Adhesive and mechanical properties of Carbon nanotube filled thermoplastic polyimide films for microelectronics packaging

Abstract

In this study the mechanical and adhesive properties of Multi-walled Carbon Nanotubes (MWNTs) filled polyimide composite films (MWNT-PI) are investigated to determine their usefulness as thermo-conductive packaging materials in microelectronics. MWNTs were mixed in low wt% during synthesis at poly(amic acid) (PAA) stage. MWNT-PI films were characterized using DMTA and tensile testing to determine viscoelastic behavior and mechanical properties. Adhesive strength and adhesive energy of bonded samples were determined in accordance with ASTM D 1002 and ASTM D 3762 respectively. The fractured surfaces were examined by scanning electron microscope (SEM) to determine failure patterns. The results showed that viscoelastic behavior of MWNT-PI films changes from liquidlike to solid-like with increasing MWNT wt content. Elastic modulus and strength at break of the composite films were found to increase with increase in MWNTs wt 00. However, elongation at break and breaking energy of films and lap shear strength and adhesive energy of bonded samples were found to initially increase with increase in MWNTs wt 00, but then after a critical value decreases.