LATERAL PATTERNING OF QUANTUM WELL STRUCTURES THROUGH COMPOSITIONAL MIXING. .

Impurity and crystal defect induced compositional disordering of GaAs/Al//xGa//1// minus //xAs layered structures offers new microfabrication possibilities. By ion implantation one can control the location of the mixed region and control the degree of mixing. Specimens in this study were implanted with aluminum or silicon at energies and doses to give similar implanted-ion profiles. These were examined by cross-sectional transmission electron microscopy, secondary ion mass spectroscopy, and cathodoluminescence. The samples implanted with Al were found to partially disorder at a depth centered around the maximum damage peak. Silicon was found to disorder the material more completely than Al, and the disordered region extended to a depth greater than two times the projectile range. The effects of different annealing conditions on the disordering are discussed. We also implanted samples through high resolution ion masks and studied the disorder profile by TEM. The study revealed that the lateral disorder front follows that expected from the straggle of implanted ions.