Electric Current and Noise in Long GaN Nanowires in the Space-Charge Limited Transport Regime

TL;DR

This study investigates electric current and noise in GaN nanowires, revealing how space-charge effects influence noise characteristics and device performance, with implications for nanowire-based electronic applications.

Contribution

It provides new insights into the noise behavior and current regimes in GaN nanowires under space-charge limited conditions, highlighting size-dependent effects.

Findings

Normalized noise increases as NW width decreases at low voltages.

In the SCLC regime, noise intensity can increase up to 10,000 times.

Spectral shape shifts towards a slope of -3/2 in the SCLC regime.

Abstract

We studied electric current and noise in planar GaN nanowires (NWs). The results obtained at low voltages provide us with estimates of the depletion effects in the NWs. For larger voltages, we observed the space-charge limited current (SCLC) effect. The onset of the effect clearly correlates with the NW width. For narrow NWs the mature SCLC regime was achieved. This effect has great impact on fluctuation characteristics of studied NWs. At low voltages, we found that the normalized noise level increases with decreasing NW width. In the SCLC regime, a further increase in the normalized noise intensity (up to 1E4 times) was observed, as well as a change in the shape of the spectra with a tendency towards slope -3/2. We suggest that the features of the electric current and noise found in the NWs are of a general character and will have an impact on the development of NW-based devices.