Electrical transport in (100)CoSi2/Si contacts

Abstract

A detailed investigation of the electrical transport in (100) CoSi₂/Si contacts is presented. The transport properties of epitaxial CoSi₂ films, obtained both by ion‐beam synthesis and by solid‐state reaction of a Ti/Co bimetallic layer, are compared with the transport properties of conventional polycrystalline CoSi₂ layers. The electrical resistivity, the magnetoresistance, and the Hall effect are measured on Hall bars for temperatures ranging from 1.2 to 300 K and magnetic fields up to 5 T. Very high values of the order parameter k_FL0 are observed, indicating that the investigated samples are of very high purity and crystalline order. In addition, the electric transport at the CoSi₂/Si interface is studied by current‐voltage and capacitance‐voltage measurements on Schottky diode structures for temperatures ranging from 173 to 333 K. Ideality factors close to unity are observed for the highest temperatures, for the lower temperatures the ideality factors are found to increase with decreasing temperatures. The observed temperature dependence of the ideality factor and the Schottky barrier height can be attributed to Schottky barrier inhomogeneities.