Abstract
A thin film polyimide diaphragm for a MEMS actuator is investigated on process and mechanical characteristics. According to the low elastic modulus and the thin film process, a thin film polyimide diaphragm has a possibility to become an actuator producing large displacement. In the process, spin coating is used for making a thin film of polyamide. Then the polyamide turns into polyimide by baking. For the diaphragm, deep-RIE (Bosch process) is used to remove a silicon substrate. We are able to process the thin film diaphragm with the thickness down to 2μm in this method. To use the diaphragm as an actuator, we choose heat expansion as a driving method. Aluminum thin film is deposited on the diaphragm for applying an electric current. It is confirmed that this system works as an actuator by controlling a current.
