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

Existing procedures for measuring Fe concentrations using low-injection SPV diffusion length measurements on 5-15 Ωcm Si were extended to include arbitrary doping, as well as mid- and high-injection lifetime measurements. This allows the use of fast, contactless lifetime techniques for very sensitive measurement of Fe concentrations on any crystalline silicon material. Thus, the extended technique was slightly more complex than the SPV approach, since the prefactor for determining [Fe]_total changes with the injection level.