2 DOF optical microscanner with large deflection angles

This paper reports on a novel microscanner with two degrees-of-freedom (DOF) fabricated from a shape memory alloy (SMA) thin film composite consisting of a three-layer system of Ti(Ni,Cu)/Mo/Fc(Cr,Ni). This three-layer system creates concave and convex curvatures upon heating and cooling, respectively, due to a strong change of bimorph stress mainly induced by a martensitic transformation. The resulting coupled thermal, mechanical and optical performance characteristics of Ti(Ni,Cu) thin films are deposited by DC-magnetron sputtering onto unheated Mo substrates, which exhibit a lower thermal expansion coefficient compared to TiNi-based alloys