InGaAs short wavelength infrared detector based on carrier collection effect

Based on collection effect of photogenerated carrier, the front-illuminated planar type InGaAs short-wave infrared (SWIR) detectors were fabricated by using N-InP/i-In0.53Ga0.47As/N-InP double-hetero structure materials. The series of detectors with the same dimension of 200μm×200μm contain several lateral collection regions and the width of each collection region is 15μm. The photoelectric characteristics of the photoresponse, I-V, spectral response and detectability of detectors with the lateral collection structure and normal structure were further analyzed. The build-in electrical field could effectively collect the electron/hole pairs generated in the lateral collection regions, so the photoresponse of lateral collection detector at 296 K is quite uniform by the laser beam induced current (LBIC) technology. Furthermore, the average peak detectivity and the density of dark current of the detectors with lateral collection structure reached 2.90× 1012 cm·Hz1/2/W and 3.94 nA/cm2 at -0.1 V respectively. It turns out that the lateral collection structure could effectively improve the dark current properties compared with the normal structure.