Method and apparatus for thermally actuated self testing of silicon structures

A method of testing a machined silicon structure, said silicon structure including at least one flexure beam means for permitting one portion of said silicon structure to move relative to another portion of said silicon structure in a flexure direction, said flexure beam means having a neutral axis, said silicon structure having a means for providing an output when flexed, said silicon structure including at least one thermal actuator beam having an axis of expansion and a length connecting said one portion of said silicon structure with said another portion of said silicon structure, said axis of expansion of said thermal actuator beam displaced from said neutral axis of said flexure beam means in a direction parallel to said flexure direction, said method comprising the steps of:

• changing said length of said at least one thermal actuator beam thereby displacing said another portion with respect to said one portion and flexing said flexure beam;
• and
• comparing said flexure beam output when flexed to a value and indicating the operability of said means for providing an output, wherein said means for providing an output comprises a piezoresistive portion of said flexure beam means, and said comparing step includes comparing resistance of said piezoresistive portion with a fixed value of resistance, wherein said silicon structure comprises a pressure sensor and said one portion of said silicon structure is a diaphragm and said another portion of said silicon structure is a support frame, said flexure beam means comprises a silicon structure surrounding a periphery of said diaphragm and connecting said diaphragm periphery to said support frame, said changing step includes displacing said diaphragm with respect to said support frame.