Fabrication of micro temperature sensor on the flexible substrate

Abstract

In this study, micro flexible temperature sensor arrays were designed and fabricated on parylene thin film. The flexible parylene thin film was inserted into the micro temperature sensors using the micro-electro-mechanical-systems (MEMS) fabrication process. The flexible micro sensor array was covered with two pieces of parylene thin film that was etched by reactive ion etching (RIE) to uncover the contact pad. Finally, the silicon wafer was segmented and then soaked in acetone to remove the flexible temperature sensor from the silicon substrate. In fabricating the thin films, Au and Cr resistive temperature sensor arrays with Al conducting lines, the Cr was formed the adhesion layer between parylene and Au. The thickness of parylene and the micro temperature sensor was 2 mum. They could therefore be easily attached to curved surfaces. The thin film sensors were highly sensitive (4.44times10-3/degC) to temperature and were effective at temperatures of up to 100degC. This study verified the feasibility of thin film sensor array applications with flexible parylene-base.