InGaAs/InP SAGM avalanche photodiodes incorporating a pseudoquaternary superlattice graded heterojunction grown by atmospheric-pressure MOCVD

We have demonstrated a high-speed GaInAs/InP SAGM avalanche photodiode grown by atmospheric-pressure MOCVD which incorporates a graded-bandgap GaInAs/InP superlattice layer to overcome hole pile-up effects inherent in the basic SAM devices. This approach offers considerable interface design flexibility without recourse to GaInAsP quaternary compositions. High-speed operation has been demonstrated without compromising the dark current or gain by the inclusion of the multiple heterojunctions of the superlattice.