采用离子束溅射技术，在生长了Si缓冲层的硅晶片上制备了一系列Ge量子点样品.借助原子力显微镜(AFM)和Raman光谱等测试手段研究了Ge/Si量子点生长密度、尺寸及排列均匀性的演变规律.结果表明，改变Si缓冲层厚度及其生长方式，可以有效控制量子点的尺寸、均匀性和密度.随缓冲层厚度增大，量子点密度先增大后减小，停顿生长有利于提高缓冲层结晶性，从而提高量子点的密度，可以达到1.9×1010 cm-2.还研究了Si缓冲层在Ge量子点生长过程中的作用，并提出了量子点的生长模型.

A series of Ge quantum dot samples were grown by ion beam sputtering on Si (100) substrates with a Si buffer layer. The evolution of the topography and dimension of Ge/Si quantum dot were characterized using AFM and Raman spectra. The results show that the density of the quantum dots increased to a maximum and then decreased with the thickness of Si buffer layers, the maximum is up to 1.9×1010 cm-2 due to the influence of the thickness and growth patterns of Si buffer layers. Growth interruption is beneficial to improve the crystallization of Si buffer layer and the density of the quantum dot. The effects of Si buffer layers which manipulate the growth and shape of the Ge quantum dots are discussed in details. In addition, a growth model of the quantum dots is proposed.