中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 20 No. 12 December 2010 |
N-doped ZnO films deposited by magnetron sputtering
(1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. Material Science Department, CENIMAT/I3N and CEMOP/UNINOVA, FCT-UNL,
Campus de Caparica, 2829-516 Caparica, Portugal;
3. Ion Beam Laboratory, Physics Department, Institute of Technology and
Nuclear EN. 10, 2686-953 Sacavem, Portugal;
4. Center of Molecular Chemistry-Physics, Institute of Nanoscience and Nanotechnology,
Complexo Interdisciplinar, IST 1049-001 Lisboa, Portugal)
Abstract:N-doped ZnO films were radio frequency (RF) sputtered on glass substrates and studied as a function of oxygen partial pressure (OPP) ranging from 3.0´10−4 to 9.5´10−3 Pa. X-ray diffraction patters confirmed the polycrystalline nature of the deposited films. The crystalline structure is influenced by the variation of OPP. Atomic force microscopy analysis confirmed the agglomeration of the neighboring spherical grains with a sharp increase of root mean square (RMS) roughness when the OPP is increased above 1.4´10−3 Pa. X-ray photoelectron spectroscopy analysis revealed that the incorporation of N content into the film is decreased with the increase of OPP, noticeably N 1s XPS peaks are hardly identified at 9.5´10−3 Pa. The average visible transmittance (380−700 nm) is increased with the increase of OPP (from ~17% to 70%), and the optical absorption edge shifts towards the shorter wavelength. The films deposited with low OPP (≤ 3.0´10−4 Pa) show n-type conductivity and those deposited with high OPP (≥ 9.0´10−4 Pa) are highly resistive (> 105 W∙cm)
Key words: ZnO; oxygen partial pressure; magnetron sputtering; transmittance