Characterization of n-type Mono-crystalline Silicon Ingots Produced by Continuous Czochralski (Cz) Technology

Continuous Czochralski (Cz) technology has been developed to address the high cost drivers of the traditional Cz technology for producing n-type wafers which are used to make the silicon based solar cells with the highest energy conversion efficiency. Continuous Cz technology overcomes the shortcomings of the traditional Cz in low ingot output from each crucible and large axial variation in resistivity and interstitial oxygen across the ingot, two of the drivers for the high wafer cost. In this work, five 2-meter long ingots pulled by continuous Cz from a single crucible were characterized for the minority carrier lifetime, resistivity, interstitial oxygen and substitutional carbon concentrations. In addition, the wafers cut from these ingots were made into cells at both Georgia Institute (nPERT with front junction) and ECN (n-Pasha). Equivalent cell performance from these ingots has been achieved.