Susceptor for deposition apparatus

An apparatus for depositing a layer of a material on a wafer comprising:

• a deposition chamber having a sidewall;
• a circular susceptor plate having a continuous surface in the chamber and mounted on a shaft for rotation, said susceptor plate having a surface at the top thereof and a plurality of support posts projecting from said surface, said support posts being arranged in spaced relation in a pattern which permits a wafer to be seated on the support posts with the wafer being spaced from the surface of the susceptor plate;
• and wherein the support posts on the susceptor plate are of a length to space the wafer from the surface of the susceptor plate a distance sufficient to allow a deposition gas to flow and/or diffuse between the surface of the susceptor plate and substantially the entire back surface of the wafer but still allow heat transfer form the susceptor plate to the wafer mainly by conduction;
• a gas inlet into the chamber through said sidewall;
• a gas outlet from the chamber said gas outlet formed through said sidewall and opposite said gas inlet;
• and
• means for heating the susceptor plate.