A 5-V operated MEMS variable optical attenuator by SOI bulk micromachining

We report the design, fabrication, and successful demonstration of microelectromechanical variable optical attenuator (VOA) using an electrostatic microtorsion mirror (0.6 mm in diameter) combined with a fiber-optic collimator. The VOA operates at low voltages (dc 5 V or less) for large optical attenuation (40 dB, corresponding to mirror angle of 0.3/spl deg/) and a fast response time (5 ms or faster). The mirror made of a bulk-micromachined silicon-on-insulator wafer has been designed to be shock resistant up to 500 G without any mechanical failure. We also have suppressed temperature dependence of optical performance to be less than /spl plusmn/0.5 dB at 10-dB attenuation in the range of -5/spl deg/C-70/spl deg/C by mechanically decoupling the parasitic bimorph effect from the electrostatic operation.

[1]  K. Chawla,et al.  Mechanical Behavior of Materials , 1998 .

[2]  J.A. Walker,et al.  Dynamic spectral power equalization using micro-opto-mechanics , 1998, IEEE Photonics Technology Letters.

[3]  H. Toshiyoshi,et al.  Micromechanical tunneling probes and actuators on a silicon chip , 1999, Digest of Papers. Microprocesses and Nanotechnology '99. 1999 International Microprocesses and Nanotechnology Conference.

[4]  Won Hyo Kim,et al.  Optical characteristics of a micromachined VOA using successive partial transmission in a silicon optical leaker , 2002, IEEE/LEOS International Conference on Optical MEMs.

[5]  Ming C. Wu,et al.  Linearization of electrostatically actuated surface micromachined 2-D optical scanner , 2001 .

[6]  Clinton Randy Giles,et al.  Low insertion loss packaged and fibre connectorised MEMS reflective optical switch , 1998 .

[7]  Hans Peter Herzig,et al.  Applications of SOI-based optical MEMS , 2002 .

[8]  H. Fujita,et al.  Electrostatic micro torsion mirrors for an optical switch matrix , 1996 .

[9]  Chang-Hyeon Ji,et al.  Electromagnetic variable optical attenuator , 2002, IEEE/LEOS International Conference on Optical MEMs.

[10]  C. Marxer,et al.  Comparison of MEMS variable optical attenuator designs , 2002, IEEE/LEOS International Conference on Optical MEMs.

[11]  Yong-Kweon Kim,et al.  MEMS reflective type variable optical attenuator using off-axis misalignment , 2002, IEEE/LEOS International Conference on Optical MEMs.