Adhesion of Polyimides to Ceramic Substrates: Role of Acid-Base Interactions

Abstract

Adhesion of polyimides to ceramic substrates such as SiO2, Al2O3, and MgO, and interfacial interactions were studied using XPS, SEM, and the peel test. The peel strength of polyimides on SiO2 and Al2O3, is almost identical and higher than that on MgO at the same polyimide thickness. Contrary to the failure within the polyimides on SiO2 and Al2O3, Mg was found on the peeled PMDA-ODA acid-derived polyimide surface, implying weakening of MgO by interfacial reactions with polyamic acid. With the neutral polyamic ethyl ester, the locus of failure on MgO was changed to the apparent weak boundary layer of the ester-derived polyimide. On SiO2 and Al2O3, the peel crack propagated with a discontinuous stick-slip process. The constant interspacing between transverse stick-slip striations on the peeled polyimide surfaces has confirmed that plastic bending is the major energy dissipation process with a minimal contribution from tensile loading. © VSP 1990.