Current–voltage characteristics of the semiconductor nanowires under the metal-semiconductor-metal structure

Abstract

We present a method to calculate the I-V characteristics of semiconductor nanowires under the metal-semiconductor-metal (MSM) structure. The carrier concentration as an important parameter is introduced into the expression of the current. The subband structure of the nanowire has been considered for associating it with the position of the Fermi level and circumventing the uncertainties of the contact areas in the contacts. The tunneling and thermionic emission currents in the two Schottky barriers at the two metal-semiconductor contacts are discussed. We find that the two barriers have different influences on the I-V characteristics of the MSM structure, one of which under the forward bias plays the role of threshold voltage if its barrier height is large and the applied voltage is small, and the other under the reverse bias controls the shapes of I-V curves. Our calculations show that the shapes of the I-V curves for the MSM structure are mainly determined by the barrier heights of the contacts and the carrier concentration. The nearly identical I-V characteristics can be obtained by using different values of the barrier heights and carrier concentration, which means that the contact type conversion can be ascribed not only to the changes of the barrier heights but also that of the carrier concentration. We also discuss the mechanisms of the ohmic-Schottky conversions and clarify the ambiguity in the literature. The possibility about the variation of the carrier concentration under the applied fields has been confirmed by experimental results.

Single GaAs Nanowire/Graphene Hybrid Devices Fabricated by a Position-Controlled Microtransfer and an Imprinting Technique for an Embedded Structure

“…A highconductance state, similar to the intact core, should be retained in this case. 36,37 A simple parallel resistors model is introduced in consideration of the two different resistance states (Section 1, Supporting information). In the model, the cross-sectional resistance of a NW is from a combination of six resistors that can be either high-resistive R SC or low-resistive R NW .…”

“…This does not happen when the NW facets are embedded in a cured photoresist (PR) or contacted to a bottom insulating substrate. A high-conductance state, similar to the intact core, should be retained in this case. , …”

Intrinsic non-ohmic electronic transport properties of the transparent In–Zn–O compound nanobelts under ohmic contact and out of the space charge limited transport region

“…The MSM structure with Schottky barriers can produce similar results to those in figure 2. It has been proved that the shapes of the I-V curve are mainly controlled by the mentalsemiconductor contact under the reverse bias combined with the resistances of the nanostructures [21,40]. The symmetrical nonlinear curve indicates that the barrier heights at the two contacts have the same magnitudes.…”

“…In the region of the reverse biased contact, the current from the metal to the semiconductor under the bias V 1 is mainly dominated by the electron tunneling and thermionic emission processes. It can be expressed as the sum of the two parts by [40]…”