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Articles you may be interested inExtraction of Schottky diode parameters from current-voltage data for a chemical-vapor-deposited diamond/silicon structure over a wide temperature rangeThe low-frequency (1/f ) noise and current-voltage characteristics of GaAs and Si Schottky barrier diodes are studied over a wide temperature range: 77-400 K. The peculiarities of temperature and current dependences of the spectral intensity ͑SI͒ of current fluctuations S i (I,T) ͑a specific increase of the SI with decrease in temperature and a deviation from a quadratic dependence of the S i -I 2 form͒ are explained adequately by the influence of a predominantly local barrier height lowering at a Schottky barrier contact ͑SBC͒, most likely at its periphery. The Gaussian barrier height distribution at SBCs does not explain these peculiarities. It is shown that the 1/f noise at SBCs approaches the ''ideal'' noise of the S i -I ␤ / f ␣ form, where ␤ϭ2 and ␣ϭ1, as the temperature increases. The explanation for the ''low-temperature anomaly'' in SBCs ͓an increase in the ideality factor n and a decrease in the measured ͑from a saturation current͒ barrier height bm with decrease in temperature, a weak variation of their product bn ϵn bm in this case, and the character of the temperature dependence n(T) in the form of nХ1ϩT 0 /T ͑''T 0 effect''͔͒ is presented. This explanation is based on a fundamental property of real SBCs-the nonlinear bias dependence of the barrier height resulting in a growth of the ideality factor with a bias voltage ͑current͒ increase. The other necessary condition for revealing the ''low-temperature anomaly'' is the inclusion in theory of the fact that the n and bm measurements are performed at the same current for all temperatures. An expression for the flatband barrier height b f is derived. It takes into account the nonlinear bias dependence of the barrier height and the n(I) dependence which follows from it. On the basis of this expression the conditions are defined at which a simple approximation for b f is valid: b f Х bn ϵn bm .

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On the basis of numerical analysis, a model of the intimate metal-semiconductor Schottky-barrier (SB) contact is proposed. According to this model, the Fermi-level pinning at the contact is due to high density of electron surface states in equilibrium with the metal, whereas the IV characteristic distortions (deviation from ideality) are due to a continuous (and/or discrete) spectrum of the energy-and coordinate distributed (in the general case) nearsurface states in equilibrium with the semiconductor. This model amplifies the Bardeen model for actual SB contacts that is limited by the assumption of the presence of an intermediate insulating layer. However, the assumption is not necessarily fulfilled for the contacts manufactured using currently available technologies.

Influence of the nonlinear bias dependence of the barrier height on measured Schottky-barrier contact parameters J. Appl. Phys. 109, 113718 (2011); 10.1063/1.3587233 Barrier heights of real Schottky contacts explained by metal-induced gap states and lateral inhomogeneitiesObservation of quantized conductance in split-gate In 0.53 Ga 0.47 As/In 0.77 Ga 0.23 As/InP point contacts using Cr/Au p -InP Schottky barriers