MULTIPLE SOURCE DEPOSITION OF SHAPE-MEMORY ALLOY THIN FILMS

摘要

A method for simultaneously and controllably depositing multiple metals to create thin film alloys that have unique physical properties. In particular, the method involves the deposition of multiple alloy thin films with shape-memory effects, such as Ni-Ti-Cu. The Ni-Ti-Cu films were mixed-sputter deposited onto heated silicon substrates from individually powered Ni, Ti, and Cu targets, providing increased flexibility in film stoichiometry, and thus allowing for optimization of the shape-memory properties. The multiple metal films have particular application for micro actuators, such that actuation can be performed on miniature/micro devices with dimensions as small as 5νm x 5νm x 2νm, and can effectively operate in 250νm diameter areas. One application is for actuation of catheter/endoscopic-based medical devices for minimally-invasive surgical or therapeutic procedures. Another application is for use in miniaturized valves and pumps, or for cleaning of miniature pipes.