Tri-layer nanoindentation for mechanical characterization of ultra-low-k dielectrics

Recently the mechanical properties of nano-porous ultra-low-k (ULK) dielectric thin films have been characterized by nanoindentation using a tri-layer sample configuration. Tetraethyl orthosilicate (TEOS) silica was coated on the fragile ULK thin film to protect it from direct contact with nanoindenter tip. In this paper, the finite element method (FEM) simulations are conducted to investigate the effect of TEOS thickness, and to propose rules to design the tri-layer sample.