The properties of N-doped and H-annealed Czochralski-grown Si wafers were investigated. The quality of the sub-surface was investigated by monitoring the generation lifetime of minority carriers, as measured by the capacitance-time measurements of a metal oxide Si capacitor. The intrinsic gettering ability was investigated by determining the Ni concentration on the surface and in the sub-surface as measured by graphite furnace atomic absorption spectrometry after the wafer was deliberately contaminated with Ni. From the results obtained, the generation lifetimes of these wafers were determined to be almost the same as, or a little longer than those of epitaxial wafers, and the intrinsic gettering ability was proportional to the total volume of O precipitates (bulk micro defects), which was influenced by the O and N concentrations in the wafers. Therefore, it was suggested that the sub-surface of the wafers was of good quality and the intrinsic gettering capacity was controllable by the N and O concentrations in the wafers.

Intrinsic Gettering in Nitrogen-Doped and Hydrogen-Annealed Czochralski-Grown Silicon Wafers. H.Goto, L.S.Pan, M.Tanaka, K.Kashima: Japanese Journal of Applied Physics - 1, 2001, 40[6A], 3944-6