9.1.1.4.1 Theory of field desorption

This chapter discusses applications of field ionization and theory of field desorption. The field ion microscope has been applied to a wide variety of problems, particularly in the areas of metallurgy and surface science. One of its most unique applications in surface science involves the investigation of the diffusion and clustering of individual atoms on an atomically well-defined surface. The field ion microscope has also been used to investigate various surface chemical reactions in relation to problems in catalysis and corrosion. In the area of quantitative analysis, field ionization offers the advantage of reduced fragmentation of the parent molecule. Efforts have also been undertaken to develop field ionization sources for applications in lithography. Field desorption is the removal of an atom or molecule from a solid surface by a high electric field. Field evaporation is a special case of field desorption which refers to the high-field removal of substrate surface atoms. The process of field desorption is understood qualitatively in terms of one-dimensional potential energy diagrams. Potential energy diagram illustrating the field desorption process is schematically represented.