Samples were diffused with Zn, via a 200 to 300nm protective ZrO2 layer. The diffusion depth exhibited a square-root time dependence. The absolute diffusivity values depended slightly upon the diffusion conditions (table 29). The layer had essentially no effect upon the carrier concentration profile or the activation energy.

J.E.Bisberg, A.K.Chin, F.P.Dabkowski: Journal of Applied Physics, 1990, 67[3], 1347-51