Crystals which were dislocation-free were grown by using the Czochralski method, but without using the Dash-necking process. It was found that the B-limit, on the seed concentration for zero dislocation formation due to thermal shock, was 1018/cm3 and that the maximum allowable discrepancy in B concentration between seed and crystal was 7 x 1018/cm3 for zero dislocation formation due to lattice misfit. On the basis of these results, a dislocation-free seed with an (001) orientation and a B concentration of 3 x 1018/cm3 was used to grow a crystal from an undoped melt. The B concentration in the grown crystal was only about 7.5 x 1014/cm3. No dislocations were generated in the seed by thermal shock during dipping, and no dislocations formed in the grown crystal; even though there was a slight lattice misfit between the seed and the grown crystal.

Dislocation-Free Czochralski Si Crystal Growth without the Dash-Necking Process - Growth from Undoped Si Melt T.Taishi, X.Huang, T.Fukami, K.Hoshikawa: Japanese Journal of Applied Physics - 2, 2000, 39[3A/B], L191-4. See also: Journal of Crystal Growth, 2000, 213[3-4], 283-7