Screening Phenomena on Oxide Surfaces and Its Implications for Local Electrostatic and Transport Measurements

The determination of local electrical, electrostatic, and transport properties of materials by ambient scanning probe microscopy (SPM) is shown to be strongly affected by the adsorption of charged species. Associated surface screening results in new phenomena including potential retention above the Curie temperature on ferroelectric surfaces and potential inversion on grain boundary−surface junctions. Implications of screening for a variety of SPMs including piezoresponse force microscopy and transport measurements in carbon nanotubes and molecular electronic devices are discussed.