Low noise telcommunications APDs

Avalanche Photodiodes (APDs) are key components in modern lightwave communications systems. When compared to p-i-n diodes, APDs provide internal gain via impact ionization which leads to higher sensitivity. In addition, with proper device design, high gain bandwidth products can also be achieved. In this paper, we describe our work in making high speed, low noise APDs - operating at 1300 - using GaAs based multiplication regions. Our results to date have lead to a resonant cavity enhanced (RCE) APD, operating at 1310 nm, with an external quantum efficiency of 36% and an effective k factor of 0.1.