Determination of the Magnitude and Centroid of the Charge in a Thin-film Insulator by CV and Kelvin Probe Measurements

This paper describes how capacitance–voltage (CV) and Kelvin probe (KP) measurements can be combined to determine the magnitude and centroid of the electric charge in a thin-film insulator. The technique is demonstrated on three films of relevance to silicon solar cells: aluminium oxide, amorphous silicon nitride and silicon dioxide. Since the charge within these films is of different magnitudes, locations and polarity, they offer a good selection with which to demonstrate the combined CV and KP technique.