A substrate heating apparatus includes: a plurality of heating lamps disposed on a chuck stage; a window disposed on the chuck stage and including a window base and a central lens, wherein the chuck stage and the window are each configured to support a substrate above the heating lamps; and a mirror disposed between the heating lamps and the chuck stage, the mirror including a mirror base, a central reflector, and an edge reflector, wherein the plurality of heating lamps are configured to heat the substrate by emitting light through the window onto the substrate and emitting light onto the mirror, wherein the mirror is configured to reflect the light through the window onto the substrate, including reflecting portions of the light via the central and edge reflectors, and wherein the central lens is configured to focus the light onto the central portion of the substrate.