Patent ID: 8759793

Claim:
A method for determining material parameters of a doped semiconductor substrate by measuring photoluminescent radiation comprising the following processing steps: A impinging the semiconductor substrate with an electromagnetic excitation radiation to generate luminescent radiation in the semiconductor substrate, with a temporal progression of an intensity of the excitation radiation being periodically modulated such that a generation rate G of charge carrier pairs, due to the excitation radiation, shows a maximum and a minimum during an excitation period in the semiconductor substrate ( 4 ), and with at least a relative temporal progression of the generation rate G(t) being determined via a time-dependent measurement of the intensity of the excitation radiation, B time-resolved measuring the intensity of the luminescent radiation emitted from a measuring area of the semiconductor substrate, with at least a relative temporal progression of an intensity of the luminescent radiation Φ(t) being measured at least during an excitation period, C determining at least one material parameter of the semiconductor substrate dependent on the temporal progression of the generation rate G(t) and the temporal progression of the intensity of the luminescent radiation Φ(t), in step C an effective life time τ of the semiconductor substrate is determined at least for an excessive charge carrier density Δn max reached during one excitation period, by determining a temporal difference between a maximum of G(t) and a maximum of Φ(t) corresponding thereto.