Abstract
The understanding of the generation-annihilation phenomena of oxygen-related thermal donors (TDs) in p-type Czochralski silicon is of great importance for device fabrication and operation in microelectronic and photovoltaic industry. In this work, we report on oxygen clustering-based activation and partial annihilation of TDs in Cz-Si submitted to thermal annealing under nitrogen at 450 degrees C-800 degrees C for different thermal plateau exceeding 4 hours. The effect of thermal annealing on interstitial oxygen and dimer (O-i and O-2i) vibration modes appearing in the 580 cm(-1)-500 cm(-1) spectral range is studied. We found that heat treatment at 450 degrees C and 650 degrees C give rise to new thermal donors (NDs) that are located at 540 cm-1 and 532 cm-1, respectively. Subsequent to heat treatment above 650 degrees C, we depict the formation of new thermal oxygen defects having an IR signature in the 1800 cm(-1)-1500 cm(-1) spectral range, and which are especially sensitive to the thermal treatment duration. Resistivity measurements confirm that several of them are electrically active. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim