Investigations of local electrical properties using tunneling/atomic force microscope with a quartz tuning fork nearfield sensor

Ability to determine local electric surface properties with a high resolution is a key issue in many modern industrial applications. In this article, authors will describe low-cost and reliable methods for investigations of electrical surface properties with a nanoscale resolution using a homebuilt modular tunneling/atomic force microscope with a quartz tuning fork as a probe. We will present the architecture of the designed system and the calibration method of the applied sensor. In our work, the usage of the tunneling atomic force microscope in the high-resolution investigations of the surface topography and identification of local spots where the tunneling current is observed will be demonstrated. We will also present current–voltage (I–V) spectroscopy performed on a gold thin film sputtered on silicon substrate and a highly oriented pyrolitic graphite (HOPG) surface, which we obtained in air ambient and at room temperature.