The SRP (Spreading Resistance Profiling) spreading resistance test system uses a pair of special point contact probes to step along the sample surface in small increments to measure the spreading resistance value at each point and draw the distribution curve of the sample's resistance, resistivity and doping concentration. The SRP method can not only obtain the electrical properties such as the resistivity distribution of the epitaxial layer, but also determine the thickness of the epitaxial layer and the transition zone distribution of interface impurities.
