A Two-Dimensional MEMS Scanning Mirror Using Hybrid Actuation Mechanisms With Low Operation Voltage

This paper presents the design, fabrication, and characterization of a novel CMOS-compatible 2-D MEMS scanning mirror based on hybrid actuation mechanisms. Both electrothermal and electromagnetic (EM) actuations have been integrated in the same device for slow and fast scanning purposes, respectively. The added advantage of a CMOS-compatible fabrication process allows our device to be monolithically integrated with CMOS integrated circuits. Optical deflection angles of ±1.5° for a 74-Hz vertical scan at 12 mW by electrothermal actuation and ±10° for a horizontal scan frequency of 202 Hz at 1.26 mA and 1 V_ac by EM actuation are reported. Our unique design of utilizing both electrothermal and EM actuation mechanisms is the first demonstration of such hybrid-driven CMOS-compatible MEMS mirror. Various Lissajous patterns have been demonstrated at low-power biasing condition, making our proposed hybrid actuation design approach suitable for mobile 2-D raster scanning applications powered by batteries with limited capacity.