Fig. 1. AFM image of the trench-patterned Si substrate before (a) and after (b) the growth of Si buffer layer, insets are the zoom-in images of one end of a trench before and after the Si buffer layer, respectively.生长硅缓冲层前(a)和生长硅缓冲层后(b)硅周期性凹槽结构的表面AFM图, 插图分别为生长硅缓冲层前后凹槽末端的放大图

Fig. 2. (a) AFM image of ordered GeSi wires on trench patterned substrate; (b) AFM image of zoom-in individual GeSi nanowire; (c) AFM linescan along the cross-section of a GeSi nanowire. Inset scale bar: 500 nm.(a)硅衬底上有序锗硅纳米线的AFM图; (b)单根锗硅纳米线的AFM图; (c)单根纳米线的表面线扫描图, 图中标尺均为500 nm

Fig. 3. AFM images of the trench-patterned samples with 4 nm Si₆₇Ge₃₃ film after 1 h annealing at different temperatures: (a) 450 ℃; (b) 500 ℃; (c) 510 ℃; (d) 520 ℃; (e) 530 ℃; (f) 550 ℃. 在硅凹槽结构图形衬底上沉积4 nm的Si₆₇G₃₃薄膜, 然后在不同温度退火后得到的样品表面AFM图　(a) 450 ℃; (b) 500 ℃; (c) 510 ℃; (d) 520 ℃; (e) 530 ℃; (f) 550 ℃

Fig. 4. The influence of Ge concentration on the formation of SiGe wires when the thickness of SiGe film is fixed: (a) Si₆₈G₃₂; (b) Si₆₆G₃₄; (c) Si₆₃G₃₇. 固定薄膜厚度时, 锗的含量比例对纳米线结构的影响　(a) Si₆₈G₃₂; (b) Si₆₆G₃₄; (c) Si₆₃G₃₇

Fig. 5. AFM images of GeSi wires on trench-patterned Si (001) with different pattern periods: (a) period of 2 µm; (b) period of 500 nm.不同周期图形衬底上锗硅纳米线的表面AFM图　(a)周期为2 µm; (b)周期为500 nm