Enhanced selenium supply in copper indium gallium selenide processes

A substrate carrier, includes: a unitary body fabricated from a single block of graphite, wherein the body comprises a back plate, and a pair of spaced apart, substantially parallel, side rails, wherein each of the side rails comprises: an inwardly facing surface extending outwardly of the back plate; a longitudinally extending selenium vapor bore formed therein, a top end of the selenium vapor bore being open and configured for coupling to a selenium supply container for receiving selenium vapor by gravity, a bottom end of the selenium vapor bore being closed; an inwardly directed selenium vapor channel; a plurality of selenium vapor outlets disposed between the selenium vapor bore and the inwardly directed selenium vapor channel so as provide a plurality of conduits between the selenium vapor bore and the selenium vapor channel; and, a longitudinally extending engagement slot formed in the inwardly facing surface of each side rail adjacent the back plate to engage and hold a substrate in proximity to the back plate.