Asymmetric AlGaAs/GaAs/InGaAs Based Quantum Well Long Wavelength Infrared Photodetector

An asymmetric quantum well structure has been developed for 6-10 μm detection. The asymmetric structure consists of N-doped InGaAs wells, GaAs steps and undoped AlGaAs barriers. Due to the strong coupling effect of the electronic state wave functions, significant absorption is observed. But, the absorption decreases with the increasing Indium concentration of In y Ga 1-y As. A reasonable responsivity of 83 mA/W is obtained from our considered model. Responsivity can be increased by manipulating structural parameters of the materials. Enhanced responsivity of 150 and 112 mA/W are observed for doping of 1x10 ¹⁸ cm ^-3 and Quantum wells of 26 respectively.