直流磁控溅射法制备GZO薄膜及其结构和光电性能的研究

为了提高GZO薄膜性能的稳定性,在溅射温度为室温、气压为0.2 Pa、靶基距为100 mm等工艺条件下,利用直流磁控溅射法在氧化铝基底上沉积超厚型的镓掺杂氧化锌(GZO)薄膜,并探究不同溅射功率对GZO薄膜的表面生长方式、内部晶体取向和光电性能的影响。利用X射线衍射仪、四探针、原子力显微镜等仪器对制备的薄膜进行表征,结果发现随着溅射功率的增大,GZO薄膜晶胞的生长方向由径向生长变为横向生长;薄膜内的晶体结构的衍射峰先增强后降低;薄膜在可见光范围内的平均透光率出现先增大后减小,最后再次增加的趋势。GZO薄膜样品的方块电阻随功率的增加逐渐呈现出下降的趋势,当溅射功率为250 W时,薄膜的方块电阻最低,最低值为18Ω/□。当溅射功率为180 W时,薄膜的择优取向衍射峰峰值达到最大,薄膜的晶胞生长饱满并且结晶性能良好,薄膜表面致密性平整;GZO薄膜的平均透光率在可见光波段范围内达到最高并且接近95%,薄膜的方块电阻为34Ω/□。

Growth and Characterization of DC Magnetron Sputtered GZO Films

The ultra-thick gallium-doped zinc oxide(GZO) films were deposited at room temperature by DC magnetron sputtering of a lab-made GZO target on alumina crystals substrate to improve the stability of GZO film properties. The effects of different sputtering power of GZO films were investigated while the argon flow rate was 40sccm, the sputtering pressure was 0.2 Pa, the target distance was 100 mm and the sputtering time was 30 minutes.The GZO films were characterized with X-ray diffraction, four –probe tester, atomic force microscope and ultraviolet visible near infrared spectroscopy. The results show that the grain size of the GZO film gradually increases and the growth direction of the unit cell changes from radial growth to lateral growth with the increase in sputtering power. When the sputtering power increases, the average light transmittance of the film in the visible light range increases first, then decreases, and finally increases again. The sheet resistance of the GZO film samples gradually shows a downward trend with the increase of power. When the sputtering power is 250 W that the minimum sheet resistance of the film is 18 Ω/□. In the case of the sputtering power being 180 W, the preferred orientation diffraction peak of the film reaches the maximum, the unit cell growth of the film is full and the crystalline properties of the film are superior. The average light transmittance of the GZO film reaches the highest in the visible wavelength range and the sheet resistance of the film is 34 Ω/□.