Theory and Realization of a Two-Layer Hall Effect Measurement Concept for Characterization of Epitaxial and Implanted Layers of SiC

Abstract

AbstractEpitaxial and implanted layers are generally characterized by Hall effect measurements using a pn-junction as electrical insulation of the layer from the substrate. Due to defects, low doping concentrations or thin layers the resistivity of epitaxial or implanted layers is comparable to the resistivity of the pn-junction and the substrate. This results in inefficient electrical insulation between both regions. To be able to determine the properties of epitaxial or implanted layers even in the case of substantial leakage current we developed a two-layer Hall effect measurement concept. This concept is based on the conventional van der Pauw technique applied to the layer and the substrate separately. In addition the current-voltage characteristic of the pn-junction is measured and modeled in the analysis as an ohmic resistor.This two-layer concept is applied to epitaxial grown SiC and the results are compared with conventional van der Pauw technique. In addition both techniques are compared with the results of capacitance-voltage (CV) measurements and secondary ion mass spectroscopy (SIMS).