The lattice strain caused by O diffusion was proportional to the O content, and the expansion coefficient of O in Si was 4.5 x 10-24. The O diffusion coefficient was estimated from the strain distribution in the O-diffused layer of samples annealed in a humid atmosphere, and was described by:

D(cm2/s) = 9.1 x 10-2exp[-2.4(eV)/kT]

The diffusion coefficient in (100) wafers was larger than that in (111) wafers.

Y.Takano, M.Maki: 2nd International Symposium on Silicon Materials Science and Technology, 1973, 469-81