Abstract: A wafer carrier includes a base including a generally planar bottom surface and a top surface that includes a plurality of platforms extending above the top surface. The wafer carrier includes a thermal cover defining a plurality of pockets. The thermal cover is configured to be coupled to the base by at least one fastener and the plurality of pockets are arranged such that each pocket of the plurality of pockets is aligned with a corresponding platform of the plurality of the platforms when the thermal cover is supported by a plurality of first pedestals that extend from the top surface of the base. A plurality of second pedestals are located along the plurality of platforms for supporting the one or more wafers, wherein each platform includes at least one second pedestal that extends from a top surface of the platform for supporting one wafer.

Abstract: Systems and methods are described herein for improving the overall thickness control and the radial thickness profile of epitaxially-grown films or layers on wafers. Continuous, in situ measurement of thickness at a radially inner region and a radially outer region are used in embodiments to control corresponding precursor and/or dilution gas flow rates. Such measurements can be made using white light reflectometry through a viewport in the reactor housing.