β-Ga₂O₃ films grown on Al₂O₃ by a metalorganic chemical vapor deposition technique were used to fabricate a solar-blind photodetector with a planar photoconductor structure. The crystal structure and quality of the β-Ga₂O₃ films were analyzed using X-ray diffraction and micro-Raman spectroscopy. Si ions were introduced into the β-Ga₂O₃ thin films by ion implantation method and activated by an annealing process to form an Ohmic contact between the Ti/Au electrode and the β-Ga₂O₃ film. The electrical conductivity of the β-Ga₂O₃ films was greatly improved by the implantation and subsequent activation of the Si ions. The photoresponse properties of the photodetectors were investigated by analyzing the current–voltage characteristics and the time-dependent photoresponse curves. The fabricated solar-blind photodetectors exhibited photoresponse to 254 nm wavelength, and blindness to 365 nm light, with a high spectral selectivity.

A long‐standing goal of GaN device research has been the development of a reliable, well‐controlled process for p‐GaN formation by ion implantation. Results to date have indicated an activation of 1% or less using high‐temperature rapid thermal annealing (RTA) techniques and coimplantation. Although Mg is a relatively deep acceptor, this is still much less than the theoretically achievable value (8.2% based on the 160 meV acceptor level). A multicycle RTA process is presented that is capable of achieving up to 8% activation of the Mg‐implanted GaN. This approaches the theoretical value, and represents a significant step in GaN device research.