衬底温度对反应磁控溅射W掺杂ZnO薄膜的微观结构及光电性能的影响

Temperature-dependant growth and properties of W-doped ZnO thin films deposited by reactive magnetron sputtering

采用直流脉冲反应磁控溅射方法生长W掺杂ZnO(WZO)透明导电氧化物薄膜并研究了衬底温度对薄膜微观结构、组分、表面形貌以及光电性能的影响.实验结果表明,WZO薄膜具有良好的(002)晶面择优取向,且适当的衬底温度是制备优质WZO薄膜的关键因素.随着衬底温度升高,薄膜表面粗糙度先增大后减小;衬底温度较高时,薄膜的结构致密,结晶质量好,电子迁移率高.当衬底温度为325℃时,WZO薄膜获得最低电阻率9.25×10^(-3)Ω·cm,方块电阻为56.24Ω/□,迁移率为11.8 cm^2 V^(-1)·s^(-1),其在可见光及近红外区域(400—1500 nm)范围的平均透过率达到85.7%.

W-doped ZnO （WZO） thin films for thin film solar cells have been deposited by pulsed direct-current reactive magnetron sput- tering. The microstructures, surface morphologies, optical and electrical properties of WZO thin films are investigated at different substrate temperatures. The experimental results indicate that a proper substrate temperature is the key factor for fabricating high- quality WZO thin films. The surface roughness of WZO thin films increases firstly from 15.65 nm to 37.60 nm, and then decreases from 37.60 nm to 11.07 nm with the increase of substrate temperature. Higher Hall mobility deposited at the higher temperatures is attributed to the compact structure and good crystallization quality. The WZO thin film prepared at the temperature of 325℃ presents excellent optical and electrical properties with an average transmittance of 85.7% in the wavelength range from 400 nm to 1500 nm, a low resistivity of 9.25×10^-3 Ω.cm, a sheet resistance of 56.24 Ω/sq and a high Hall mobility of 11.8 cm2.V-1.s^-1.