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Stretchable Deformation-Resistance Characteristics of Metal Thin Films for Stretchable Interconnect Applications I. Effects of a Parylene F Intermediate Layer and PDMS Substrate Swelling

신축 전자패키지 배선용 금속박막의 신축변형-저항 특성 I. Parylene F 중간층 및 PDMS 기판의 Swelling에 의한 영향

  • Park, Donghyun (Department of Materials Science and Engineering, Hongik University) ;
  • Oh, Tae Sung (Department of Materials Science and Engineering, Hongik University)
  • 박동현 (홍익대학교 공과대학 신소재공학과) ;
  • 오태성 (홍익대학교 공과대학 신소재공학과)
  • Received : 2017.09.12
  • Accepted : 2017.09.25
  • Published : 2017.09.30

Abstract

We investigated the feasibility of parylene F usage as an intermediate layer between a polydimethylsiloxane (PDMS) substrate and an Au thin-film interconnect as well as the swelling effect of PDMS substrate on the stretchable deformability of an Au thin film. The 150-nm-thick Au film, which was sputtered on a PDMS substrate without a parylene F layer, exhibited an initial resistance of $11.7{\Omega}$ and an overflow of its resistance at a tensile strain of 12.5%. On the other hand, the Au film, which was formed with a 150-nm-thick parylene F layer, revealed an much improved resistance characteristics: $1.21{\Omega}$ as its initial resistance and $246{\Omega}$ at its 30% elongation state. With swelling of PDMS substrate, the resistance of an Au film substantially decreased to $14.4{\Omega}$ at 30% tensile strain.

Polydimethylsiloxane (PDMS) 신축기판과 Au 박막 사이의 중간층으로서 parylene F의 적용 가능성을 분석하고, Au 박막의 스퍼터링 중에 발생하는 PDMS 기판의 swelling이 Au 박막의 신축변형-저항 특성에 미치는 영향을 분석하였다. Parylene F 중간층 없이 PDMS 기판에 스퍼터링한 150 nm 두께의 Au 박막은 $11.7{\Omega}$의 초기저항을 나타내었으며, 12.5%의 인장변형률에서 저항의 overflow가 발생하였다. 반면에 150 nm 두께의 parylene F 중간층을 갖는 Au 박막의 초기저항은 $1.21{\Omega}$이었으며 30% 인장변형률에서 저항이 $246{\Omega}$으로 저항증가비가 현저히 낮아졌다. PDMS 기판의 swelling이 발생함에 따라 30% 인장변형률에서 Au 박막의 저항이 $14.4{\Omega}$으로 크게 저하되었다.

Keywords

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