We have investigated Czochralski grown low boron doped silicon wafers after oxygen precipitation using high temperature preannealing. Wafers originating from the part of the silicon ingot close to head and close to tail were used for the experiments representing different temperature history of the wafers. The loss of interstitial oxygen, precipitate morphology and stoichiometry at various stages of precipitation were determined by infrared absorption spectroscopy at liquid nitrogen and at room temperature. The impact of a high temperature preannealing at various temperatures on the parameters of precipitates including also their concentration determined from chemical etching was observed during the growth of oxygen precipitates. The obtained results were compared with transmission electron microscopy. (C) 2012 Elsevier B.V. All rights reserved.