International Business Machines Corporation
Crack bifurcation in back-end-of-line

Abstract:

Embodiments of the present invention are directed to a new crack stop system and a method for providing an interlayer dielectric (ILD) crack bifurcation in semiconductor back-end-of-line (BEOL). In a non-limiting embodiment of the invention, a crack stop is formed over a substrate. The crack stop can span one or more dielectric layers. A topologically interlocking composite structure is formed adjacent to the crack stop and over the substrate. The topologically interlocking composite structure spans the one or more dielectric layers. A capping film is formed over the topologically interlocking composite structure and one or more metal interconnect layers are formed over the capping film. The composite structure includes a bulk matrix material and embedded inclusions. To promote crack bifurcation, materials of the inclusions and bulk matrix material are selected to ensure that the Young's modulus of the inclusions is greater than the Young's modulus of the bulk matrix material.