Properties of Metal / Polyphenylquinoxaline Interfaces

Abstract

ABSTRACTWe have investigated the microscopic properties of copper and chromium layers deposited on polyphenylquinoxaline (PPQ). PPQ is a thermostable polymer used for multichip module applications. The metal is deposited under ultra-high vacuum conditions and analysed in-situ by X-ray photoemission (XPS) and atomic force microscopy (ex situ). Copper does not react significantly with the PPQ and tends to diffuse into the polymer matrix upon annealing. On the contrary, chromium strongly reacts with the polymer surface at room temperature. With increasing metal coverage, chromium grows in a layer-by-layer mode and the reacted interface is progressively burried under the pure metal layer.