Effect of Au nanoparticles on the optical and electrical properties of Nb-doped β-Ga2O3 film

The Nb-doped β-Ga2O3 (β-Ga2O3:Nb) thin films have been deposited on the p-Si and Au nanoparticles decorated p-Si substrates by radio frequency magnetron technique in argon ambient. All the annealed β-Ga2O3:Nb films are composed of similar crystallite sizes obtained by XRD and SEM measurements. The β-Ga2O3:Nb thin film grown on the Au nanoparticles decorated substrate shows lower transmittance and narrower band gap compared to that of grown on p-Si reference substrate. Photoluminescence intensity was quenched because of the short separation distance between semiconductor and the Au nanoparticles. The current density was enhanced and the barrier height of the β-Ga2O3:Nb/p-Si heterojunction was reduced by inserting Au nanoparticles in the interface of β-Ga2O3:Nb/p-Si heterojunction.