Oxygen flux influence on the morphological, structural and optical properties of Zn1−xMgxO thin films grown by plasma-assisted molecular beam epitaxy

✍ Scribed by S.C. Su; Y.M. Lu; Z.Z. Zhang; B.H. Li; D.Z. Shen; B. Yao; J.Y. Zhang; D.X. Zhao; X.W. Fan

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 657 KB
• Volume: 254
• Category: Article
• ISSN: 0169-4332
• DOI: 10.1016/j.apsusc.2008.01.132

✦ Synopsis

The Zn 1Àx Mg x O thin films were grown on Al 2 O 3 substrate with various O 2 flow rates by plasma-assisted molecular beam epitaxy (P-MBE). The growth conditions were optimized by the characterizations of morphology, structural and optical properties. The Mg content of the Zn 1Àx Mg x O thin film increases monotonously with decreasing the oxygen flux. X-ray diffractometer (XRD) measurements show that all the thin films are preferred (0 0 2) orientated. By transmittance and absorption measurements, it was found that the band gap of the film decreases gradually with increasing oxygen flow rate. The surface morphology dependent on the oxygen flow rate was also studied by field emission scanning electron microscopy (FE-SEM). The surface roughness became significant with increasing oxygen flow rate, and the nanostructures were formed at the larger flow rate. The relationship between the morphology and the oxygen flow rate of Zn 1Àx Mg x O films was discussed.