Study Of Ohmic Contact And UV-detector Based On GaN/Si

This work was supported by Talents Across the Century of the Ministry of Education of China and National Natural Science Foundation of China under Grant No. 69890230. The title of this project is "Growth of GaN on substrate silicon and its applications".In recent years, Gallium Nitride as a wide band gap semiconductor has attracted more and more attention and advanced rapidly, mainly due to its promising applications in short-wave light-emitting devices, photodetectors, as well as anti-radiation, high frequency and high power electronic devices. Up to date, it is still very hard to grow GaN bulk crystals, so the heteroepitaxial growth of high quality GaN thin films is the premise for the development of GaN-based devices. At the same time, the rapid progress on devices requires better ohmic contact between metals and GaN, so much more research work must be carried out at once.In this paper, we first presented a comprehensive review of the research history and current status of GaN material preparation and characterizations. On the basis of our renovated HWBE system, we conducted a detailed study of GaN epitaxy. In addition, the primary investigation of this paper is the ohmic contact between metals and GaN, and we made photodetectors based on GaN/Si.The main work include three contents as following:1. For the first time, we reported wurtzite single crystalline GaN on Si (111) substratesusing polycrystalline GaN as a buffer layer in a very simple reactive evaporation technique by HWBE.2. We researched the situation of ohmic contact between Al electrode, Ti/Al electrode and n-GaN with different annealing conditions. By using XRD and SIMS analytic methods, we put up a new concept about electrode annealing.3. We made photodetectors based on GaN/Si...