A substrate holder comprises a generally circular planar body, the body having greater than or equal to two pairs of diametrically opposed, parallel flat edges, and wherein the substrate holder is configured to fit on a generally circular susceptor within a processing chamber. In some embodiments the substrate holder has four pairs of diametrically opposed, parallel flat edges, whereby the substrate holder is substantially octagonal. Furthermore, in some embodiments the substrate holder covers less than eighty percent of the susceptor area. A method of processing a substrate using the substrate holder includes: loading the substrate into a recess in the substrate holder; transferring the substrate holder through a loadlock into the processing chamber, the substrate holder being presented with a smallest cross-section aligned for passage through the loadlock; placing the substrate holder on the susceptor; and processing the substrate. The substrate holder may carry a plurality of substrates. Alternatively, the substrate holder may carry a single large substrate, the substrate being trimmed to fit the substrate holder.