Samples were implanted with 120keV S+ ions to doses of between 3 x 1013 and 1015/cm2. They were capped with an 80nm-thick film of amorphous hydrogenated Si, into which As was doped to a concentration of 2 x 1020/cm3. The samples were then annealed in Ar gas (850 to 1000C, 0.25h). It was found that the diffusivity of S (table 1) could be described by the expression:

D = Dm[KQ2/(1+KQ2)]

where K was a constant, Q was the implantation dose, and Dm was the diffusivity of a mobile complex.

M.Sakaguchi, K.Yokota, A.Shiomi, K.Hirai, H.Takano, M.Kumagai: Japanese Journal of Applied Physics, 1996, 35[1-8], 4203-8

Memorandum: S in GaAs

1000-1200C, D(cm2/s) = 4 x 103 exp[-4.04(eV)/kT] (Physical Review, 1961, 121, 1305); 900-1100C, D(cm2/s) = 2.6 x 10-5 exp[-1.86(eV)/kT] (Journal of the Electrochemical Society, 1965, 112, 697);  700-1000C, D(cm2/s) = 1.6 x 10-5 exp[-1.63(eV)/kT] (Semiconductors and Semimetals, Volume 4, Academic Press, 1968, 4)

Table 1

Diffusion Parameters for Implanted S in GaAs