Interband Quantum Cascade Infrared Photodetectors: Current Status and Future Trends

One of the critical limitations of photonic infrared (IR) photodetectors is the cooling requirement that is placed on it. Uncooled detectors are usually based on thermal detectors. Currently, microbolometer thermal detectors are produced in a larger volume than those of all other IR array technologies together. In recent years, their cost has drastically dropped (about 15% per year). Although their performance is modest, thermal detectors suffer from slow responses and they are not useful in multispectral detection. The (Hg, Cd)Te ternary system dominates photonic IR detector technology. It also has a superior performance under high operating temperature (HOT) conditions. At present, technological efforts are directed towards advanced heterojunction photovoltaic (Hg, Cd)Te detectors. In the last decade, several concepts have been proposed to improve the HOT photon detector's performance to include various kinds of materials, such as type-II AIIIBV superlattices (T2SLs), two-dimensional materials, and colloidal quantum dots. Among them, the most promising are interband quantum cascade photodetectors (IB QCPs) based on AIIIBV T2SLs considered in this paper. This paper reviews the history, present status, and possible future developments of IB QCPs for IR HOT applications. To date, the Rule 07 metric has been used as a proper approach for the prediction of the photodiode performance of p-on -n (Hg, Cd)Te and as a reference benchmark for alternative technologies. However, recently, it has been shown [Lee et al., Proc. SPIE 11407, 114070X (2020)] that uncooled depletion-limited (Hg, Cd)Te photodiodes exhibit further performance enhancement called Law 19, which is background-limited detectivity in the long-wavelength infrared spectral range. In this context, here, the performance of IB QCPs is compared with Law 19.

Automated summary

One critical limitation of photonic infrared photodetectors is the need for cooling. Currently, thermal detectors dominate the market due to their lower cost and superior performance under high operating temperature conditions. Efforts are being made to improve the performance of thermal detectors, with interband quantum cascade photodetectors based on AIIIBV T2SLs showing promise. Recent research has also shown that uncooled depletion-limited (Hg, Cd)Te photodiodes can exhibit enhanced performance called Law 19 in the long-wavelength infrared spectral range.