Fabrication and dynamic testing of electrostatic actuators with p⁺ silicon diaphragms

This paper presents the fabrication and testing of electrostatic actuators with p⁺ diaphragms. The actuators consist of two counter electrodes which are fabricated on a silicon wafer and Pyrex glass, respectively. The p⁺ diaphragm is used as a moving electrode, whereas the aluminium layer deposited on #7740 Pyrex glass is used as a fixed electrode. According to the calculation of static deflection of diaphragms with residual tensile stress, corrugated diaphragms deflect more than a flat one in most deflection regions. The dynamic characteristics of an actuator with a corrugated diaphragm and one with a flat diaphragm are tested and compared with the calculation results.