Dark current characterisation of HgCdTe infrared detectors

Dark current is the main factor affecting the performance of the HgCdTe detector, and this paper analyses the dark current according to the production mechanism of dark current. Temperature, bias voltage, wavelength and Cd composition all affect the size and composition of dark current. The higher the temperature, the larger the dark current, the diffusion current and the production-complex current dominate above the critical temperature point, and the tunnelling current dominates below the critical temperature; within the allowable deviation range, the high bias voltage shows a larger dark current due to the dominance of the tunnelling current; the longer the wavelength, the smaller the Eg becomes, and the larger the dark. The larger the Cd composition becomes, the larger the Eg becomes, and the direct tunnelling current become the dominance of dark current. By analysing the influence factors of dark current, it has some guiding significance to improve the development process of the detector, and to set up a new system of dark current of the detector, and to set the appropriate working temperature and bias voltage when the detector is used, so that the detector can work in the best performance.