Wafer-Level Measurement of Thermal Conductivity on Thin Films

A method suited to perform wafer-level measurements of thermal conductivity on thin films by exploiting micromachined test structures is proposed. To this purpose, a measurement procedure able to compensate for instrumental offsets and sensitivity limits typically existing in a standard wafer-level electrical instrumentation, and to eliminate the influence of heat exchange through air is applied. In order to validate the technique, measurements on different thin films of interest in thermal MEMS fabrication are presented (LPCVD polycrys-talline silicon, evaporated aluminum, LPCVD silicon oxide).