镀膜温度对WO_3薄膜的电色性能影响

Effect of Deposition Temperature on Electrochromic Properties of WO_3 Thin Films

采用直流反应磁控溅射设备制备WO3薄膜,对一组温度在47~400℃范围制成的WO3薄膜进行恒电流的电化学循环试验;利用紫外-可见-近红外分光光度计测试WO3薄膜的电色性能。结果表明,染色后WO3薄膜的光学吸收,以及染色效率在波长为1 000~2 500 nm的范围内,温度400℃以下,随镀膜温度的升高而提高。分析认为,由于薄膜在300℃开始进入结晶态,350℃以上结晶化程度增加,从而在高温范围（350~400℃）,光学与电化学特性上的改变是由于薄膜的结晶度的增加而导致的。在本实验中,注入电量为10 mC/cm2,可使光学可控量在太阳光谱范围内保持相当稳定,而这种可控量已经能够很好地满足电色应用的需求。本研究为在太阳光谱范围内更有效地利用WO3薄膜的电色性能提供实验依据。

The influence of deposition temperature on the electrochromic properties of reactively sputtered WO3 films was investigated.A set of WO3 films produced in the temperature range of 47~400℃ and electrochemically cycled with a constant current supply.The electrochromic property measurements were performed using a UV-Vis-NIR spectrophotometer.The results show that optical absorption after coloration,and hence the coloration efficiency of the films,significantly increased with increasing deposition temperature（up to 400℃） in the wavelength range of 1 000～2 500 nm.Analysis shows that the crystallization of the WO3 started at 300℃ in a low degree,and was enhanced rapidly after 350℃.Therefore,the changes in optical and electrochemical properties of the films were due to the increase of the degree of crystallization.In present work optical modulation across the solar spectrum remained fairly constant for charge injection of 10 mC/cm2,quite satisfactory for the application of all films in electro chromic devices.As a result,this work provides experimental evidents for using electrochromic peroperties of WO3 thin films within the solar spectrum more effectively.