Vertical diffusion furnace and cap therefor

摘要

A vertical diffusion furnace and a cap therefor are provided to minimize diffusion non-uniformity in a diffusion furnace caused by the positioning of a reaction gas outlet. In the vertical diffusion furnace, a reaction gas outlet is formed in the lower portion of a cap and adapted to extend downward through a flange. Thus, is provided a means to maintain diffusion uniformity in the diffusion furnace to comply with the necessity of processing large diameter wafers needed for highly integrated semiconductor devices. Thereby, a decrease in the rate of productivity for operating such equipment due to its positioning of a reaction gas outlet is prevented.