Increasing ZnO Growth Rate by Modifying Oxygen Plasma Conditions in Plasma-Assisted Molecular Beam Epitaxy

Kuaile Zhao, Aidong Shen

Department of Electrical Engineering, The City College of New York, New York, USA.

DOI: 10.4236/wjcmp.2012.23026                

Abstract

The authors report that the growth rate of ZnO can be significantly increased by modifying the oxygen plasma conditions in plasma-assisted molecular beam epitaxy. Both the aperture diameter and the distance between the plasma source and the substrate affect the growth rate and the quality of the ZnO films. A short source to substrate distance is essential in achieving higher growth rate, which is explained by reduced chance of oxygen atom collisions to accommodate the short oxygen mean free path at high background pressure. At a shorter source to substrate distance, the growth rate is higher with a larger aperture diameter. The quality of the ZnO thin films grown under different conditions is assessed by x-ray diffraction and room-temperature photoluminescence measurements.

Keywords

ZnO; MBE; Plasma-Assisted MBE; Growth Rate

Conflicts of Interest

The authors declare no conflicts of interest.

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