Surface Acoustic Wave Linear Motor Using Segment-Structured Diamond-Like Carbon Films on Contact Surface (1st Report)

Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high force, high speed and precise positioning. On the other hand, the motor has a problem with wear of contact surface. The SAW linear motor consist of a LiNbO3 as a stator transducer and a silicon substrate with distributed projections as a slider. However, the stator transducer material is easy to wear out due to friction drive. Moreover the silicon projections enhanced wearing. Lifetime of the motor is reduced by the wear of the stator. To solve this problem, the silicon substrate with segment structured diamond-like carbon (S-DLC) films is applied as the slider instead of the silicon slider with projections. The films are expected to increase abrasion-resistant performance of contact surface and acquire the same driving characteristics as the conventional silicon slider. This report presents installation of the films on the slider surface and successful work of the motor. Observation of its performance is also indicated to be compared with the conventional one. The films deposition on a stator transducer is introduced. Successful driving of the motor with the stator transducer is also described.