We investigated the influence of crucible rotation on oxygen concentration in the melt using numerical analysis in the unidirectional solidification process for solar cells. The results showed that oxygen concentration in the melt using crucible rotation is higher than that without using crucible rotation. The reason is that the magnitude of decrease in the flux of oxygen evaporation from the top of the melt is larger than that of oxygen dissolution from the crucible wall to the melt in the case of high crucible rotation rate. (C) 2008 Elsevier B.V. All rights reserved.