High detectivity short-wavelength II-VI quantum cascade detector

Abstract

We report on the experimental demonstration of a ZnCdSe/ZnCdMgSe-based short-wavelength photovoltaic Quantum Cascade Detector (QCD). The QCD operates in two spectral bands centered around 2.6 μm and 3.6 μm. Calibrated blackbody measurements yield a peak responsivity of 0.1 mA/W or 2400 V/W at 80 K, and a corresponding 300 K background radiation limited infrared performance detectivity (BLIP) of ∼2.5 × 1010 cm √Hz/W. Comparison of background illuminated and dark current-voltage measurements demonstrates a BLIP temperature of 200 K. The device differential resistance-area product, decreases from about 106 Ω cm2 at 80 K to about 8000 Ω cm2 at 300 K, indicative of the ultra-low Johnson noise in the detectors.

Effect of lattice disorder on the thermal conductivity of ZnBeSe, ZnMgSe and ZnBeMgSe crystals

“…IIeVI mixed crystals are still interested materials in modern electronics, optics and spintronics, primarily due to possibility of tuning material properties like energy gap or lattice constant. In general, following topics are now intensively studied: solar cells [1], infrared, ultraviolet, X-and g-ray photodetectors [2e4], magnetic materials [5], ZnO based devices [6] and light-emitting structures [7].…”

Characteristics of II–VI Quantum Dot Infrared Photo-Detectors

“…QDIPs were usually fabricated using self-assembled QDs made from III-V based material systems. Instead, in the last few years, II-VI ZnSe based material systems have been comprehensively studied for their possible use in infrared detection [6][7][8].…”

Growth and properties of wide bandgap (MgSe)n(ZnxCd1−xSe)m short-period superlattices

“…Additionally, quantum well infrared photodetectors (QWIPs) with performance comparable to those made with III–V materials [11] have been reported. Indeed, II–VI based quantum cascade detectors (QCDs [12]) and broadband QCDs [13] perform as well as any reported QCDs in III–V materials. However, devices from these materials are limited at shorter wavelengths by the quality of a Zn x Cd y Mg 1–x–y Se component as we go to the wider bandgaps (2.9–3.2 eV), and bandgaps higher than 3.2 eV are not usually achieved in sufficiently good quality.…”