Observation of Langmuir-Blodgett Films by Scanning Tunneling Microscopy

Abstract
Langmuir-Blodgett films of cadmium-arachidate have been studied by scanning tunneling microscopy (STM). Substrates of gold and graphite are used to make mono- and bilayer films. The image of the individual molecule cannot be obtained for the films on gold, but the data indicate disturbances on the tunneling current caused by the films. As for the films on graphite, the molecular images with a spacing of 0.4–0.7 nm are recognized in some frames of the variable tunneling current image recorded on videotape. Possible mechanisms of the imaging are discussed.