Flash-evaporated TiNiCu thick film for shape memory alloy micro actuator

In order to realize flexible micro actuators with a high operational force, TiNiCu shape memory alloy (SMA) films with thickness exceeding 10 mu m were fabricated by flash-evaporation. The addition of a small amount of copper to the films with TiNi main composition provided fine and compact crystallographic structures followed by high flexibility, while actuation force increased with increasing thickness. These thick films will be applied to medical MEMS devices, such as active catheters and meandering spring actuators. (C) 2008 Elsevier B.V. All rights reserved.