The diffusion behavior of host and other atoms in plasma-enhanced chemical vapor deposited layers was studied. It was found that the group-III elements like Ga diffused very quickly at annealing temperatures of between 400 and 600C. The mobilization of these species by OH groups was proposed. The InGaAs host atoms could be detected, at concentrations of up to about 1018/cm3, in secondary-ion mass spectroscopic studies of

SiO2 films after annealing. Their effective diffusion coefficients were estimated to be between 10-15 and 10-13cm2/s within the temperature range which was investigated. Activation energies of about 0.3eV were derived for Ga. The out-diffusion of Ga was associated with the occurrence of 2 new peaks in the photoluminescence spectra of the InGaAs layers. A binding energy of about 018eV was deduced.

P.Ambrée, K.Wandel: Journal of Applied Physics, 1994, 76[2], 880-6

Figure 28

Diffusivity of Fe in SiO2

(a: separation-by-implantation type, b: bonded and etched-back type)