Demonstration of a Dual-Band Mid-Wavelength HgCdTe Detector Operating at Room Temperature

Abstract

In this paper, the performance of sequential dual-band mid-wavelength N+-n-p-p-P+-p-p-n-n+ back-to-back HgCdTe photodiode grown by metal-organic chemical vapor deposition (MOCVD) operating at room temperature is presented. The details of the MOCVD growth procedure are given. The influence of p-type separating-barrier layer on dark current, photocurrent and response time was analyzed. Detectivity without immersion D* higher than 1 × 108 cmHz1/2/W was estimated for λPeak = 3.2 μm and 4.2 μm, respectively. A response time of τs ∼ 1 ns could be reached in both MW1 and MW2 ranges for the optimal P+ barrier Cd composition at the range 0.38–0.42, and extra series resistance related to the processing RSeries equal to 500 Ω.