Deep impurity levels and Ti solubilities were determined by means of deep-level transient spectroscopy. It was found that the Ti formed multi-levels; with an acceptor level of Ec - 0.09eV, a donor level of Ec - 0.27eV, and a double-donor level of Ev + 0.28eV. The solubilities, as a function of reciprocal temperature, were well-represented by straight lines with an associated activation energy of 3.8eV. The deep-level transient spectroscopy data indicated that the diffusivity (table 115) could be described by:

D(cm2/s) = 1.2 x 10-1exp[-2.05(eV)/kT]

Solubility and Diffusion Coefficient of Electrically Active Titanium in Silicon. S.Kuge, H.Nakashima: Japanese Journal of Applied Physics, 1991, 30[11A], 2659-63