Growth and x-ray characterization of strain compensated GaAs/AlAs distributed Bragg reflectors

We have grown strain compensated GaAs/AlAs distributed Bragg reflectors by solid source molecular beam epitaxy using carbon doping densities up to about 2 X 10(20) cm(-3), The residual strain with respect to the GaAs substrate can be as low as 1 X 10(-)4(.) This results in a large increase of their critical thickness with regard to the undoped case. We demonstrate that simulations of the x-ray diffraction patterns are essential in order to determine the chemical profile as well as the structural parameters of the GaAs:C and AlAs:C layers with high accuracy. The effective incorporation of carbon on lattice sites is in AlAs:C twice as large as in GaAs:C using the same incident carbon Bur. (C) 1996 American Institute of Physics.