Preparation of Al-O-N films by electron cyclotron resonance plasma-assisted chemical vapor deposition

Al-O-N films were prepared by electron cyclotron resonance plasma-assisted chemical vapor deposition (ECR PACVD) using an AlBr3-N2O-N-2-Ar-H-2 gas system. The structure, composition, deposition rate and optical properties were, investigated. The compositions were controlled by changing die N2O/(N2O + N-2) dow rate ratio (R). The refractive index was varied from 1.60 to 2.10, and the cutoff photon energy at 10% transmittance (E-g/10) from 5.1 to 7.0 eV as the R changed from 0 to 1.0. The Al-O-N films were composed mainly of a mixture of Al2O3 and AlN. An aluminum oxynitride phase was also identified at R = 0.2 to 0.53. The Al-O-N films contained a (001)-oriented hexagonal AlN phase at R = 0.025. and the films were amorphous at R > 0.05.