Investigation of Tantalum Oxide Films Prepared by Magnetron Sputtering for the Applications of All Solid State Electrochromic Devices

• Main Authors: Kuang-ILiu, 劉光益
• Other Authors: Jow-Lay Huang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/07715871516041384469

碩士 === 國立成功大學 === 材料科學及工程學系碩博士班 === 98 === Recent years electrochromism have been extensively investigated due to their potential applications such as smart window of architecture to modulate the room’s temperature. In this study, inorganic-solid-state electrolyte tantalum oxide thin films were deposited by D.C. reactive magnetron sputtering in order to improve the leakage and deterioration of the traditional liquid electrolyte. The parameter of O2 atmospheres (the flow rate range : 1~20sccm) and powers (35~100W) were varied to investigate their effects on composition, microstructure, optical properties and electrochromic properties. Experimental results indicated that tantalum oxide thin films were amorphous, near stoichiometric, porous with loose fibrous structure, and highly transparent in nature. As the oxygen flow rate and power increased, the refractive index increased however the current density and optical transmission change of the film decreased. It was showed that the Ta2O5 films with high packing density and low porous structure were unfavorable for ions transmission. At the oxygen flow rate of 3sccm and 50W, the transmission change between colored and bleached states at a wavelength of 550nm was 56.7%. The film has been observed with high optical density. Compared with Ta2O5/WO3 film and WO3 film, cyclic voltammetry curves were very close. It showed that tantalum oxide films had the capability of conducting ions. Assembled the electrochromic semi-device performsafter with 100 cycles test has good transmittance change and good quality stability. Finally, Ta2O5 thin film with best electrochromic properties was used as a ion conducting layer to pack on the solid electrochromic device with electrochromic layer of WO3 and counter electrochromic layer of NiOx. Then the device was set to measure its electrochromic properties. The all solid electrochromic device was manufactured as the multilayer of Glass/ITO/WO3/Ta2O5/NiOx/ITO/Glass. Optical transmittance change of the device was increased by the applied voltage from ±1V to ±5V with transmission change of 66.5%.