Thermal microactuators for optical purpose

The core of the project was to design a moveable micromirror array with the most optimal dependence of the optically active area, the deflection angles and the micromirror power consumption. The matrix of 10×20 micromirrors uses a thermal actuated principle. The micromirror was designed using an industrial 0.8 μm double metal CMOS process followed by one single postprocessing step and anisotropic silicon etch. The device consists of one cantilever beam supporting the mirror plate. The beam is a bimorph sandwich of aluminium and silicon dioxide enclosing polysilicon heating resistor. The control electronics contains 20-bit edge-triggered shift register with serial data entry and an output from each of the twenty stages (flip-flop). The output buffer is a driver for the CMOS switch (transfergate) which connects current (Pad Supply for the beam) to the thermal actuator (beam). The ANSYS program was used for the mechanical simulation of thermally actuated micromirror