The epitaxial lateral overgrowth (ELO) process of depositing single crystal silicon over a mask is described. A CVD technique has been developed which consists of depositing silicon in openings in a mask and then growing the silicon laterally over the film. By optimizing the concentration in the gas, growth temperature, and the use of a growth procedure based on a series of growth/etch steps the nucleation of polysilicon over has been eliminated and monocrystalline ELO films have been grown. Low defect density ELO films have been achieved by orientating the oxide islands along the [010] direction on (100) substrates. The growth kinetics, overgrowth morphology, and defect formation in ELO films are described as a function of the growth conditions. One can conclude that optimization of the growth process has allowed us to grow monocrystalline, low defect density ELO films with smooth mirrorlike surfaces.