Cracking prediction of IC's passivation layer using J-integral

Abstract

Passivation layer cracks in ICs are often observed. The interfaces between compound or metal lines and passivation layers form typical corners, with two materials involved. The J-integral around the corner tip is presented as the passivation layer cracking criterion here, which is called modified J-integral criterion. With this modified J-integral criterion and the fracture toughness of passivation material, the passivation layer cracking can be predicted. Finite Element Method(FEM) is employed in this paper to calculate the J-integral by means of energy release rate. And the passivation corner J-integral value and most possible cracking direction are predicted for a given example.