THE INFLUENCE OF INVERSION SURFACE-LAYERS ON THE EVALUATION OF THE INTERFACE STATE ENERGY-DISTRIBUTION FROM SCHOTTKY-DIODE I-U CHARACTERISTICS

The effect of an inversion layer on the interface parameters of the Schottky-barrier diode determined by analysis of its I-U characteristics is discussed. It is shown that the formation of the inversion layer at the semiconductor surface reduces the dependence of the barrier height on bias, similarly as the presence of the interface states that are in equilibrium with the metal Fermi level. Expressions for evaluating the density of interface states and the relative interfacial layer thickness are derived. On the basis of these expressions the influence of the inversion layer on the measured density of interface states in silicon and GaAs Schottky diodes is estimated.