Si Epitaxial Growth of Extremely Uniform Layers by a Controlled Supplemental Gas Adding System

Abstract

A new approach to uniform growth, which directly modulates and controls the reactant gas concentration distribution within a reactor, has been proposed. A rotary disk (pancake) type reactor with a controlled supplemental gas adding system for regions of insufficient epitaxial layer thickness was designed and fabricated after consideration of gas flow patterns and reaction gas concentration distribution within the reactor. Simulation and control methods were developed to optimize the parameters of the multiple supplemental gas nozzles so that a uniform layer thickness distribution over a large range of susceptor radial directions could be achieved. Experiments using three supplemental nozzles showed that this system and control method could achieve deviations in thickness of less than ± 1% both within a wafer and within a growth lot.