Abstract: A self-aligning mating structure of a substrate support element is connected to an alignment guide. The combination of the self-aligning mating structure and the alignment guide assures that the element properly seats in a complementary mating structure shaped opening in a susceptor as the susceptor is moved into the processing position. An end of the substrate support element opposite to and removed from the self-aligning mating structure is weighted. Thus, the substrate support element remains properly seated in the susceptor throughout the process cycle. The end of the substrate support element opposite to and removed from the self-aligning mating structure also includes a support structure. As the susceptor is lowered from the processing position to the load/unload position, the support structure contacts the bottom of the reaction chamber or other surface in the reaction chamber.