Epitaxial growth of ZnO films by helicon-wave-plasma-assisted sputtering

• Published in: Physica. B, Condensed matter Condensed matter, 2006-06, Vol.382 (1), p.17-20
• Main Authors: Fu, Guangsheng, Xu, Heju, Wang, Shufang, Yu, Wei, Sun, Wei, Han, Li
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Epitaxy; Exact sciences and technology; Helicon wave plasma; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of specific thin films; Other semiconductors; Physics; Sputtering; ZnO films
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2006.01.535

The epitaxial growth of ZnO films on Al 2O 3 (0 0 0 1) substrates have been achieved at a low-substrate temperature of 400 °C by using a helicon wave-plasma-assisted sputtering technique. X-ray diffraction θ–2θ scan, ω scan and φ scan indicate that the ZnO films have a good c-axis orientation and in-plane epitaxy. The photoluminescence measurement of the films shows that there is only a strong emission peak at 384 nm, and no visible emission related to the structural defects can be detected. A strong absorption in the ultraviolet region and a high transparence of over 85% in visible region are obtained from the optical absorption measurements. Hall-effect measurement reveals that the mobility of the deposited films is 5.0 cm 2/V.s. All above results demonstrate that this newly developed sputtering technique provides a flexible and powerful technique for the growth of high-quality epitaxial ZnO films.