Preparation of Cu-based delafossite thin films and its antibacterial properties

• Main Authors: Yung-Po Wang, 王永伯
• Other Authors: Te-Wei Chiu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/9vabp5

碩士 === 國立臺北科技大學 === 材料科學與工程研究所 === 100 === Transparent conducting oxides (TCOs) are attracting more and more attention. In general, most of the known TCOs are n-type materials. However, delafossite films, such as CuYO2, CuCrO2, and CuScO2, etc., have attracted considerable scientific and technological attention. Up to now, most delafossite films have been prepared by vacuum-based methods with advantages of the thin film uniformity, less impurity content and well performance, such as pulsed laser deposition (PLD) and magnetron sputtering. The advantages of delafossite thin films prepared by chemical solution deposition is the capability to coat materials of various shapes and large area, to control the composition easily for obtaining solutions of homogeneity and controlled concentration without using expensive equipment. Delafossite thin films are prepared on glass substrates by ratio frequency (rf) magnetron sputtering and chemical solution deposition. All the conditions in both deposition methods are investigated in order to produce delafossite thin films with better performance in conductivity and optical transmittance. Annealing conditions are investigated in order to produce delasossite phase p-type conductive thin films, such as ambient gas and temperature. The crystalline structure of thin films was confirmed by glancing incident angle X-ray diffraction. Field emission scanning electron microscope was used to observe the surface morphology and cross-section of thin films. The transmittance of the thin films in visible region was measured by UV-Visible spectrometer. The electrical properties were obtained by four-point-probe. The hole concentration and hole mobility were measured by Hall Effect Analyzer, respectively. In this research, the anti-bacterial properties of delafossite thin film surfaces against Escherichia coli (E. coli) bacteria were investigated. Copper based delafossite thin films were prepared on glass substrates by sputtering and chemical solution deposition, respectively. Annealing conditions, such as ambient gas and temperature, are investigated. The ISO 22196 method was utilized to evaluate the colony forming unit (CFU) of E. coli on the thin film surface after incubation. The experimental results show the thin film surface exhibiting superior antibacterial performance and high optical transparency of thin films. A novel transparent anti-bacterial coating has been first demonstrated in present study.