Isolated Electron Injection Detectors With High Gain and Record Low Dark Current at Telecom Wavelength

We report on recent performance breakthroughs in a novel short-wave infrared linear-mode electron-injection-based detector. Detectors consist of InP material system with a type-II band alignment and provide high internal avalanche-free amplification mechanism. Measurements on devices with 10-μm injector diameter and 30-μm absorber diameter show internal dark current density of about 0.1 nA/cm² at 160 K. Compared with our previous reported results, dark current is reduced by two orders of magnitude with no sign of surface leakage limitation down to the lowest measured temperature. Compared with the best-reported linear-mode avalanche photodetector, which is based on HgCdTe, the electron-injection detector shows over three orders of magnitude lower internal dark current density at all measured temperatures. Using a detailed simulation with experimentally measured parameters, dark count rate of 1 Hz at 90% photon detection efficiency at 210 K is anticipated. This is a significantly higher operating temperature compared with superconducting detectors with a similar performance.