Resistance of through-thickness grain boundaries to cleavage cracking in silicon thin films

Abstract

Through a set of microtensile experiments, it was discovered that the resistance of a free-standing polycrystalline silicon thin film to cleavage cracking is not a material constant. Rather, it is highly dependent on the film thickness. As the film thickness changes from 1 to 10 μm, the fracture resistance increases by 20–60%, which can be attributed to the nonuniform nature of the crack front advance across grain boundaries.