Enhancement of AlN Crystallisation for Thin Film Leakage Current Minimisation

Abstract

Aluminium nitride (AIN) is a promising thin film insulation material layer in electronic devices. Magnetron sputtering method is usually employed to sputter-deposit AlN on silicon (Si) using pure aluminium metallic target and low base pressure vacuum condition. We manage to sputter highly crystalline AlN〈100〉 and AlN〈002〉 from AlN ceramic target on Si〈100〉 substrate in a relatively high chamber’s base pressure at 200 W - 250 W of sputtering power. We found that 250 W of sputtering power increases the AlN grain size, thin film thickness and assists the growth of AlN〈002〉 that eventually suppresses the leakage current density of AlN thin film layer to 46.33 pA/cm2. High degree of AlN〈002〉 crystallisation may propose good electrical insulating properties in AlN thin film layer, to be used in electronic devices that require low leakage current.

Keywords: crystal growth, crystal structure, Electrical properties, Microstructure, thin films