A Two-Axis MEMS Scanner Driven by Radial Vertical Combdrive Actuators

We report a two-axis MEMS scanner driven by radial vertical combdrive actuators. The device is fabricated by a five-layer polysilicon surface micromachining process. A cross-bar spring structure consisting of lower and upper torsion springs is designed to achieve two rotational degrees of freedom, enabling the dual-axis rotation. Both the vertical comdrive actuators and the torsion springs are hidden underneath the mirror to achieve a small form factor. Mechanical rotation angles of plusmn5.4deg at 42 V and plusmn2.4deg at 63 V are obtained for rotation about the lower and upper springs, respectively.