Mg and Ga co-doped ZnO (MgxGayZnzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93, MGZO), Mg and Al co-doped ZnO (MgxAlyZnzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93, MAZO), Mg and In co-doped ZnO (MgxInyZnzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93, MIZO), Mg doped ZnO (MgxZnyO, x + y = 1, x = 0.05 and y = 0.95, MZO) and pure ZnO thin films have been prepared on the glass substrates by RF magnetron sputtering. Their structural, morphological, compositional, electrical, and optical properties were characterized. The X-ray diffraction patterns showed that all the thin films were grown as a hexagonal wurtzite phase with c-axis preferred orientation without secondary phase. The (0002) peak positions of MGZO, MAZO and MIZO thin films were not significantly changed. The cross-section field emission scanning electron microscopy images of MGZO, MAZO and MIZO thin films showed that all the thin films have a columnar structure with dense morphology. The MGZO thin film showed the best electrical characteristics in terms of the carrier concentration (3.7 × 1020/cm3), charge carrier mobility (8.39 cm2/Vs), and a lower resistivity (1.85 × 10- 3cm). UV-visible spectroscopy studies showed that the MGZO, MAZO and MIZO thin films exhibit high transmittance over 85% in the visible region. The MGZO thin films showed wider optical band gap energy of 3.75 eV.
Bibliographical noteFunding Information:
This study was supported by the Human Resources Development program (No. 20124010203180 ) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea Government Ministry of Trade, Industry and Energy and financially supported by the Ministry of Knowledge Economy (MKE) , Korea Institute for Advancement of Technology (KIAT) and Honam Leading Industry Office through the leading Industry Development for Economic Region.
© 2014 Elsevier B.V.
- Quaternary compound
- RF magnetron sputtering
- Transparent conducting oxide