High-Speed InP/InGaAsP/InGaAs Avalanche Photodiodes Grown by Chemical Beam Epitaxy.

We report high-performance InP/InGaAsP/InGaAs avalanche photodiodes (APDs) grown by chemical beam epitaxy. These APDs exhibit low dark current ( 50 nA at 90% of breakdown), good external quantum efficiency (> 90% at lambda = 1.3micron), and high avalanche gain (M sub o ~ 40). In the low-gain regime bandwidths as high as 8 GHz have been achieved. At higher gains a gain- bandwidth-limited response is observed; the gain-bandwidth product is 70 GHz.