PTAB

IPR2014-01009

GoerTek Inc v. Knowles Electronics LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Silicon Condenser Microphone and Manufacturing Method
  • Brief Description: The ’049 patent discloses a package for a silicon condenser microphone and a corresponding method for its manufacture. The core technology is an electromagnetic interference (EMI) shield created by electrically connecting a conductive layer in a multi-layer substrate to a conductive layer in a cover that encloses the microphone.

3. Grounds for Unpatentability

Ground 1: Claims 1, 15-16, and 19 are anticipated by Halteren under 35 U.S.C. § 102.

  • Prior Art Relied Upon: Halteren (Patent 6,324,907).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Halteren disclosed every limitation of the challenged apparatus claims. Specifically, Halteren taught a complete silicon condenser microphone package housing formed by a conductive metal lid (70) attached to a multi-layer substrate member (40), creating an internal cavity (75). The substrate was described as a "printed circuit board" with non-conductive Kapton and conductive copper layers. Halteren explicitly stated that its conductive lid is electrically connected to conductors in the substrate to provide EMI shielding for the enclosed microphone die (61).

Ground 2: Claims 1, 15-16, and 19 are obvious over Une in view of Halteren under 35 U.S.C. § 103.

  • Prior Art Relied Upon: Une (Patent 6,594,369) and Halteren (Patent 6,324,907).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Une disclosed a microphone package with nearly all claimed structural elements. This included a multi-layer substrate ("casing 1") with conductive paths and a metal cover (2) that are conductively bonded to provide an EMI shield against high-frequency waves. However, Une's microphone was an electret condenser microphone. Halteren was argued to supply the sole missing element: a silicon condenser microphone die, which it disclosed in a similar package configuration.
    • Motivation to Combine: A POSITA would combine these references because both were directed to designing small, mountable microphone packages for consumer electronics like hearing aids and cell phones. Petitioner argued it would have been an obvious and simple substitution to replace Une’s electret microphone with Halteren’s well-known silicon condenser microphone to create a desirable product: an EMI-shielded silicon microphone package.
    • Expectation of Success: The substitution was argued to be a minor engineering change that would yield predictable results. Une's package already provided the necessary structure and EMI shielding, and placing Halteren's microphone within Une's cavity would pose no technical challenges.

Ground 3: Claims 21-23, 25, and 26 are obvious over Carpenter in view of Baumhauer under 35 U.S.C. § 103.

  • Prior Art Relied Upon: Carpenter (Patent 6,928,718) and Baumhauer (Patent 4,533,795).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner contended that Carpenter disclosed a standard batch manufacturing method for electronic devices (Surface Acoustic Wave or “SAW” devices) that taught nearly all steps of method claim 21. This included providing a panel of interconnected ceramic substrates with conductive layers, attaching individual conductive lids over cavities to provide EMI protection, and finally singulating the panel. The only step Carpenter did not explicitly teach was attaching a silicon condenser microphone die. Baumhauer was asserted to teach this missing element, disclosing a complete silicon condenser microphone in a similar EMI-shielded package.
    • Motivation to Combine: A POSITA seeking an efficient, low-cost manufacturing method for Baumhauer's microphone would have been motivated to adopt Carpenter's established batch processing techniques. Carpenter itself expressly recognized its methods were applicable to various "microelectronic components," not just SAW devices. The combination was presented as the routine application of a known manufacturing process to a known component to achieve predictable cost and production efficiencies.
    • Expectation of Success: Petitioner argued that substituting Baumhauer's microphone for Carpenter's SAW die was a predictable modification, as the die-attach and bonding processes were similar and well within the skill of a POSITA.

  • Additional Grounds: Petitioner asserted numerous other grounds, including anticipation of claims 1, 15-16, and 19 by Baumhauer. Further obviousness challenges for the apparatus claims were based on combinations such as Sjursen/Baumhauer and Watabe/Hietanen. Additional challenges to the method claims were based on Une/Halteren (with and without Hyoudo) and Carpenter/Baumhauer (with Hyoudo), all relying on similar theories of substituting known microphone types into known EMI-shielded packages or manufacturing processes.

4. Key Technical Contentions (Beyond Claim Construction)

  • Technology is Not Novel: A central contention underlying all grounds was that the claimed EMI shielding technique—electrically connecting conductive layers in a substrate and cover—was a fundamental, decades-old concept in semiconductor packaging. Petitioner argued the ’049 patent claimed no novel concepts and merely applied this well-understood shielding principle to a standard microphone package.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1, 15-16, 19, 21-23, 25-26 as unpatentable.