Multicrystalline silicon solar cells: gettering optimization and characterization

Three multicrystalline silicon materials were used in preliminary experiments in preparation for a planned comprehensive gettering study on several industrial solar cell materials. Two processes commonly used to upgrade material quality were investigated; phosphorus gettering and aluminum-alloying. Microwave-detected photoconductance decay measurements of minority carrier lifetime and detailed analyses of full solar cells were used to determine the response to the gettering processes. Lateral nonuniformities were shown to be significant in these multicrystalline materials. Identification of the nature of the nonuniformities is important in developing an understanding of gettering effects