Theory of the doped quantum well superlattice APD - A new solid-state photomultiplier

Using an ensemble Monte Carlo calculation, a new superlattice quantum well avalanche phododiode (APD) was analyzed. The device consisted of repeated unit cells formed from a p-i-n Al(0.45)Ga(0.55)As region followed by near-intrinsic GaAs and Al(0.45)Ga(0.55)As layers. The effects of various parameters, such as the high-field layer width, GaAs well width, low-field AlGaAs layer width, and applied electric field on the electron and hole ionization coefficients was studied. It was found that this device more nearly mimics a photomultiplier than the quantum well APD and the staircase APD, when applied to the GaAs/AlGaAs material system.