Enhancement of Electron-injection Detector Performance by their Unique Three-Dimensional Geometry

摘要

Electron-injection detectors are designed based on a new photon sensing mechanism. Here we demonstrate significant improvements in the device performance as a result of scaling the injector diameter with respect to the trapping/absorbing layer diameter. Devices with an order of magnitude smaller injector area with respect to the trapping/absorbing layer areas show more than an order of magnitude lower dark current, as well as an order of magnitude higher optical gain compared with devices of same size injector and trapping/absorbing layer areas. Devices with 10 μm injector diameter and 30 μm trapping/absorbing layer diameter show an optical gain of ～ 2000 at bias voltage of -3V with a cutoff wavelength of 1700 nm. We also derive analytical expressions for the electron-injection detector optical gain to qualitatively explain the significance of scaling the injector with respect to the absorber.