| Title |
Rapid Thermal Annealing Effects on the Electrical and Structural Properties of ITO Thin Films Deposited at Room Temperature |
| Authors |
김성진(Sung Jin Kim); 최균(Kyoon Choi); 최세영(Se Young Choi) |
| DOI |
https://doi.org/10.3365/KJMM.2013.51.9.691 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
ITO; rapid thermal annealing; RF magnetron sputtering; transparent conducting film |
| Abstract |
Abstract: Transparent and conductive Indium Tin Oxide (ITO) thin films were prepared on glass substrates at room temperature (RT) by a RF magnetron sputtering method. The ITO films sputtered at room temperature had an amorphous structure and uniform surface morphology with low planner density. We report the influence of rapid thermal annealing (RTA) treatment on the microstructure, optical and electrical properties of the ITO thin films. Rapid thermal annealing (RTA) was carried out for 2 min, 4 min, 5 min, 8 min and 10 min at 500 ℃ in 98%N2 + 2%H2 ambient gas. This study provides data about the microstructure and optical properties of ITO thin films with thicknesses of around 100 nm. The experimental results showed that the post growth RTA temperature has a significant effect on the properties of ITO thin films. The preferred orientation along the (222) plane, and the average grain size, measured from TEM micrographs, ranged from 5 to 30 nm. The average optical transmittance in a wavelength range of 200-800 nm increased from 74% to 88% after rapid thermal annealing at 500 ℃, where the highest value of the figure of merit was obtained. The resistivity decreased by 500 ℃ at 5 min, which was the annealing temperature, and after that the resistivity increased. The major factor of the resistivity change was the change of the carrier concentration. In addition to the increase in carrier concentration, RTA at 500 ℃ at 5 min caused the band gap energy of the ITO thin films to rise linearly. |