Characterization and cure of dielectric and conducting polymer thick films

Abstract

Polymer thick films are screenable polymer pastes which vary from electrically non-conducting to electrically conducting. These materials typically contain significant amounts of high boiling solvents, and cure therefore involves removal of solvent in addition to crosslinking of the polymer matrix. In this study thermogravimetric analysis and dynamic mechanical analysis were utilized to characterize the residual solvent and glass transition behavior, respectively, with cure of the polymer thick films. Thickness was maintained constant at approximately 25μ and 100μ by using stainless steel mesh substrates. Results showed that IR curing, although able to heat more rapidly, did not accelerate the cure beyond that expected from time at temperature. Time-temperature superposition kinetics were employed to measure activation energy of cure, generate master cure curves, and to quantify IR cure time-temperature profiles. Cure models describing Tg and residual cure as a function of time, temperature, and film thickness were developed.