A Fast, Large-Stroke Electrothermal MEMS Mirror Based on Cu/W Bimorph

Micromachines

Xiaoyang Zhang²  Liang Zhou²  Huikai Xie¹ 

[1] Department of Electrical & Computer Engineering, University of Florida, Gainesville, FL 32611, USA

关键词: microelectromechanical systems (MEMS) mirror;    electrothermal actuation;    Cu/W bimorph;    lateral-shift-free (LSF);    vertical scan;    multimorph frame;    large range;    fast response;    backside release;   

DOI  :  10.3390/mi6121460

来源: mdpi

【 摘 要 】

This paper reports a large-range electrothermal bimorph microelectromechanical systems (MEMS) mirror with fast thermal response. The actuator of the MEMS mirror is made of three segments of Cu/W bimorphs for lateral shift cancelation and two segments of multimorph beams for obtaining large vertical displacement from the angular motion of the bimorphs. The W layer is also used as the embedded heater. The silicon underneath the entire actuator is completely removed using a unique backside deep-reactive-ion-etching DRIE release process, leading to improved thermal response speed and front-side mirror surface protection. This MEMS mirror can perform both piston and tip-tilt motion. The mirror generates large pure vertical displacement up to 320 μm at only 3 V with a power consumption of 56 mW for each actuator. The maximum optical scan angle achieved is ±18° at 3 V. The measured thermal response time is 15.4 ms and the mechanical resonances of piston and tip-tilt modes are 550 Hz and 832 Hz, respectively.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.