An investigation of minority-carrier trapping centers in p-type Czochralski Si was performed by using the quasi-steady-state photo-conductance method. Wafers of B and Ga-doped Czochralski Si, with various resistivities and O contamination levels, were examined. A clear correlation of the trap density with the interstitial O concentration as well as with the B and the Ga concentration was detected. The experimental data suggested that O was a direct component of the defect complex responsible for the trapping, while the role of B and Ga was not fully resolved. The energy level and the trapping/de-trapping time constant ratio of the O-related trapping center were determined by using a simple single-level trapping model.

Oxygen-Related Minority-Carrier Trapping Centers in p-Type Czochralski Silicon. J.Schmidt, K.Bothe, R.Hezel: Applied Physics Letters, 2002, 80[23], 4395-7