A new method was proposed for the estimation of interdiffusion coefficients in superlattices. This was based upon measurements of the thickness of layers which remained, without forming an alloy, after an annealing process which caused interdiffusion. The measurements were based upon the frequency of phonons from the Raman spectra. The interdiffusion coefficient values which were found in this way were almost the same as those previously published. It was noted that Ga atoms in the present superlattices diffused more rapidly into AlAs layers than Al atoms diffused into GaAs layers. The interdiffusion coefficients first decreased with annealing time and increased slightly when annealing was performed for more than 1.5h at 860C.

N.Hara, T.Katoda: Journal of Applied Physics, 1991, 69[4], 2112-6