High-responsivity submicron metal-semiconductor-metal ultraviolet detectors

Metal-semiconductor-metal ultraviolet (UV) detectors with finger width and pitch ranging from 0.5 to 4 mum have been fabricated on GaN. A superlinear enhancement of responsivity is observed when scaling down, in agreement with a model that includes optical absorption and the variation of the space-charge regions with bias. No degradation is found in terms of UV/visible contrast or photocurrent linearity. (C) 2002 American Institute of Physics.