Electrical properties of silica-polyimide composite dielectric thin films prepared via sol-gel reaction and thermal imidization

Abstract

Thin dielectric films composed of silica and polyimide were prepared from tetraethoxysilane (TEOS) and precursor of poly(p-phenylene biphenyltetracarboximide)(BPDA-PDA). Silica particles were generated from TEOS via sol-gel process. BPDA-PDA polyimide was prepared from its flexible and soluble precursors, poly(p-phenylene biphenyltetracarboxamic acid)(BPDA-PDA PAA), and poly(p-phenylene biphenyltetracarboxamic diethyl ester)(BPDA-PDA ES), through thermal imidization process. In the present work, the electrical properties of the silica-polyimide hybrid composite films were examined utilizing a capacitance measurement by a high resolution electrometer/function generator system. The effects of TEOS contents and precursor types for polyimide matrix of the composites on the relative dielectric constant, dielectric dissipation factor, and resistivity of the composite films were investigated.