Variable temperature hardware and methods for reduction of wafer backside deposition

A process tuning kit useful in a chemical deposition apparatus, the kit comprising a carrier ring, set of three horseshoes and sets of three shims wherein:

• each of the shims has an upper surface, a lower surface parallel to the upper surface, an end wall, a U-shaped sidewall extending from the end wall and a bore of the shim extending between the upper and lower surfaces, a first set of three shims having the same thickness and a second set of the shims having a different thickness than the first set of shims;
• each of the horseshoes has an upper surface, a lower surface parallel to the upper surface, an end wall, a U-shaped side wall extending from the end wall, a bore of the horseshoe extending between the upper and lower surfaces, and a slot opening in the end wall and extending less than half way across the upper surface, the bore of the horseshoe having the same diameter as the bore of the shims;
• the carrier ring having an upper surface, a lower surface parallel to the upper surface, an outer side wall, an inner side wall, and three alignment pins extending from the lower surface.