Long wave infrared InAs-InGaAs quantum-dot infrared photodetector with high operating temperature over 170 K

Abstract

A long wave infrared InAs-InGaAs quantum-dot (QD) infrared photodetector (QDIP) with a peak detection wavelength of 9.9 µm and operating temperature of over 170 K is reported. Peak specific photodetectivity D* of 3.8 × 109 cm Hz1/2 W−1 and 1.3 × 108 cm Hz1/2 W−1 were obtained at the detector temperature T = 78 K and T = 170 K, respectively. A large photoresponsivity of 4.6 A W−1 and high photoconductive (PC) gain of > 144 were demonstrated at T = 170 K. The high temperature performance is attributable to the dark current reduction by the double Al0.2Ga0.8As barrier layers employed in the QDIP and the high PC gain at the elevated temperature. The performance demonstration indicates that the QDIP with double current-blocking barriers is promising for high-temperature long wave infrared photodetection.

Interband Photoconductivity of Metamorphic InAs/InGaAs Quantum Dots in the 1.3–1.55-μm Window

“…In(Ga)As QD photodetectors based on interband and intersubband transitions are currently actively investigated for enhanced detection from near-IR to longwave-IR ranges due to their response to the irradiation at normal incidence [ 26 – 30 ]. For instance, the intersubband transitions of electrons between quantum-confined levels and continuum states can be engineered by embedding InAs QDs in InGaAs layers [ 29 – 32 ], as this design allows to tune the detection peak wavelength, to control the response by an externally applied bias and to reduce the dark current [ 33 , 34 ]. To date, there are no papers about the implementation of metamorphic QD structures in photodetectors.…”

The conduction band absorption spectrum of interdiffused InGaAs/GaAs quantum dot infrared photodetectors

“…The E 1 0 state is strongly bound to the QD and therefore QDIPs do not usually register a photocurrent from this state. The f-sum rule implies that for the typical QD densities obtained by selfassembled growth (few 10 10 cm À2 ), the large responsivities (>1 A/W) reported for some QDIPs [28][29][30][31][32][33] is most certainly due to a larger photoelectric gain. For example, 10 QD layers with a sheet density of 5 Â 10 10 cm -2 per layer will have a peak absorption of at most approximately 0.76% for an absorption linewidth of 35 meV and a QD effective mass of 0.04 m e .…”

Photovoltaic and optoelectronic properties of InAs(100)-based photoconductive cells with quantum dots and nanopits

“…The newest in the competition for infrared photodetector is the normal incidence quantum-dot photodetectors (QDIPs) [1,[3][4][5]10] in semiconductors such as InGaAs/InP, InGaAs/GaAs, InGaAs/InAs, InSb/InAs and SiGe/Si. These and other QDs-based devices are expected to perform well at elevated temperatures due to their three-dimensional carrier confinement characteristics [11][12][13][14].…”