A study of HgCdTe HOT MW infrared detector

Abstract

In this paper, we report the mid-wavelength HgCdTe HOT (High Operating Temperature) detector with 640×512 array and center distance of 15μm by JueXin Microelectronics Co., Ltd. The detector can work steadily when the focal plane array temperature is 140K. We grew up the CdZnTe substrates by vertical Bridgman technique and HgCdTe materials by liquid phase epitaxy process, then the planar n+-on-p diodes were formed by boron ion implantation. Through the optimization of material growth and device fabrication process, the dark current of the device is reduced. At 140K, the cut-off wavelength of the device is 4.7μm, the dark current density reaches 3×10-7A/cm2, and the dark current density of the device is close to that of P-on-N (rule 07). At the focal plane operating temperature of 140K, the operability of the detector can reach more than 99.5%, the NETD is less than 13mK, and the RFPN is less than 0.6mV (close to temporal noise). At the same low temperature, when the operating temperature of the device changes from 80K to 140K, the power consumption of the detector module is reduced by 37% and the cooling time is shortened by 36%.