Institute of Solid State Electronics, TU-Wien, Floragasse 7, A-1040 Vienna, Austria.
Beilstein J Nanotechnol. 2012;3:564-9. doi: 10.3762/bjnano.3.65. Epub 2012 Jul 31.
Perchlorinated polysilanes were synthesized by polymerization of tetrachlorosilane under cold plasma conditions with hydrogen as a reducing agent. Subsequent selective cleavage of the resulting polymer yielded oligochlorosilanes Si(n)Cl(2) (n) (+2) (n = 2, 3) from which the octachlorotrisilane (n = 3, Cl(8)Si(3), OCTS) was used as a novel precursor for the synthesis of single-crystalline Si nanowires (NW) by the well-established vapor-liquid-solid (VLS) mechanism. By adding doping agents, specifically BBr(3) and PCl(3), we achieved highly p- and n-type doped Si-NWs by means of atmospheric-pressure chemical vapor deposition (APCVD). These as grown NWs were investigated by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as electrical measurements of the NWs integrated in four-terminal and back-gated MOSFET modules. The intrinsic NWs appeared to be highly crystalline, with a preferred growth direction of [111] and a specific resistivity of ρ = 6 kΩ·cm. The doped NWs appeared to be [112] oriented with a specific resistivity of ρ = 198 mΩ·cm for p-type Si-NWs and ρ = 2.7 mΩ·cm for n-doped Si-NWs, revealing excellent dopant activation.
全氯代聚硅烷是在冷等离子体条件下通过四氯化硅聚合反应，以氢气作为还原剂合成的。随后，对所得聚合物进行选择性裂解，得到低聚氯硅烷 Si(n)Cl(2) (n) (+2)（n = 2,3），其中八氯三硅烷（n = 3, Cl(8)Si(3), OCTS）被用作通过成熟的气-液-固（VLS）机制合成单晶 Si 纳米线（NW）的新型前体。通过添加掺杂剂，特别是 BBr(3) 和 PCl(3)，我们通过常压化学气相沉积（APCVD）实现了高度 p 型和 n 型掺杂的 Si-NWs。通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）以及集成在四端和背栅 MOSFET 模块中的 NW 的电测量对这些生长的 NW 进行了研究。本征 NW 表现出高度的结晶性，具有[111]的优先生长方向和ρ = 6 kΩ·cm 的特定电阻率。掺杂 NW 似乎呈[112]取向，p 型 Si-NWs 的特定电阻率为 ρ = 198 mΩ·cm，n 型掺杂 Si-NWs 的特定电阻率为 ρ = 2.7 mΩ·cm，表明掺杂剂的激活效果极好。
