ELECTRICAL-PROPERTIES OF CRYSTALLIZED SEMIINSULATING POLYCRYSTALLINE SILICON FILMS

The electrical characteristics of the crystallized semiinsulating poly crystalline silicon (SIPOS) film were studied, and its electrical cond uction was investigated. It is found that the electrical characteristi cs of the SIPOS film can be explained by the thermionic emission mecha nism. Since the oxygen concentration in the film is higher, the band g ap is wider and the resistivity and activation energy are increased. B y considering the segregation effect of phosphorus, the surface densit y of grain boundary traps of the crystallized SIPOS film was derived a nd the relationship was clarified between the oxygen concentration and the surface density of traps. As the oxygen concentration is increase d, the surface density of traps increases. The electrical characterist ics of the SIPOS film can be explained better if a Gaussian distributi on rather than a single level is assumed for the energy of the grain b oundary trap.