Barrier height enhancement of the Schottky barrier diode using a thin uniformly-doped surface layer

Abstract

An analytic model for the barrier height enhancement of the Schottky barrier diode with the Mnp (or Mpn) structure, which considers the uniformly doped surface layer and the surface properties of the metal-semiconductor system, is presented. The maximum potential barrier and its precise location including the effect of the image-force potential have been calculated, which shows that the effective barrier height for the majority carriers without considering the image-force lowering will give erroneous predictions if the doped surface layer is very shallow or lightly doped. The built-in voltage of the Mnp structure based on the interfacial layer theory has also been calculated, which gives the exact dependence of the built-in voltage on the interface properties of the metal-semiconductor contact and the dose of the doped surface layer. Numerical results of the developed model have been computed and discussed, which may serve as the guide for the fabrication of the Schottky barrier (SB) and MIS solar cells with higher barrier height.