Low temperature growth of AlN films by microwave plasma chemical vapour deposition using an AlBr 3-H 2-N 2 gas system

Abstract

Polycrystalline AlN films were grown on Si(100) substrates by coaxial line-type microwave plasma chemical vapour deposition using an AlBr 3-H 2-N 2 gas system. The effects of substrate temperature and N 2:AlBr 3 gas flow ratio on the film structure, composition, crystallinity and deposition rate were investigated. Polycrystalline AlN films of fine-grained structure and excellent c axis orientation were grown at T sub = 520–560°C and at N 2:AlBr 3 gas flow ratios above 13. The film deposition rate under these conditions was 60 nm min -1. On the basis of an analysis of plasma emission spectra, the film formation process is also discussed.