Low dark-current, high gain GaInAs/InP avalanche photodetectors

High performance inverted-mesa GaInAsP/InP avalanche photodiodes responding out to 1.25 μm have been fabricated. Uniform avalanche gains
M
, of 700 dark-current densities of
3 \times 10^{-6}
A/cm
²
at
M = 10
, and an excess noise factor of ∼3 at
M = 10
have been achieved by placing the p-n junction in the InP and using a new passivation technique. Pulse-response rise times of less than 160 ps, limited by the rise time of the mode-locked Nd:YAG laser pulse, were measured with an avalanche gain of 40.