Residual stress and fracture of thick dielectric films for power MEMS applications

This paper presents residual stress characterization and fracture analysis of thick PECVD oxide films. The motivation for this work is to elucidate the factors contributing to residual stress, deformation and fracture of oxide films so as to refine the microfabrication process for power MEMS manufacturing. The stress-temperature behavior of PECVD oxide films during annealing was studied. Analyses of residual stress relaxation, intrinsic stress generation, and the large deformation response of wafers were carried out. Preliminary experimental observations and estimates of oxide fracture were also provided.