Studies of Surface Electrical Properties of Al doped ZnO Nanorods by STM

Shaivalini Singh,Parthasarthi Chakrabarti,Si-Hyun Park,Sumit Vyas

doi:10.5755/j01.ms.23.2.15305

Abstract

Pure and aluminum (Al) doped ZnO (Al:ZnO) nanorods (NRs) were deposited on silicon substrates by the hydrothermal method. The Al composition was kept at 2 % and 5 % for the Al:ZnO NR samples. The surface morphology and structural properties of the pure and Al:ZnO NRs were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The XRD study revealed the hexagonal phase of the ZnO with (101), (002) and (100) peaks and it also revealed that the major orientation of ZnO NRs were along the (002) planes. The SEM micrographs showed perfectly grown ZnO NRs with hexagonal shaped tips. The electrical characterization of the pure and Al:ZnO NR thin film surface was done by scanning tunneling microscopy (STM). Local electron spectroscopy was conducted to measure the tunneling current with respect to the applied bias. The n-type behavior and bandgap of the pure and Al:ZnO NRs were confirmed from the dI/dV – V characteristics. These studies are of fundamental importance for the fabrication of pure and Al:ZnO NR based nanodevices.DOI: http://dx.doi.org/10.5755/j01.ms.23.2.15305

Highlights

Among the various transparent conducting oxide (TCO) materials, ZnO is of particular interest [1, 2]
We studied the electronic properties of Al:ZnO NR films using scanning tunneling microscopy (STM)
Pure ZnO and 2% and 5% Al:ZnO thin films were grown by the hydrothermal method and their structural and electrical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and STM measurements

Summary

INTRODUCTION

Among the various transparent conducting oxide (TCO) materials, ZnO is of particular interest [1, 2]. It is mainly used in photovoltaic cells, organic light-emitting diodes (OLEDs) and flat panel displays [3 – 5]. Al:ZnO NRs are one of the commonly used nanostructures for various devices [3 – 5]. We used the hydrothermal method for the growth of the Al:ZnO NRs. In order to fabricate Al:ZnO NR based devices, a detailed study of their surface and electronic properties is necessary. We studied the electronic properties of Al:ZnO NR films using scanning tunneling microscopy (STM).

EXPERIMENTAL TECHNIQUE

CHARACTERIZATION

RESULTS AND DISCUSSION

CONCLUSIONS