Formation of Metal Interconnects and Their Resistancechange Behavior during Tensile Stretching for Stretchable Packaging Applications
Authors: Donghyun Park, Dae Ung Park, Kee-Sun Han, Soo Jin Shin, Hyun-Ah Oh, Tae Sung Oh, Ph.D. and Jung-Yeol Choi, Ph.D. Company: Hongik University and SK Hynix Date Published: 1/25/2016
Pan Pacific Symposium
Abstract: We examined the resistance-change behavior of thin Pt and Au films on the PDMS elastomeric substrate. A maximum Young’s modulus of 1.74 MPa was obtained for the PDMS substrate by adjusting the mixing ratio between base polymer and its curing agent to 10:1. Parylene coating on the PDMS surface was effective as an adhesion layer between metal interconnects and PDMS substrate. Without a Parylene coating, the resistance of a 150 nm-thick Pt film increased from 18.7 ohms to 3000 ohms with stretching to 20% strain and became open at strains larger than 20%. On the other hand, the resistance of a Pt film, sputtered on a Parylene-treated PDMS, was initially 10.3 ohms before loading, increased to 99.3 ohms at 30% elongation, and then decreased to 23.8 ohms after complete unloading. Thin Au metallization has better resistance properties for stretchable interconnect applications than Pt thin film. The resistance of a 150 nmthick Au film on a Parylene-coated PDMS substrate was 1.3 ohms before loading, increased to 19 ohms at 30% elongation, and then returned to 1.3 ohms after complete unloading.
Stretchable Packaging, Flexible Packaging, PDMS, Parylene Coating, Pt Film, Au Film