The transient ion drift in the depletion region of a Schottky barrier was used to determine ion diffusivities at moderate temperatures. A simple theoretical model, together with classical transient signal analysis, permitted the ion diffusion constant to be deduced. When the method was applied to the diffusion of Cu, data were obtained for 280 to 400K. These results agreed well with both low-temperature and high-temperature data and could be described by:
D (cm2/s) = 4.5 x 10-3 exp[-0.39(eV)/kT]
T.Heiser, A.Mesli: Applied Physics A, 1993, 57[4], 325-8
The best linear fits to the solute diffusion data ([124] to [129], [133] to [144], [146] to [176], [188] to [192], [196] to [211], [215] to [223], [234] to [242], [252] to [283], [292] to [298], [306] to [314]) yield:
Al: Ln[Do] = 0.45E – 32.8 (R2 = 0.81); As: Ln[Do] = 0.29E – 23.2 (R2 = 0.87);
Au: Ln[Do] = 0.16E – 12.4 (R2 = 0.16); B: Ln[Do] = 0.29E – 22.6 (R2 = 0.79);
Cu: Ln[Do] = 0.22E (R2 = 0.86); Fe: Ln[Do] = 0.62E – 15.8 (R2 = 0.53);
Ga: Ln[Do] = 0.20E - 16.9 (R2 = 0.78); Ge: Ln[Do] = 0.29E – 23.2.8 (R2 = 0.98);
H: Ln[Do] = 0.17E - 9.9 (R2 = 0.07); Li: Ln[Do] = 0.25E – 9.6 (R2 = 0.48);
Ni: Ln[Do] = 0.29E - 19.4 (R2 = 0.66); O: Ln[Do] = 0.34E – 21.6 (R2 = 0.95);
P: Ln[Do] = 0.35E - 27 (R2 = 0.94); Sb: Ln[Do] = 0.35E – 29.3 (R2 = 0.96);
Si: Ln[Do] = 0.33E - 29 (R2 = 0.86)