Embodiments of the current invention describe methods of forming different types of crystalline silicon based solar cells that can be combinatorially varied and evaluated. Examples of these different types of solar cells include front and back contact silicon based solar cells, all-back contact solar cells and selective emitter solar cells. These methodologies all incorporate the formation of site-isolated regions using a combinatorial processing tool and the use of these site-isolated regions to form the solar cell area. Therefore, multiple solar cells may be rapidly formed on a single crystalline silicon substrate for use in combinatorial methodologies. Any of the individual processes of the methods described may be varied combinatorially to test varied process conditions or materials.