PTAB

IPR2018-01022

II VI Inc v. Saint Gobain Ceramics & Plastics Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Single Crystals and Methods for Fabricating Same
  • Brief Description: The ’469 patent relates to large-sized single crystal sapphire sheets and the methods and equipment for their fabrication. The claims recite specific dimensions for the sheets, including width, thickness, variation in thickness, and the geometry of transition points from a neck to a main body.

3. Grounds for Unpatentability

Ground 1: Anticipation over Patel - Claims 1-2, 4, 25-27, and 33-38 are anticipated under 35 U.S.C. §102(b) by the Patel article.

  • Prior Art Relied Upon: Patel (an article titled “Transparent Armor,” AMPTIAC Newsletter, Fall 2000).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the Patel article expressly disclosed every limitation of the challenged claims. Patel described a transparent sapphire sheet produced using an edge-defined growth technique with a length of 15 inches (38.1 cm), a width of 12 inches (30.48 cm), and a thickness of 0.25 inches (0.635 cm). These dimensions satisfied the limitations of independent claims 1 and 33, which required a width of at least 28 cm and a thickness of at least 0.5 cm. The dimensions disclosed in Patel also met the more specific requirements of the challenged dependent claims.

Ground 2: Obviousness over Harris, LaBelle, and Chalmers/LaBelle - Claims 11-14, 16, and 21-24 are obvious over the Harris article in view of LaBelle ’636 and the Chalmers/LaBelle article.

  • Prior Art Relied Upon: Harris (a 1999 article titled "Materials for Infrared Windows and Domes"), LaBelle ’636 (Patent 3,701,636), and Chalmers/LaBelle (a 1971 article on Edge-Defined, Film-Fed Crystal Growth).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Harris disclosed a large, flat sapphire sheet (30 cm wide x 46 cm long) produced by the Edge-defined, Film-fed Growth (EFG) method. A figure in Harris explicitly showed the claimed structural features of independent claim 11: an as-grown sheet with a neck, a main body with parallel sides, and a transition between the neck and main body. LaBelle ’636 and Chalmers/LaBelle provided the underlying technical principles of the EFG process.
    • Motivation to Combine: A POSITA would combine these references to produce large, high-quality sapphire sheets. Harris showed the desired product, while LaBelle ’636 and Chalmers/LaBelle taught the fundamental process controls necessary to achieve it. Specifically, these references explained that minimizing temperature gradients across the die is critical for stable crystal growth.
    • Expectation of Success: Petitioner argued the claimed transition distance (ΔT), which is a proxy for the temperature gradient across the die, was a known design parameter. A POSITA would have been motivated to minimize this gradient to achieve the stable growth of a large sheet as shown in Harris. Therefore, achieving the claimed ΔT values of not greater than 4.0 cm, 3.0 cm, and 2.0 cm would have been an obvious and expected outcome of applying known process control principles to the EFG method.

Ground 3: Obviousness over Patel, LaBelle, and Chalmers/LaBelle - Claims 6-9, 17-20, 29-32, and 40-43 are obvious over Patel in view of LaBelle ’636, LaBelle ’348 and the Chalmers/LaBelle article.

  • Prior Art Relied Upon: Patel (the "Transparent Armor" article), LaBelle ’636 (Patent 3,701,636), LaBelle ’348 (Patent 3,591,348), and Chalmers/LaBelle (the 1971 article).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground addressed claims requiring specific, low variations in thickness (e.g., not greater than 0.2 cm). While Patel disclosed the basic sheet dimensions, it did not specify thickness variation. LaBelle ’348 and LaBelle ’636 taught methods for growing crystalline bodies with exceptionally smooth and flat surfaces. LaBelle ’348 stated that ribbons grown with its method have surfaces smooth to within a maximum deviation of about 1000 angstroms (10⁻⁵ cm), a value far smaller than the claimed limitations.
    • Motivation to Combine: A POSITA would combine the teachings to improve the quality and surface uniformity of the large sapphire sheets described in Patel. Achieving a smooth, uniform thickness is an inherent goal in crystal growth for optical applications like transparent armor.
    • Expectation of Success: Because LaBelle ’348 and LaBelle ’636 taught that the EFG process, when properly controlled, inherently produces sheets with extremely flat surfaces and minimal thickness variation, a POSITA would have had a high expectation of success in producing a sheet meeting the claimed thickness uniformity limitations. The claimed values represented a level of quality that was an obvious design goal readily achievable with known techniques.

  • Additional Grounds: Petitioner asserted additional obviousness challenges, including grounds that the Patel article combined with the Locher article and LaBelle ’636 rendered claims obvious, and a separate ground based on a Saint-Gobain brochure in view of multiple secondary references.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §325(d) would be inappropriate, particularly regarding the ground based on the Saint-Gobain brochure. Although the Patent Owner had submitted the brochure during a prior Ex Parte Reexamination, the Examiner only considered it for anticipation and ultimately withdrew the rejection based on a finding of non-enablement. Petitioner contended that its proposed obviousness ground, which combined the brochure with multiple other references to supply the enabling details of the EFG process, presented arguments and a combination of art that the USPTO had never previously considered.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-2, 4-9, 11-14, and 16-44 of the ’469 patent as unpatentable.