摘要
用PLD法成功制备了一系列高质量的MgZnO薄膜。实验中发现高脉冲能量沉积薄膜的结构和发光特性随基片温度的变化规律与低脉冲能量下的结果不一样:基片在室温时高脉冲能量制备薄膜的XRD峰的半峰全宽比高基片温度时的结果相对更小;AFM显示其颗粒变大,柱状生长突出;PL谱紫峰与绿峰强度比最大,结晶质量反而提高。另一方面,与低脉冲能量时相反,增大氧气压强后高脉冲能量沉积的薄膜XRD半峰全宽变窄。结合实验现象和表征,合理解释了高脉冲能量沉积的机理。室温制备高质量MgZnO薄膜的PLD沉积机理对于以后在柔性衬底上沉积薄膜的研究有重要的参考价值。
A series of high quality MgZnO films are successfully prepared by pulsed laser deposition （PLD） on silicon substrate. It was discovered that with high laser pulse energy deposition the substrate temperature dependence of the structure and luminescence characteristic of the films is not consistent with that under low laser pulse energy. Compared with higher substrate temperature, it is abnormal that the film deposited at room temperature with high laser pulse energy exhibits narrower full width at half maximum （FWHM） of X-ray diffraction （XRD）, bigger grain size and roughness of root mean square （RMS） by atomic force microscopy （AFM）. Moreover, the photoluminescence （PL） spectra show that the intensity of ultraviolet peak was enhanced remarkably and the ratio of ultraviolet peak to green peak is the largest when the film was deposited at room temperature. It can be concluded that the crystal quality of the film deposited with high laser pulse energy at room temperature is better than that of the film deposited at higher temperature. The growth of MgZnO film consists of plane and column direction, which is the preferred orientation because of lowest surface energy. There is strike of plasma plume against the film during high laser pulse energy deposition, which would result in more particles deviation from film with the increase of substrate temperature. However, even at room temperature the particles directly deposited on substrate have enough residual energy due to high laser pulse energy to form high quality film. The FWHM of XRD of the film deposited with high laser pulse energy decreases as the oxygen pressure increases, which is a indirect proof that the enhanced oxygen pressure would weaken the strike of plasma plume against the film. Our work would be of great benefit to the research of growth high quality MgZnO films on flexible substrate at low temperature.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2009年第3期344-350,共7页
Chinese Journal of Luminescence
基金
国家自然科学基金(50872129,60806028)
合肥工业大学博士专项基金资助项目
