New Reworkable High Temperature Low Modulus (in Excess of 400–500 °C) Adhesives for MCM-D Assembly

Abstract

Large area substrate processing is a key solution for improving the productivity of multi-chip module deposition (MCM-D) technology. This project is focused on high temperature low modulus polymeric adhesives for attachment of silicon tiles to suitable pallets to facilitate large area film processing of MCM structures. Current high temperature polymeric materials are predominately polyimide-amide, siloxane modified polyimide-amide, Bisbenzocyclcobutene (BCB), and polynorbornene materials, all of them are neither reworkable nor flexible, which creates an obstacle to remove the coated substrates and to reuse the high cost pallets. However, one of the approaches to address this demand is introducing a low modulus elastic material combined with a unique thermal stabilizer, which will be thermally stable at 400°C for 1 h and thermally degradable at 450°C after 1 h. A series of novel reworkable high temperature (in excess of 400–450°C) adhesives have been developed in this study, that can meet the requirements of adhesion, viscosity, low modulus, thermal stability, and reworkability for MCM-D mass production. The mechanism of thermal stabilizer functionality and adhesive reworkability is presented in this study. In addition, finite element modeling is used to predict the out-of-plane warpage, axial, and interfacial stresses of the tiles-on-pallet palletized assemblies. [S1043-7398(00)00501-6]