-49 (emphasis added).) The Court is bound by what is disclosed. Those of ordinary skill in the art may be able to conceive of different algorithms to use in the ’259 invention, however, those algorithms must work in accordance with the disclosed invention, which processes distinct signals gathered from separate collectors. (Id.)

The disclosed algorithm processes signals from three different sources, a forward channel collector/detector, a back channel collector/detector, and a center channel collector/detector. An algorithm that can process separate signals for comparison is, it would seem, a much different endeavor then a mathematical algorithm that can be used to analyze a single signal representing light collected in a forward and backward scatter region generated by a single collector/detector and then compare the scattered light pattern of the forward and backward scattered light to the light collected in a central region to determine whether the collected light in those regions is characteristic of a pit or particle defect. Such an algorithm, one capable of processing axisymmetrie collected light, would be required to render the invention operable if ADE’s construction of “oblique zone” was adopted by the Court, since ADE’s construction would permit collection of forward and backward scattered light in one collector/detector positioned to collect light 360 degrees in the azimuthal range. There is, however, no disclosure in the ’525 or ’259 written descriptions or drawings supporting such an algorithm.

If the argument were made that the algorithm need not differentiate between forward and backward scattered light collected in a single apparatus because that is accomplished by the apparatus which collects the light from the two regions, then the ’259 and ’525 inventions do not teach a single collector/detector for capturing forward and backward scattered light and do not enable a single collector/detector that can perform such a function. Yet ADE’s proposed construction of “oblique zone” would encompass just such a single conical or axisymmetrie collector/detector, capable of capturing forward and backward scattered light and comparing the forward and backward collected light to light collected in a center channel collector/detector. Again, there is no teaching in the ’525 or ’259 written descriptions or drawings for such a device. ADE’s proposed construction of “oblique zone” is simply not supported by the ’525 or ’259 intrinsic record before the Court. Indeed, as noted by ADE’s efforts to distinguish Quackenbos and Wells, the record is contrary to ADE’s position.

ADE, though, points to dependent claims 3, 4, 5, and 6 of the ’259 patent in support of its argument for a broad construction of the phrase “oblique zone.” ADE argues that the doctrine of claim differentiation requires the broader interpretation of claim 1 that it seeks. (D.I. 595 at 22.) The argument, however, ignores the Federal Circuit’s warning that, “[t]he dependent claim tail cannot wag the independent claim dog.” North Am. Vaccine, Inc., 7 F.3d at 1577. Again, ADE’s proposed construction of “oblique zone” was “disclaimed” by the inventors during patent prosecution in their effort to distinguish the Quackenbos and Wells references cited by the examiner. (See, e.g., D.I. 627 at ’259 Patent Prosecution History, Applicants’ Response to Office Action mailed June 5, 1998 at 2-8 ( “Quackenbos and Wells wholly fail to teach or even remotely suggest the importance of ... collecting scattered light in the backward, center, and forward-scattered regions, and comparing the intensities in these three regions to discriminate pits from particles.”).)

The Court, therefore, adopts the magistrate judge’s construction of “oblique zone” and will also apply it to the claims of the ’259 patent. Accordingly, “oblique zone” means a collection zone that differs in polar angle from the central collection zone and that does not collect the same light being collected by the central zone but, instead, collects either forward or backward scattered light but does not collect both simultaneously. ADE’s objection to the magistrate judge