Electrostatics of the nanowire radial 𝑝-𝒾-𝑛 diode

Abstract

In this paper, the electrostatic theory of the nanowire radial core-shell 𝑝-𝒾-𝑛 homojunction has been considered. The calculations carried out show that, in contrast to a planar 𝑝-𝒾-𝑛 diode, the built-in electric field of the nanowire radial 𝑝-𝒾-𝑛 diode proves to be inhomogeneous. This field reaches its maximum in the region of the i-layer adjoining the core. When moving away the i-layer from the nanowire center, the degree of field inhomogeneity decays, and both edge values of the field in the i-layer eventually reach the magnitude, which takes place in an analogous planar 𝑝-𝒾-𝑛 diode. This magnitude can be both higher and lower than the maximal field in the nanowire 𝑝-𝒾-𝑛 diode (depending on doping conditions). Simultaneously, the capacitance of the nanowire p-i-n diode can both increase and decrease in its value, going, at the same time, to weak voltage dependence inherent to the planar 𝑝-𝒾-𝑛 diode.