AlInN-based ultraviolet photodiode grown by metal organic chemical vapor deposition

AlInN, one of the III-nitride semiconductors, is expected to find its application as transistors, sensors, light emitters of electronic, and optoelectronic devices. When the lattice alignment of AlInN is made similar to GaN, a great deal of crack-free AlInN film growth is possible on GaN layers. We have successfully grown AlInN and AlGaN films by metal organic chemical vapor deposition. The structural analysis for the metal organic chemical vapor deposition grown films show that they have the same structure and were used to produce AlInN and AlGaN-based ultraviolet (UV) photodiodes. This paper describes the growth and fabrication of AlGaN and AlInN-based UV photodiodes and analyzes their device performance. For an AlInN, the peak responsivity at zero bias was measured to be 140mA∕W at 230nm, corresponding to an external quantum efficiency of 74%. AlInN was found to be more suitable than AlGaN for UV photodiodes with a cutoff wavelength in the UV-C range.