Design and fabrication of a micromirror using silicon bulk micromachining for out-of-plane right angle reflection

A matter of prime importance in silicon micromirror fabrication is how to get a silicon mirror plate under structure and fabrication restrictions. Deep silicon etch, silicon-glass anodic bonding and thinning process are used in this research for a silicon mirror plate. This approach offers a flat silicon mirror plate and the thickness of a silicon plate can be thinned up to 25 /spl mu/m. The micromirror should rotate with 45 degrees for out-of-plane right angle reflection. Therefore it is difficult to use stiff materials as a torsional spring. Aluminum is a good candidate for such a large angular motion though its residual stress may also affect operation performances.