  A novel approach to the fabrication of GaNxAs1-x quantum dots and wires via
ion beam patterning is presented. Photomodulated reflectance spectra confirm
that N can be released from the As sublattice of an MBE-grown GaNxAs1-x film by
amorphization through ion implantation followed by regrowth upon rapid thermal
annealing (RTA). Amorphization may be achieved with a focused ion beam (FIB),
which is used to implant Ga ions in patterned lines such that annealing
produces GaAs regions within a GaNxAs1-x film. The profiles of these amorphized
lines are dependent upon the dose implanted, and the film reaches a damage
threshold during RTA due to excess Ga. By altering the FIB implantation
pattern, quantum dots or wires may be fabricated.
