A visible-blind heterobipolar phototransistor, with low threading dislocation density, was prepared by means of organometallic vapour phase epitaxy and low-temperature interlayer techniques. The device performance at up to 200C was marked by an exponential evolution of the dark-current under the influence of a deep defect near to 0.459eV. Photo-induced transient spectroscopy, between 50 and 175C, also furnished evidence of defects at about 0.093, 0.137 and 0.205eV.

Photoresponse and Defect Levels of AlGaN/GaN Heterobipolar Phototransistor Grown on Low-Temperature AlN Interlayer. R.Mouillet, A.Hirano, M.Iwaya, T.Detchprohm, H.Amano, I.Akasaki: Japanese Journal of Applied Physics - 2, 2001, 40[5B], L498-501