Stretchable Electronics for Reusable Multichannel Skin Patch and High Fill Factor Display

Abstract

Stretchable electronics has versatile application fields including skin attachable healthcare monitoring sensors, shape changeable visualization tools, energy harvesting devices, sensory aid or prosthetic devices, and wearable electronic clothes. Applying the geometric structure of non-stretchable materials for stretchable interconnect is one prospective method to realize stretchable electronics. This approach is highly applicable to MEMS fabricated components and the fabricated devices have stable electrical connection with high durability. This dissertation proposes geometric structure-based stretchable electronics design strategies and fabrication processes to realize practical applications including stretchable, reusable, large areal covering, multichannel surface electromyography (EMG) sensors and stretchable, high fill factor, double layer structured, inorganic light emitting diode (LED) display. With the design of the stiff “frame” structure and the highly stretchable “interconnect” structure, the proposed EMG sensor can be stretchable and reusable in the skin attachable form. The sensor has multichannel with large areal coverage that can cover multiple muscles for simultaneous acquisition of multiple EMG signals. In addition, the double layer structure design and fabrication process enables high fill factor stretchable display with LED resolution control capability and strain isolation characteristic. The stretchable display stably operated in a passive matrix addressing method while it is freely deform in stretching, bending, and twisting shape. This dissertation explores and proposes unconventional design strategies of stretchable electronics for futuristic applications and provides the computational and experimental analysis of stretchable devices using geometric structure-based stretchable interconnect approach. It has potential to improve its efficiency and productivity comparable or superior to conventional electronic devices by further optimization in design and fabrication processes.