Type-II superlattice photodetector on a compliant GaAs substrate

A type-II superlattice (SL) of InAs-InGaSb has been grown on a compliant Ga As substrate by molecular beam epitaxy. This SL was designed for photocondu ctive infrared (IR) detection in the long wavelength IR band. The spectral photoresponse of this SL shows a sharp onset at 76.9 meV and a correspondin g cutoff wavelength at 13.9 mu m. A sixfold increase in the peak photorespo nse was measured in comparison to the response from a similar SL on a stand ard GaSb substrate.