Investigations of mis structure inhomogeneities using a scanning mercury probe

Capacitance and conductance of Hg-SiO2-Si structures were measured using a small mercury probe as metal electrode. The measurements were carried out during continuous scanning of the investigated surface. The results were displayed as three-dimensional plots. The accuracy of the measurements was about 1% and the resolving power was up to 20 μm. The measurements show that the insulator and the semiconductor themselves are rather homogeneous over the area as well as the usual “fast” surface state parameters. On the contrary the charge captured in the insulator is rather inhomogeneous. The existence of small regions showing anomalously high recombination was proved once more.