单斜氧化铜薄膜的磁控溅射制备及表征

采用磁控溅射, 通过氧氩比的调制在玻璃衬底上沉积了单斜结构的CuO薄膜, 并重点研究了氧氩比对薄膜微结构及光学吸收边的影响。研究表明随着氧氩比的增加, 薄膜逐渐从多相向单相转变, 薄膜表面逐渐趋于光滑和平整, CuO<-111>择优取向逐渐减弱。晶轴上的晶格畸变结果显示氧氩比对晶轴 a, b和 c的影响不尽相同。a, b轴上呈现的压应力均先明显增大然后变得稳定, 而 c轴上则呈现了压应力向拉应力的转变。氧氩比对晶格常数的影响反应了 a, b和 c轴上晶粒生长的各向异性。CuO薄膜为直接带隙半导体, 其1.9 e V附近的光学吸收边随着氧氩比的增加而略微蓝移, 吸收边的蓝移归结于晶粒的量子尺寸效应。

Growth and Property Characterization of Monoclinic CuO Coatings

The monoclinic CuO films were deposited by magnetron sputtering on glass substrate.The effect of the O₂/Ar ratio on the microstructures and optical properties was investigated with X-ray diffraction, scanning electron microscopy and spectrophotometer.The results show that the O₂/Ar ratio had a major impact.To be specific, as the O₂/Ar ratio increased, the poly-to mono-crystalline transition occurred, accompanied by a decrease of the <-111> preferential growth orientation; the CuO coatings, grown in anisotropic manner, became increasingly compact and smooth; the compressive stress along a-and b-axis changed in an increase-leveloff mode, while the compressive stress transited into tensile stress in c-axis; a slight blue-shift of the optical absorption edge near 1.9 e V of the direct-gap CuO semiconductor showed up, possibly because of quantum size effect of CuO grains.