【作者】 何永；

【导师】 周建；

【作者基本信息】 武汉理工大学 ， 光电子及信息材料， 2007， 硕士

【摘要】 随着信息时代的到来，人们对短波长发光器件的需求日益增长，因此人们对宽禁带直接带隙半导体的研究产生了极大的兴趣。氧化锌(ZnO)是一种宽禁带直接带隙(室温下3.37eV)Ⅱ-Ⅵ族化合物半导体材料，室温下激子束缚能60meV，理论上可实现室温下的紫外受激辐射，在紫外发射器件、紫外激光器件等领域具有广阔的应用前景。ZnO薄膜的制作方法很多，溅射法、真空蒸镀、分子束外延、脉冲激光沉积、化学气相沉积、原子层外延、喷雾热分解、溶胶凝胶、锌膜氧化法等。脉冲激光沉积是近年来发展起来的先进的薄膜生长技术，与其他方法相比，脉冲激光沉积法对获得高质量的氧化物薄膜更加有效，因为它具有简单的结构且操作方便，可以通过调节激光能量、激光频率等来控制薄膜的原子层厚度。脉冲激光沉积ZnO薄膜是在高真空背景下用高能激光烧蚀ZnO靶材生成蒸发物沉积在加热衬底上生长晶体薄膜。本文用脉冲激光沉积方法以ZnO陶瓷为靶材，在Si(111)衬底上生长ZnO薄膜，讨论了氧分压、衬底温度、脉冲能量、退火等条件对ZnO薄膜特性的影响；用X射线衍射(XRD)对薄膜的结晶质量进行了分析；用扫描电子显微镜(SEM)对薄膜的表面形貌进行了表征；荧光光致发光谱(PL)对薄膜的发光特性进行了研究，用椭偏膜厚仪对薄膜的膜厚进行了测量。通过对ZnO薄膜的结构和发光特性的研究，分析了生长参数对薄膜特性的影响，找到了生长薄膜的优化条件，得到了高度c轴(002)取向的结晶质量较高的ZnO薄膜。更多还原

【Abstract】 With the fast developing information technology, wide band semiconductors attract much more attention because of the needs of short wavelength devices. ZnO is an II-VI compound wide-band-gap (3.37eV) semiconductor with a large exciton binding energy of 60 meV at room temperature. Theoretically, it can realize stimulated UV emission at RT, which makes it a promising material for using in ultraviolet light-emitting and laser diodes.There are many growth methods for ZnO films such as sputtering, vacuum vaporization, molecular beam epitaxy, pulsed laser deposition, chemical vapor deposition, atom layer epitaxy, spay pyrolysis, thermal oxidation and sol-gel. Pulsed laser deposition is a newly developed films growth technique which can fabricate high-quality films compared with other techniques, because of its advantage of simple hardware, atomic-layer control obtained by adjusting the laser energy density and repetition rate. In this technique, high density laser ablates the ZnO ceramic target and produces ZnO plume depositing on heated substrate in high vacuum background.In this paper, ZnO films were prepared on Si (111) substrates at various oxygen pressures, substrate temperatures and pulse energy, and then annealing was conduct. The films were examined by X-ray diffraction (XRD), scan electron microscopy (SEM), photoluminescence spectra (PL) and ellipsometry. Through the research of the structural and optical properties of ZnO films, effects of deposition parameters and optimized parameters for growing ZnO films were obtained. The results suggested that high quality ZnO films with highly c-axis oriented can be prepared by PLD.更多还原