Measurement of Interdiffusion in Al-implanted GaAs-AlGaAs Quantum Wells Using Photoluminescence Spectroscopy

Ion implantation of quantum wells can enhance interdiffusion of the layers upon thermal annealing. From the measured shifts in photoluminescence peak wavelengths we have determined the band gap profile and thus the Ga-Al interdiffusion lengths of quantum wells with implanted Al doses ranging up to 3311x10 15cm-2 (1x10 19 cm- 3). When implantation is done through a patterned mask, a controlled variation of the band gap in the plane of the quantum well may be produced. We have used the interdiffusion results to fabricate arrays of two-dimensional and three-dimensional wells, of 400nm periodicity by implanting through a patterned mask produced by electron beam lithography.