A bulk-micromachined silicon micromirror for tunable optical switch applications

A bulk-micromachined electrostatic micromirror has been presented for tunable optical switching devices. A silicon micromirror with (111) crystalline planes has been fabricated. It measures 1000 /spl mu/m/spl times/400 /spl mu/m/spl times/90 /spl mu/m. The optical switching function has been obtained by an electrostatic drive of the micromirror in the direction parallel to the substrate. In a static performance test, stable deflection of the micromirror has been observed up to the threshold deflection of 26.5 /spl mu/m with the threshold voltage of 330 V. In a dynamic test, the resonant switching frequency has been measured as 590 kHz. For the DC bias voltage range of 50-300 V with an AC drive voltage of 10 V, a continuous reduction of the resonant switching frequency has been demonstrated with the maximum frequency reduction of 23.7%.