The effect of film edge shapes on the stress field for a multilayered semiconductor structure: A finite-element analysis study

Resolved shear stress distributions, arising from thermal stresses induced by temperature variations, are calculated near the corners of the discontinuities of SiO₂ film deposited over a GaAs substrate and covered with an overlay of InGaAs. The resolved shear stress distributions are then used to determine the location and extent of the area, where dislocations are expected to occur by comparison to the critical-resolved shear stress value of the material. The implications on the stress distribution of a modification in the original shape of the film edge are illustrated and discussed as a possibility to reduce dislocation occurrence.