PTAB

IPR2018-00333

Seoul Semiconductor Co Ltd v. Document Security Systems Inc

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Key Events
Petition

1. Case Identification

2. Patent Overview

  • Title: Packaging Device For Semiconductor Die, Semiconductor Device Incorporating Same And Method Of Making Same
  • Brief Description: The ’486 patent describes a semiconductor packaging device, particularly for light-emitting diodes (LEDs), intended to improve packing density. The invention uses a substantially planar substrate with conductive pads on its top and bottom surfaces, which are electrically connected by an interconnecting element extending through the substrate.

3. Grounds for Unpatentability

Ground 1: Obviousness over Rohm in view of Kish - Claims 1-3

  • Prior Art Relied Upon: Rohm (Japanese Patent Application Publication No. 2003-17754) and Kish (Patent 5,376,580).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Rohm, which describes a "Surface Mount Type Semiconductor Device," discloses every element of the challenged claims. Rohm taught a semiconductor device with a planar substrate, an electrically conductive mounting pad (die bonding electrode) on the top surface for an LED, a connecting pad (surface mount electrode) on the bottom surface, and a conductive interconnecting element extending through the substrate to connect the top mounting pad and bottom connecting pad. For dependent claim 2, Rohm disclosed a second bonding pad on the top surface connected by a bonding wire to the LED's top surface electrode. However, Rohm did not explicitly state that the LED's top and bottom electrodes were "metallized."
    • Motivation to Combine: Petitioner asserted that while Rohm's disclosure of an "electrode" inherently suggests a conductive material, any ambiguity is resolved by Kish. Kish, which describes wafer bonding of LED layers, explicitly taught the use of "metallized electrodes" on the top and bottom surfaces of LEDs as a "standard" and well-known technique. A person of ordinary skill in the art (POSITA) would combine the standard metallized LED electrodes of Kish with the packaging structure of Rohm to ensure proper, reliable electrical connections for the LED, which was a predictable and fundamental requirement for device operation.
    • Expectation of Success: A POSITA would have had a high expectation of success because implementing electrodes using metal was a standard, well-understood, and necessary technique for providing power to LEDs. The ’486 patent itself acknowledged that metallization layers were part of conventional prior art.

Ground 2: Obviousness over Matsushita in view of Edmond 589 - Claims 1-3

  • Prior Art Relied Upon: Matsushita (Japanese Patent Application Publication No. 2001-352102) and Edmond 589 (Patent 5,523,589).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that Matsushita disclosed the claimed packaging structure for a vertical LED. Matsushita taught a planar substrate, a mounting pad on the top surface (top portion of electrode 3), a connecting pad on the bottom surface (bottom portion of electrode 3), and an interconnect element connecting them through the substrate. Matsushita also showed an LED mounted on the top pad. However, like Rohm, Matsushita did not provide specific details on the metallization of the vertical LED's contact surfaces.
    • Motivation to Combine: To supply the missing teaching of metallized surfaces, Petitioner relied on Edmond 589. Edmond 589 disclosed a vertical geometry LED with metallized ohmic contacts on its top and bottom surfaces, formed from metals like aluminum, gold, or platinum. Petitioner argued a POSITA, seeking to implement the vertical LED package of Matsushita, would have naturally looked to known vertical LED structures like that in Edmond 589. Edmond 589 provided strong motivation by highlighting the advantages of its design, including improved brightness, efficiency, and longevity. A POSITA would combine the superior vertical LED of Edmond 589 with the compatible package of Matsushita to achieve these known benefits.
    • Expectation of Success: The combination of a known vertical LED component (Edmond 589) with a package designed for such a component (Matsushita) was a simple substitution of one known element for another to obtain predictable results. Therefore, a POSITA would have had a high expectation of success.

4. Key Claim Construction Positions

  • "metallized ... surface": Petitioner argued for the construction "a metal layer on at least a portion of the surface." This construction was asserted to be consistent with the patent's specification, which uses the term interchangeably with "metallization layer" and "electrode." This broad construction was critical for mapping prior art references that disclosed metal electrodes or contacts onto the claim language.
  • "the metallized top major surface comprises a first electrode ... and the metallized bottom major surface comprises a second electrode": For this limitation in claim 3, Petitioner proposed the construction "the metallized surfaces comprise electrical contacts to the LED." This functional interpretation was argued to be supported by the specification and necessary to give meaning to the term "electrode." This construction allowed Petitioner to argue that any prior art showing metallized electrical contacts on the top and bottom of an LED would satisfy the limitations of claim 3.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-3 of the ’486 patent as unpatentable under 35 U.S.C. §103.