Ion irradiation effects on the mechanical stability of compressed metallic thin films

Abstract

Residual stresses in materials and components such as thin films in microelectromechanical systems are developed during the production process and may drastically limit their functionality and lifetime; their minimization is thus of utmost technical importance. Ion beam irradiation in polycrystalline Mo thin films sputter-deposited on (100) silicon wafer at room temperature has been used to reduce the residual stresses present in the layer and thus to improve the mechanical stability of the film/substrate set. Although a strong reduction of residual stresses in the whole film is evidenced, irradiation affects the film-substrate bond strength; defect creation at the film-substrate interface due to ion implantation induces thin-film delamination.