Wafer carrier assembly with improved temperature uniformity

A wafer carrier for use in a system for growing epitaxial layers on one or more wafers by chemical vapor deposition (CVD), the wafer carrier comprising:

• a base including a generally planar bottom surface and a top surface that is generally parallel to the bottom surface, wherein the top surface includes a plurality of platforms extending above the top surface of the base;
• and
• a thermal cover defining a plurality of pockets, wherein 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 of the base;
• wherein the base includes a plurality of second pedestals that extend from top surfaces of the plurality of platforms for supporting the one or more wafers in such a way that the one or more wafers are free of direct contact with the thermal cover during operation;
• wherein the top surface of the base includes a sloped center recessed section at a center region of the base in areas between the platforms, the thermal cover covering the sloped center recessed section, wherein the sloped center recessed section has a planar floor that extends between first and second steps formed in the top surface and sloped downward toward a center of the base.