Maximum field emission current density of CuO nanowires: theoretical study using a defect-related semiconductor field emission model and in situ measurements

Zufang Lin,Jun Chen,Juncong She,Haibo Gan,Peng Zhao,Ningsheng Xu,Peng Ye,Shaozhi Deng,Yicong Chen

doi:10.1038/s41598-018-20575-y

Zufang Lin, Jun Chen + Show 7 more

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https://doi.org/10.1038/s41598-018-20575-y

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Journal: Scientific Reports	Publication Date: Feb 1, 2018
Citations: 14	License type: open-access

Affiliation: Sun Yat-sen University

Abstract

In this study, we proposed a theoretical model for one-dimensional semiconductor nanowires (NWs), taking account of the defect-related electrical transport process. The maximum emission current density was calculated by considering the influence of Joule heating, using a one-dimensional heat equation. The field emission properties of individual CuO NWs with different electrical properties were studied using an in situ experimental technique. The experimental results for maximum emission current density agreed well with the theoretical predictions and suggested that multiple conduction mechanisms were active. These may be induced by the concentration of defects in the CuO NW. The concentration of defects and the transport mechanisms were found to be key factors influencing the maximum field emission current density of the semiconductor NW. As is limited by the change of resistivity with temperature, only thermal runaway can trigger breakdown in CuO NWs.

Highlights

In this study, we proposed a theoretical model for one-dimensional semiconductor nanowires (NWs), taking account of the defect-related electrical transport process
Further investigation of the role played by the transport process in limiting the maximum current density that can be achieved by a semiconductor NW field emitter is needed
This study proposed a theoretical field emission model for 1D semiconductor NWs, taking into account the contributions made by the concentration of defects and the electrical transport mechanism

Summary

Introduction

We proposed a theoretical model for one-dimensional semiconductor nanowires (NWs), taking account of the defect-related electrical transport process. As is limited by the change of resistivity with temperature, only thermal runaway can trigger breakdown in CuO NWs. The field emission properties of one-dimensional semiconductor nanostructures have been extensively investigated, given their potential application as the electron source in field emission devices such as electron microscopes[1], vacuum electronic devices[2,3], microwave tubes[4], X-ray sources[5,6], and flat panel displays[7,8,9]. Because of their superior antioxidant properties and physical stability, metal oxide semiconductor nanowires (NWs) have attracted increasing attention, and significant efforts have been made to improve their field emission properties[10,11,12,13] Applications such as microwave vacuum electronic devices, X-ray tubes, and high-power terahertz sources require field emitters with high emission current density[14,15]. Further investigation of the role played by the transport process in limiting the maximum current density that can be achieved by a semiconductor NW field emitter is needed

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