PHOTOCONDUCTOR GAIN MECHANISMS IN GAN ULTRAVIOLET DETECTORS

GaN photoconductive detectors have been fabricated on sapphire substra tes by metal organic vapor phase epitaxy and gas-source molecular beam epitaxy on Si (111) substrates. The photodetectors showed high photoc onductor gains, a very nonlinear response with illuminating power, and an intrinsic nonexponential photoconductance recovery process, A nove l photoconductor gain mechanism is proposed to explain such results, b ased on a modulation of the conductive volume of the layer. (C) 1997 A merican Institute of Physics.