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Scanning tunneling microscopy (STM) and spectroscopy (STS) investigations are made of highly oriented pyrolytic graphite (HOPG) in air and Langmuir‐Blodgett (LB) liquid crystalline films on HOPG. Charge density waves (CDW) on LB film surface and induced conductivity of LB film are discovered. Theoretical models for different tunneling mechanisms, explaining the experimental results are suggested. The influence of tip–sample interaction on forming additional resonant tunneling channels is analyzed. It is demonstrated, that the accurate information about electronic structure and symmetry of resonant states is necessary for correct STM data interpretation.

Structural properties of porous silicon were studied with atomic-force microscopy (AFM) and optical second harmonic generation (SHG). Depending on etching conditions, the SHG response was observed to be either anisotropic, showing C2v symmetry, or isotropic. This correlated with AFM observations of quasi ordered structures in the first case. The Si etching process was studied by in situ SHG measurements.

Force and surface devices with tunneling sensor—scanning tunneling and atomic force microscopes—are constructed. Thermal drift, seismic and electronic noise are eliminated in precise experiments. The tunneling sensor is proved to be advantageous for large scale images and force versus distance measurements with high dynamic range and subnanometer resolution. The influence of adsorbate on scanning tunneling microscope (STM) images of graphite is demonstrated. The holes 2 nm in diameter are produced on graphite exposed at air using STM.