ELECTRON-DIFFUSION LENGTH AND LIFETIME IN P-TYPE GAN

We report on electron beam induced current and current-voltage (I-V) m easurements on Schottky diodes on p-type doped GaN layers grown by met al organic chemical vapor deposition. A Schottky barrier height of 0.9 eV was measured for the Ti/Au Schottky contact from the I-V data. A m inority carrier diffusion length for electrons of (0.2 +/- 0.05) mu m was measured for the first time in GaN. This diffusion length correspo nds to an electron lifetime of approximately 0.1 ns. We attempted to c orrelate the measured electron diffusion length and lifetime with seve ral possible recombination mechanisms in GaN and establish connection with electronic and structural properties of GaN. (C) 1998 American In stitute of Physics. [S0003-6951(98)03848-0].