Micromirror truss structure and fabrication method

A micromirror device, comprising:

• an outer frame portion;
• a rotational gimbal portion hinged to the frame portion and moveable relative to the frame portion about a first axis;
• an inner rotational mirror portion having a reflective upper face surface hinged to the gimbal portion for movement of the mirror portion relative to the gimbal portion about a second axis;
• and
• a plurality of truss members disposed beneath the inner rotational mirror portion and the gimbal portion, wherein at least the gimbal portion and mirror portion are formed from a single piece of material.

A method of manufacturing a micromirror device, the method comprising:

• providing a silicon on insulator (SOI) wafer having a first layer bonded to a second layer, a thin oxide layer being disposed between the first and second layers, wherein the second layer is thicker than the first layer;
• removing a portion of the second layer to define a truss member height in the second layer;
• patterning and etching the truss member height defined areas of the second layer to form a plurality of truss members;
• and
• patterning and etching the first layer to form a frame portion, a gimbal portion disposed within the frame portion, and a mirror portion disposed within the gimbal portion.