Room temperature far infrared (8/spl sim/10 μm) photodetectors using self-assembled InAs quantum dots with high detectivity

Room temperature operation of far-infrared detectors made of self-assembled quantum dots embedded in the channel region of modulation-doped heterostructures is demonstrated. At room temperature, the detector shows a low dark current ranging in the nano-amperes at a bias voltage of 10 V. After the optimization of the separation between the quantum dot region and the 2DEG, a peak responsivity of 5.3 A/W is obtained at 9.0 μm. The high detectivities of 6×10/sup 8/ and 5×10/sup 10/ cmHz12//W are obtained at room temperature and 80 K, respectively.