2.4 lm cutoff wavelength avalanche photodiode on InP substrate

An InP-based avalanche photodiode with a cutoff wavelength of 2.4 mm is reported. Type-II GaInAs-GaAsSb quantum wells latticematched to InP were used in the absorption region of the photodiode for long-wavelength absorption. The device exhibited multiplication gain in excess of 30 at room temperature and in excess of 200 at 225 Kelvin with dark current density near breakdown of less than 0.66 mA=cm.