New reworkable high temperature low modulus (in excess of 400-500 degrees C) adhesives for MCM-D assembly

Large area substrate processing is a key solution for improving the product ivity of multichip module deposition (MCM-D) technology. This project is fo cused 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 predom inately polyimide-amide, siloxane modified polyimide-amide, Bisbenzocyclcob utene (BCB), and polynorbornene materials, all of them are neither reworkab le nor flexible, which creates an obstacle to remove the coated substrates and to reuse the high cost pallets. However, one of the approaches to addre ss this demand is introducing a low modulus elastic material combined with a unique thermal stabilizer, which will be thermally stable at 400 degreesC for 1 h and thermally degradable at 450 degreesC after 1 h. A series of no vel reworkable high temperature (in excess of 400-450 degreesC) adhesives h ave been developed in this study, that can meet the requirements of adhesio n, viscosity, low modulus, thermal stability, and reworkability for MCM-D m ass production. The mechanism of thermal stabilizer functionality and adhes ive reworkability is presented in this study. In addition , finite element modeling is used to predict the out-of-plane warpage, axial, and interfacia l stresses of the tiles-on-pallet palletized assemblies. [S1043-7398(00)005 01-6].