Advances in technology demand high volume production of semiconductors. Chemical vapor deposition (CVD) is a standard technique for producing semiconductors when quality and cost matter the most. The substrate geometry has a large effect on the deposition rate, which in turn plays a critical role in assessing the performance of the CVD reactor. Unfortunately, in the open literature, not much attention has been paid to the substrate geometry. Instead, standard geometries and those produced via heuristics have been employed. This paper proposes a deposition model with a flexible substrate geometry. Using this model, the effect of various substrate geometries on the deposition rate of zinc sulfide is assessed. The results indicate that certain substrate geometries change the flow patterns, create recirculation, and increase the deposition rate. (c) 2007 Elsevier B.V. All rights reserved.