Fabrication and characteristic evaluation of a rotary type SDA with a rotation angle measuring scale

Recently, there are a lot of studies on the micro motors using an electrostatic actuator as the driving force in the micro electro mechanical systems (MEMS) field. However, the electrostatic actuator has a problem concerning the precise actuation control. In the conventional researches, the rotary type electrostatic actuators have been reported, but the rotation angle has not been precisely controlled in the actuators. This paper describes a new micro motor by a rotary type scratch drive actuator (SDA) with a Poly-Si scale to measure the rotation angle based on the MEMS technology. In this study, we make it possible to measure the rotation angle of th rotary type SDA motor by a fiber type micro encoder. For this purpose, we formed the Poly-Si scale around the outside of the micro SDA motor, and achieved a reflection type optical fiber micro encoder. In this presentation, we describe the fabrication process for this device and the evaluation results of the optical characteristic of the fiber type micro encoder.