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IPR2021-01031

Intel Corp v. Demaray LLC

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petition

1. Case Identification

2. Patent Overview

  • Title: Pulsed DC Reactive Sputtering of Insulating Films
  • Brief Description: The ’657 patent discloses a method for depositing insulating films on a substrate using a reactive sputtering plasma reactor. The system uses a pulsed-DC power supply coupled to a sputtering target through a narrow band-rejection filter and a separate RF power supply to bias the substrate, with the filter preventing interference between the two supplies.

3. Grounds for Unpatentability

Ground 1: Claims 2-4, 6, 8, 10-12, and 21 are obvious over Barber in view of Hirose.

  • Prior Art Relied Upon: Barber (Patent 6,342,134) and Hirose (Patent 6,485,602).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Barber taught a reactive sputtering system for depositing insulating films (e.g., AlN) using a pulsed-DC power supply for the target and a separate RF power supply for biasing the substrate. Barber disclosed all major process steps of independent claim 2, including providing a process gas, applying pulsed-DC power, applying an RF bias, and providing a magnetic field. However, Barber did not expressly disclose a filter between its DC power supply and the target. Hirose taught a plasma processing apparatus with two different frequency power supplies, where a narrow band-rejection filter was used to prevent high-frequency current from one supply from interfering with and damaging the other.
    • Motivation to Combine: A POSITA would combine Hirose’s filter with Barber’s dual-supply system for the predictable purpose of preventing the RF power from the substrate bias supply from affecting or damaging the pulsed-DC target supply. Petitioner asserted this was a well-known problem with a known solution, pointing to manufacturer manuals that recommended using an AC blocking filter when a DC power supply is used in combination with an AC (RF) power supply. The systems in Barber (sputtering) and Hirose (reactive ion etching) were argued to be analogous plasma processing systems where such interference issues are common.
    • Expectation of Success: A POSITA would have had a high expectation of success, as implementing a known filter to solve a known interference problem in a similar plasma system was a routine design choice involving the application of known circuit design principles.

Ground 2: Claim 1 is obvious over Barber in view of Hirose and Sellers.

  • Prior Art Relied Upon: Barber (Patent 6,342,134), Hirose (Patent 6,485,602), and Sellers (Patent 5,651,865).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground incorporated the Barber and Hirose combination from Ground 1 to meet the majority of claim 1 limitations, which largely mirrored those of claim 2. The key additional limitation addressed was claim 1[f], "reconditioning the target; wherein reconditioning...includes reactive sputtering in the metallic mode and then reactive sputtering in the poison mode." While Barber described operating in both a metallic mode (low reactive gas flow) and a poison mode (high reactive gas flow), it did not explicitly label this process as "reconditioning." Sellers disclosed a target "conditioning" process (also known as "burn-in") using pulsed DC sputtering to sputter off oxides and impurities from a target after it has been exposed to the atmosphere, which would be a necessary step after chamber maintenance in a system like Barber's.
    • Motivation to Combine: A POSITA would have been motivated to incorporate the explicit target reconditioning step taught by Sellers into the Barber/Hirose system to ensure the deposition of high-quality films free from contaminants. Petitioner argued that after multiple depositions, the chamber in Barber would inevitably be vented for cleaning, exposing the target to contaminants and necessitating a reconditioning step as taught by Sellers to ensure process stability and film quality.
    • Expectation of Success: The combination was presented as the application of a known technique (target burn-in) to a standard sputtering system to achieve the predictable result of improved film purity and quality.

Ground 3: Claims 5 and 7 are obvious over Barber in view of Hirose and Dogheche.

  • Prior Art Relied Upon: Barber (Patent 6,342,134), Hirose (Patent 6,485,602), and Dogheche (a 1999 article in Applied Physics Letters).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground built upon the Barber/Hirose combination to address dependent claims requiring a "ceramic target" (claim 5) and holding the substrate temperature "substantially constant" (claim 7). Barber taught using a metallic target (aluminum). Dogheche was a publication describing the deposition of high-quality AlN films using a ceramic AlN target. Dogheche also taught that the "best texture" of the film was obtained by maintaining a constant substrate temperature (400 °C).
    • Motivation to Combine: A POSITA would have been motivated to substitute Barber's metallic target with Dogheche's ceramic target to expand the system's capability to deposit high-quality AlN films, which Dogheche noted were of "increasing interest" for optical/electronic applications. To achieve the high-quality results described in Dogheche, the POSITA would also have been motivated to incorporate its teaching of maintaining a constant substrate temperature during deposition.
    • Expectation of Success: A POSITA would have expected success in substituting a known target material and employing a known process control parameter (temperature stability) to achieve the known benefits of higher quality film deposition.

  • Additional Grounds: Petitioner asserted numerous additional grounds, primarily targeting other dependent claims. These grounds relied on the core Barber/Hirose combination in view of other references, such as Safi (for adjusting oxygen flow to control refractive index), Aokura (for linear magnet sweeping), Segal (for using alloyed and tiled targets), and Sill (for a specific filter bandwidth). Further grounds were asserted adding Belkind (a 2000 conference proceeding) to each of the foregoing combinations as an alternative argument for teaching that the pulsed-DC voltage must alternate between positive and negative values.

4. Key Technical Contentions (Beyond Claim Construction)

  • Petitioner's primary technical contention was that Barber's disclosure of a pulsed-DC power supply for reactive sputtering inherently taught or suggested that the voltage on the target alternates between negative (for sputtering) and positive (to discharge insulating layers and prevent arcing), even if not explicitly stated. As a fallback position, Petitioner argued that if Barber was found insufficient, Belkind explicitly taught using bipolar pulsed-DC power to avoid arcing during reactive sputtering and that it would have been obvious to apply Belkind's teachings to the Barber system.

5. Arguments Regarding Discretionary Denial

  • Against §325(d) Denial: Petitioner argued that while Belkind was cited in an Information Disclosure Statement (IDS) during prosecution, it was never used by the Examiner in a rejection, nor was it distinguished by the applicant. Therefore, the Examiner did not give it the substantive consideration that it is given in the Petition, and denial under §325(d) would be inappropriate.
  • Against §314(a) Fintiv Denial: Petitioner argued that the Fintiv factors weighed in favor of institution. It asserted that the co-pending district court litigations were in their infancy, with no trial dates set and minimal investment of resources by the court or parties. Petitioner also noted that the invalidity grounds and prior art asserted in the IPR were not completely overlapping with those in the district court, and that IPR would be a more efficient and expert forum to resolve the patentability questions.

6. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-21 of the ’657 patent as unpatentable.