Determination of the diffusion length of minority charge carriers in a semiconductor from the dynamic nonequilibrium I-V characteristics of MIS structures

A method for determination of the diffusion length L (de) of minority charge carriers in a semiconductor from the dynamic nonequilibrium I-V characteristics of metal-insulator-semiconductor (MIS) structures is proposed. The method makes it possible to exclude the effect of bulk generation in a semiconductor on L (de) and decrease the temperature of measurements. The possibility of investigating the effective L (de) profile in the semiconductor surface layer is shown for the case of nonuniform depth distribution of electrically active defects in a material. The values of L (de) in MIS structures on silicon used in integrated-circuit technology are investigated. The effect of the internal gettering of defects in silicon and the irradiation of MIS structures by low-energy electrons (10-30 keV) on the effective L (de) profiles in the surface layer of a semiconductor is considered.