Design of a high-speed electrothermal linear micromotor for microelectromechanical systems safety-and-arming devices

The design, fabrication and characterisation of a high-speed electrothermal linear micromotor for microelectromechanical systems safety-andarming devices are presented. The micromotor consists of a microspring, a barrier plate and four V-shaped electrothermal actuators with microlever amplifications. The whole device is fabricated on a silicon-on-insulator wafer with a 50 μm device layer and the fabrication process is introduced. The micromotor has been successfully operated at a speed of 35.66 mm/s over a range of 500 μm with an output force of 5.27 mN under the applied voltage of 23 V. The chip area of the fabricated micromotor is about 19.20 mm2, which means the micromotor can be easily integrated with other microdevices. The linear micromotor performs well in driving force, mechanical strength and working speed, which signifies the proposed device is suitable for safety-and-arming devices.