Silicon hetero-interface photodetector

Abstract
We propose and demonstrate a novel avalanche photodetector that uses separate InGaAs absorption and Si multiplication regions fabricated by wafer fusion. Directly integrating InGaAs and silicon layers in an avalanche photodetector combines the high long-wavelength absorption capabilities of InGaAs and the avalanche multiplication properties of Si. The large ratio of electron and hole ionization coefficients of silicon results in lower noise and a higher gain bandwidth product than achievable using III-V semiconductors in avalanche regions.