Wafer-level integration of NiTi shape memory alloy wires for the fabrication of microactuators using standard wire bonding technology

This paper reports on the first integration of SMA wires into silicon based MEMS structures using a standard wire bonder. This approach allows fast and efficient placement, alignment and mechanical attachment of NiTi-based SMA wires to silicon-based MEMS. The wires are mechanically anchored and clamped into deep-etched silicon structures on a wafer. The placement precision is high with an average deviation of 4 μm and the mechanical clamping is strong, allowing successful actuation of the SMA wires.