Ga N ∕ Al Ga N ultraviolet/infrared dual-band detector

Abstract

Group III-V wide band gap materials are widely used in developing solar blind, radiation-hard, high speed optoelectronic devices. A device detecting both ultraviolet ͑UV͒ and infrared ͑IR͒ simultaneously will be an important tool in fire fighting and for military and other applications. Here a heterojunction UV/IR dual-band detector, where the UV/IR detection is due to interband/intraband transitions in the Al 0.026 Ga 0.974 N barrier and GaN emitter, respectively, is reported. The UV threshold observed at 360 nm corresponds to the band gap of the Al 0.026 Ga 0.974 N barrier, and the IR response obtained in the range of 8-14 m is in good agreement with the free carrier absorption model.

Performance improvements of ultraviolet/infrared dual-band detectors

“…On the other hand, the Si impurity-related transition can lead to an increased dark current for a detector designed to operate in a shorter wavelength region. A similar response was also reported for the previous GaN/Al 0.026 Ga 0.974 N HEIWIP detector [21].…”

“…In comparison with UV detectors, the reported GaN/ AlGaN HEIWIP UV/IR dual-band detectors (previous [21] and current) have much lower UV responses. The probable cause for the low UV response is the high absorption of UV radiation within the 0.2 lm thick top-contact layer.…”

“…The oscillations in the response spectrum can be fitted with Fabri-Perot interference in the structure. The experimental and calculated thresholds of the detector reported in this article and a similar GaN/Al 0.026 Ga 0.974 N detector reported previously [21] in both UV and IR regions is shown in Fig. 6.…”

Monolithically integrated UV/IR‐photodetectors based on an AlN/GaN‐based superlattice grown on an AlGaN buffer layer

“…which should be used for any reference to this work onstrations include solutions based on AlGaN/GaN [3], Si/p-Si [4], and GaAs/p-GaAs layer stacks [5] using interband absorption for the shorter detection wavelength and free-carrier absorption for the longer wavelength. In addition, multi-color detectors based on bias voltage switching and using excited states in either quantum dots or minibands have been proposed and characterized [6][7][8].…”

Dual band HEIWIP detectors with nitride materials

“…Dual band detectors operating in the NIR and MIR/far-infrared (FIR) regions [9][10][11] based on the group III-As material system have been reported. Previously a detector responding in both the UV and MIR ranges was reported, 12 however, the detector needed separate modulation to distinguish UV and IR radiation. Here results are reported on a detector capable of operating in both the UV and 8-14 µm IR spectral ranges simultaneously without separately modulating the incident radiation, thus eliminating the difficulties of assembling several detectors when multiband detection is required.…”