The Federal Circuit upheld the PTAB’s decision deeming an integrated circuit connector patent unpatentable for obviousness, despite concluding that the Board’s claim construction was erroneous. The Court also rejected a challenge to the Board’s motivation to combine findings as to certain dependent claims, concluding that the Board provided a “thorough and well-reasoned explanation,” relying on the testimony of Microchip’s expert.
Microchip Technology, Inc. had petitioned for inter partes review, arguing that all claims of HD Silicon Solutions LLC’s (“HDSS”) ’033 patent were rendered obvious by the “Trivedi” reference. The ’033 patent was directed to a local interconnect layer in an integrated circuit. The key claim limitation required “depositing a second film … comprising tungsten.”
The parties disputed the construction of “comprising tungsten” before the PTAB. HDSS, the patent owner, argued for a narrow construction that would limit the term to elemental tungsten. The Board, however, agreed with Microchip Technology, construed the term broadly to mean “any form of tungsten, including both elemental tungsten and tungsten compounds,” and found the claims obvious.
HDSS argued on appeal that the Board improperly construed “comprising tungsten.” The Federal Circuit agreed, but determined the Board’s error was harmless and upheld the decision. The Court found substantial evidence supported the Board’s alternative finding that Trivedi disclosed both tungsten silicide and elemental tungsten layers, with either rendering the claims obvious. Thus, despite the claim construction error, the Board’s conclusion stood because the Trivedi reference still disclosed sufficient material to render the claims obvious.
