Journal of the Microelectronics and Packaging Society

Polydimethylsiloxane (PDMS)를 베이스 기판으로 사용하고 이보다 강성도가 높은 flexible printed circuit board (FPCB)를 island 기판으로 사용하여 island-bridge 구조의 soft PDMS/hard PDMS/FPCB 신축 패키지를 형성하고, 이의 유효 탄성계수와 변형거동을 분석하였다. 각기 탄성계수가 0.28 MPa, 1.74 MPa 및 1.85 GPa인 soft PDMS, hard PDMS, FPCB를 사용하여 형성한 soft PDMS/hard PDMS/FPCB 신축 패키지의 유효 탄성계수는 0.58 MPa로 분석되었 다. Soft PDMS/hard PDMS/FPCB 신축 패키지에서 soft PDMS의 변형률이 0.3이 되도록 인장시 hard PDMS와 FPCB 의 변형률은 각기 0.1과 0.003이었다.
A stiffness-gradient soft PDMS/hard PDMS/FPCB stretchable package of the island-bridge structure was processed using the polydimethylsiloxane (PDMS) as the base substrate and the more stiff flexible printed circuit board (FPCB) as the island substrate, and its effective elastic modulus and stretchable deformation characteristics were analyzed. With the elastic moduli of the soft PDMS, hard PDMS, and FPCB to be 0.28 MPa, 1.74 MPa, and 1.85 GPa, respectively, the effective elastic modulus of the soft PDMS/hard PDMS/FPCB package was analyzed as 0.58 MPa. When the soft PDMS of the soft PDMS/hard PDMS/FPCB package was stretched to a tensile strain of 0.3, the strains occurring at hard PDMS and FPCB were found to be 0.1 and 0.003, respectively.

Keywords stretchable package, stretchable substrate, PDMS, FPCB, elastic modulus, stretchable deformation