Application of C-V characteristics of semiconductor-insulator semiconductor structures for investigation of charge state in thin dielectric layers

A new technique for determining the amount and the mean spatial depth of charge in dielectric layers is presented. This technique is based on high-frequency capacitance-voltage (C-V) measurements of the semiconductor-insulator-undoped semiconductor system. Using an undoped semiconductor as a gate material allows one to estimate fixed oxide charge and its centroid in the frame of one nondestructive measurement. The possibilities of the technique are illustrated by experimental results of the influence of hydrogen modification and X-ray irradiation on the charge in dielectrics.