Room temperature operating infrared (8-12 /spl mu/m) photodetector with InAs quantum dots in modulation doped heterostructures

A self-organized InAs quantum dot (QD) infrared photodetector operating at room temperature is demonstrated for the first time. 5 stacks of QD layers are embedded underneath 2-D channel of conventional HEMT structure. This device is designed to have the 2-D channel fully depleted to have small dark current. The spectral response has a peak at the wavelength of 10.6 /spl mu/m with D*=6/spl times/10/sup 10/ cm Hz/sup 1/2//W at 300 K and at the wavelength of 10.4 /spl mu/m with D*=3/spl times/10/sup 7/ cm Hz/sup 1/2//W at T=80 K. The very high detectivity and the room temperature operation are mainly due to low noise and extremely small dark current characteristic of fully depleted 2-D channel in which photocarriers are laterally transported.