Tunneling study of inhomogeneous Sb films

Electron tunneling experiments have been performed to study the one-particle density of states in inhomogeneous Sb films. A zero bias anomaly can be well described in terms of the theory of weakly disordered metals. On the other hand, the background conductance at higher voltages exhibits roughly a parabolic shape, which is typical in a metal-oxide-metal tunnel junction. The feature of the band structure in the semimetal disappears completely. This result indicates that an inhomogeneous Sb film constitutes a metallic, degenerate electron gas system at the junction interface. A metastable metallic phase may be stabilized due to a higher disorder. (C) 1997 Elsevier Science Ltd.