A photon detector with very high gain at low bias and at room temperature

Abstract

We report on a photon detector aimed at low light detection, which is based on the combination of small sensing volumes and large absorbing regions. Fabricated devices show stable gain values in the range of 1000–10 000 at bias voltages of ∼1V at 1.55μm at room temperature. Submicron devices show dark current less than 90nA and unity gain dark current density values less than 900nA∕cm2. The noise equivalent power (NEP) is measured to be 4fW∕Hz0.5 at room temperature without any gating, which is similar to NEP of current InGaAs∕InP avalanche photodetectors in gated operation.