Control of Stress in Multilayered MEMS Devices

Stress issue in multilayered thin film structures has been investigated in the example of RF MEMS switches. Although a sandwiched thin film structure in theory can offset the stress-induced bending of a cantilever beam, it rarely possible to realize such offset because of the complexity in thin film deposition processes. Computer modeling and experiments have been conducted to reduce the unbalance of stress in a sandwiched thin film structure. It has demonstrated that a balance of stress and bending can be achieved by fine adjustment of the thickness of top layer of thin film