Iron detection in crystalline silicon by carrier lifetime measurements for arbitrary injection and doping

• DOI: 10.1063/1.1637136
• Publication Date: 2004-01-25T04:12:46Z
• Authors: D. H. Macdonald; L. J. Geerligs; A. Azzizi
• Keywords: Carrier lifetime

An existing technique for accurate measurement of iron in silicon, which was previously restricted to low injection and a narrow doping range, has been extended arbitrary levels. This allows contactless lifetime techniques be used very sensitive rapid detection under wide range conditions. In addition, an easily measured unambiguous “fingerprint” silicon identified. It is based on the invariant nature excess carrier density at injection-dependent curves, before after iron–boron pair dissociation, cross over. characteristic crossover point lies 1.4 2.0×1014 cm−3, provided only that boron concentration below 5×1016 cm−3. To demonstrate value these techniques, they have applied photovoltaic-grade cast multicrystalline wafers.