Aluminum Ion Implantation Enhanced Intermixing of GaAs-AlGaAs Quantum Well Structures.

We have studied aluminum implantation enhanced intermixing of GaAs-AlGaAs quantum well structures using low temperature photoluminescence. The energy shift of the electron-heavy hole exciton was determined for Al doses varying from 2x10 sup 13 cm sup(-2) to 1x10 sup 15 cm sup(-2) after either furnace annealing at 800C or optical rapid thermal annealing at 925C. A variational calculation yields the diffusion length from the energy shift of the exciton. This shift is due both to the increase of Al in the center of the well and to the change in electron and heavy hole confinement energies.