Development of Inline Solar Cell Metrology Using Contacted and Contactless Quantum Efficiency

Four batches of 500 production solar cells are evaluated using I-V at 1-Sun, and using both contacted and contactless quantum efficiency techniques. The two quantum efficiency techniques correlate very well in their blue response, both capable of revealing periodic structures in the cells measurement sequence that are related to the manufacturing processes. For each batch, the cell efficiency trends positively with the blue and red response. The contactless quantum efficiency blue response is better able to distinguish differences in emitter formation between cell batches which are processed in different diffusion tubes or furnaces.