Variation in boron doping by planar diffusion – a comparative study of computational hydrodynamics and experimental observations

Abstract

Resistivity maps for Si wafers processed using BN solid sources and hydrogen injection were compared to convective flow patterns predicted computationally. The convective flow patterns were found to mirror the resistivity maps, with low velocity flow domains being associated with high resistivity regions on the wafer and high velocity flow with low resistivity regions. Subtle changes in both the flow patterns and resistivity maps as a function of location within the furnace were consistently reflected in both computed flow domains and measured resistitivies. Finally, axially eccentric placement of the wafer–source stack was found to promote convection between wafer–source pairs by as much as a factor of five.

Keywords

SI WAFERS RESISTIVITY MAPS FURNACE FLOW PATTERNS CONVECTION

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