Gallium self-diffusion in was measured directly in isotopically controlled GaP heterostructures. Secondary ion mass spectroscopy was used to monitor the intermixing of 69Ga and 71Ga between isotopically pure GaP epilayers which were grown by molecular beam epitaxy onto GaP substrates. The Ga self-diffusion in undoped GaP was described by:

D(cm2/s) = 2.0 exp[-4.5(eV)/kT

between 1000 and 1190C under P-rich conditions. The self-diffusion entropy was ∼4k.

L.Wang, J.A.Wolk, L.Hsu, E.E.Haller, J.W.Erickson, M.Cardona, T.Ruf, J.P.Silveira, F.Briones: Applied Physics Letters, 1997, 70[14], 1831-3