Development of high-performance III-nitride-based semiconductor devices

In the past decade, research work in AlGaInN wide band gap semiconductors h as continuously intensified, mainly because of their exceptional expected m aterial properties which make them the ideal materials for numerous devices , including solar blind ultraviolet photodetectors. In this paper, the grow th and characterization of AlGaInN thin films on sapphire and silicon subst rates by metalorganic chemical vapor deposition is presented. The fabricati on and testing results of GaN and AlxGa1-xN based ultraviolet photodetector s are discussed, including high speed low noise GaN based Schottky metal-se miconductor-metal photodetectors with high ratio of rejection of visible li ght to UV light, high visible blindness GaN p-i-n photodiodes, AlxGa1-xN ph otoconductors in the entire Al compositional range, and the first AlxGa1-xN p-i-n photodiodes (0 less than or equal to x less than or equal to 0.15) e ver reported. Finally, in an on-going effort to improve the quality of AlGa InN materials, the LEO growth and characterization of low defect density Ga N films on both (00.1) sapphire and (111) silicon substrates is described.