Si纳米量子点的LPCVD自组织化形成及其生长机理研究

采用低压化学汽相沉积(LPCVD)方法，依靠纯SiH₄气体分子的表面热分解反应， 在由Si—O—Si键和由Si—OH键终端的两种SiO₂表面上，自组织生长了Si纳米量子点. 实 验研究了所形成的Si纳米量子点密度随SiO₂表面的反应活性位置数、沉积温度以及反应气 压的变化关系. 依据LPCVD的表面热力学过程，定性地分析了Si纳米量子点的形成机理.研究结果对具有密度分布均匀和晶粒尺寸可控的Si纳米量子点的自组织生长，以及Si基新型量子电子器关键词：Si纳米量子点LPCVD自组织化形成生长机理

Formation of self-assembly and the mechanism of Si nanoquantum dots prepared by low pressure chemical vapor deposition

Si nanoquantum dots have been formed by self-assembled growth on the both Si—O—Si and Si—OH bonds terminated SiO₂ surfaces using the low-pressur e chemical vapor deposition (LPCVD) and surface thermal decomposition of pure SiH_{4< /sub> gas. We have experimentally studied the variation of Si dot density with Si—OH bonds density, deposition temperature and SiH4 pressure, and analyzed qu alitatively the formation mechanism of the Si nanoquantum dots based on LPCVD surface thermal dynamics principle. The results are very important for the control of the density and size of Si nanoquantum dots, and have potential applications in the new quantum devices.}