This paper reports the design, fabrication and characterization process of the trapezoidal Electrostatic Comb-drive Actuator (ECA) with the slope angle α = 2◦ . Together with the trapezoidal ones, the rectangular ECA with identical dimension was also designed and fabricated for comparison purpose. In order to reduce calculating deviation, the fringing effect was also taken into consider while carrying out theoretical analysis. | Vietnam Journal of Mechanics, VAST, Vol. 34, No. 4 (2012), pp. 261 – 269 DESIGN AND FABRICATION OF THE TRAPEZOIDAL ELECTROSTATIC COMB-DRIVE ACTUATOR Pham Hong Phuc1 , Dinh Khac Toan1 , Dang Bao Lam1 , Nguyen Tuan Khoa1 , Nguyen Tien Dung2 1 Hanoi University of Science and Technology, Vietnam 2 Thai Nguyen University of Technology, Vietnam Abstract. This paper reports the design, fabrication and characterization process of the trapezoidal Electrostatic Comb-drive Actuator (ECA) with the slope angle α = 2◦ . Together with the trapezoidal ones, the rectangular ECA with identical dimension was also designed and fabricated for comparison purpose. In order to reduce calculating deviation, the fringing effect was also taken into consider while carrying out theoretical analysis. The obtained results pointed out the fact, that the trapezoidal ECA excels the rectangular ones with the same numbers of teeth in electrostatic force and displacement generation, while requires relatively low driving voltage. But it is also observed that with higher driving voltage (larger than 50 V), the trapezoidal ECA starts to lose its stability (the lateral pull-in phenomenon occurs). Keyword: electrostatic comb-drive actuator. 1. INTRODUCTION A rectangular electrostatic comb-drive actuator (ECA) was firstly introduced by Tang et al. [1]. While working, the fabrication errors can cause imbalance of the forces acting on the electrodes, which can lead to destabilization of the rectangular ECA [2]. Impact of destabilization increases with a thinner finger thickness and lower stiffness of the beam of the actuator. On the other hand, for overcoming this problem, choosing larger size of the electrodes could also lead to bulky dimension of the whole system. In [3], Johan B. C. Engelen et al. mentioned about the optimized shape of the ECAs. After optimization, the ECA can generate larger and constant electrostatic force. With the same number of fingers in a length unit, the ECA with optimized teeth
