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.