Avalanche photodiode with sectional InGaAsP/InP charge layer

An InGaAs/InP avalanche photodiode (APD) with a sectional InGaAsP/InP charge layer at the heterointerface between the InGaAs absorption and InP multiplication region has been designed, fabricated and tested. We demonstrate a new APD structure that utilizes the sectional 140 nm thin charge layer and a 500 nm thin multiplication layer. The band diagram, electrical field distribution and current–voltage (I–V) characteristics up to punch-through voltage have been simulated. The fabricated mesa structure photodiode shows responsivity 0.9 A/W at 1310 nm at 20 V and avalanche gain up to 10 near breakdown voltage 36 V. The measured results revealed that the sectional charge layer could be used for control of the electric field profile in the APD structure.