Electrical transport in (100)CoSi2/Si contacts

Abstract

A detailed investigation of the electrical transport in (100) CoSi,/Si contacts is presented. The transport properties of epitaxial CoSiZ 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 CoSi, 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&s are observed, indicating that the investigated samples are of very high purity and crystalline order. In addition, the electric transport at the CoSiz/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 idea&y 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. 0 2995 American Institute of Physics.

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