GaN avalanche photodiodes

We report the electrical and optical characteristics of avalanche photodiod es fabricated in GaN grown by metalorganic chemical vapor deposition. The c urrent-voltage characteristics indicate a multiplication of > 25. Experimen t indicates and simulation verifies that the magnitude of the electric fiel d at the onset of avalanche gain is greater than or equal to 3 MV/cm. Small -area devices exhibit stable gain with no evidence of microplasmas. (C) 200 0 American Institute of Physics. [S0003-6951(00)01207-9].