A method is described for determining a dopant concentration on a surface and/or in layer region lying close to the surface of a semiconductor sample using an atomic force microscope, whose leaf-spring tip is brought into contact with the semiconductor sample, forming a Schottky barrier, wherein an electric alternating potential is applied between the spring-leaf tip and the semiconductor sample in the region of the Schottky barrier in such a way that a space charge region inside the semiconduct...