Deep-level defects in semi-insulating liquid-encapsulated Czochralski-type substrate materials were studied by using the thermally stimulated current technique. On the basis of the results, the behavior of defects as a function of heat treatment could be clarified for the first time. It was found that changes in the resistivity were closely related to changes in the thermally stimulated current signal intensities of T3 (0.31eV), T6 (0.58eV) and Tx (0.29eV). The net concentrations of these defects were found to have changed by 4 x 1014/cm3, after heat treatment at 800C, thus leading to a 3-fold increase in the resistivity.

H.Yoshida, M.Kiyama, T.Takebe, K.Fujita, S.Akai: Japanese Journal of Applied Physics, 1997, 36[1-1A], 19-22