Lee Hee Kwan, Yu Jae Su
Department of Electronics and Radio Engineering, Institute for Laser Engineering, Kyung Hee University, 1 Seocheon-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do 446-701, Republic of Korea.
J Nanosci Nanotechnol. 2012 Apr;12(4):3123-9. doi: 10.1166/jnn.2012.5827.
We investigated the effect of growth parameters on the structural and optical properties of the ZnO nanostructures (NSs) grown on Au-coated Si substrate by a two-zone thermal chemical vapor deposition. The morphologies of ZnO NSs were controlled by various growth parameters, such as growth temperature, O2 flow rate, and working pressure, for different thicknesses of Au layer. The nanorod-like ZnO NSs were formed at 915 degrees C and the growth of two-dimensional structures, i.e., nanosheets, was enhanced with the increase of growth temperature up to 965 degrees C. It was found that the low working pressure contributed to improvement in vertical alignment and uniformity of ZnO NSs. The Zn/O atomic % ratio, which plays a key role in the growth mechanism of ZnO NSs, was changed by the growth parameters. The Zn/O atomic % ratio was increased with increasing the growth temperature, while it was decreased with increasing the working pressure. Under proper O2 flow rate, the ZnO nanorods with good crystallinity were fabricated with a Zn/O atomic % ratio of -0.9. For various growth parameters, the photoluminescence emission was slightly shifted with the ultraviolet emission related to the near band edge transition.
我们通过两区热化学气相沉积法研究了生长参数对在涂金硅衬底上生长的ZnO纳米结构（NSs）的结构和光学性质的影响。对于不同厚度的金层，通过各种生长参数（如生长温度、O₂流速和工作压力）来控制ZnO NSs的形貌。在915℃时形成了纳米棒状的ZnO NSs，随着生长温度升高至965℃，二维结构（即纳米片）的生长得到增强。发现低工作压力有助于改善ZnO NSs的垂直排列和均匀性。在ZnO NSs的生长机制中起关键作用的Zn/O原子百分比比值会因生长参数而改变。Zn/O原子百分比比值随生长温度的升高而增加，而随工作压力的增加而降低。在适当的O₂流速下，制备出了具有良好结晶性、Zn/O原子百分比比值为-0.9的ZnO纳米棒。对于各种生长参数，光致发光发射与近带边跃迁相关的紫外发射略有偏移。
