DYNAMIC ACTUATION OF POLYIMIDE V-GROOVE JOINTS BY ELECTRICAL HEATING

New robust three-dimensional silicon structures with integrated heater s for dynamic actuation have been fabricated and tested. The structure s can be used in both static and dynamic modes for 3-D sensor and actu ator applications. The proposed technique for bending 3-D structures o ut of the wafer plane is based on thermal shrinkage of polyimide in V- grooves, producing static bending. This static angle can be chosen in a wide range by varying the curing temperature. The relatively large t hermal expansion of polyimide makes it possible to use the structure i n dynamic mode. A local power dissipation in the joint is achieved by using a current through an integrated heater. This makes it possible t o control the bending angle of each individual structure. For the test ed polyimide V-groove joints, static bending angles of 35 degrees and dynamic angles of 3 degrees per V-groove have been achieved. (C) 1998 Elsevier Science S.A. All rights reserved.