硅纳米晶体的低温共晶合金化制作及其表征

Fabrication of Silicon Nanocrystals by Low Temperature Eutectic Alloying and Their Characterization

利用Au/Sb和Au/Si共晶点温度较低的特点,通过在~400℃合金化的方法,在硅片表面实现了掺Sb纳米晶体的制作。扫描电子显微镜观察到了Au/Si合金化反应形成的倒金字塔形蚀坑以及纳米结构的存在,拉曼散射光谱证实这些结构主要是纳米尺度的晶体,二次离子质谱表明Sb在Si中的掺杂浓度大于2×10^(18) cm^(-3),超过了Sb在体晶硅中的固溶度。该纳米晶体的制作方法简单易行,热预算较低,和其他微纳器件制作工艺的兼容性较好。

Taking advantage of the eutectic points of Au/Sb and Au/Si at low temperatures, silicon nanocrystals doped with Sb atoms are fabricated on the surface of silicon wafers after an alloying reaction around 400℃. Scanning electron microscopy demonstrates that there ex- ist craters in the shape of an inverted pyramid and large amount of nanostructures inside cra- ters on the wafer surface due to Au/Si alloying reactions. Raman scattering spectroscopy ver- ifies that these nanograins largely possess a crystal-like lattice structure. Secondary ion mass spectroscopy reveals that the doping concentration of Sb in Si exceeds 2）K 1018 cm 3, surpass- ing the solid solubility of Sb in the bulk silicon crystal. This growth method is easy to imple- ment with a low thermal budget, which potentially provides it the good compatibility with other micro/nano fabrication processes.