Lin Yung-Chen, Lu Kuo-Chang, Wu Wen-Wei, Bai Jingwei, Chen Lih J, Tu K N, Huang Yu
Department of Materials Science and Engineering, University of California, Los Angeles 90095-1595, USA.
Nano Lett. 2008 Mar;8(3):913-8. doi: 10.1021/nl073279r. Epub 2008 Feb 12.
We report the formation of PtSi nanowires, PtSi/Si/PtSi nanowire heterostructures, and nanodevices from such heterostructures. Scanning electron microscopy studies show that silicon nanowires can be converted into PtSi nanowires through controlled reactions between lithographically defined platinum pads and silicon nanowires. High-resolution transmission electron microscopy studies show that PtSi/Si/PtSi heterostructure has an atomically sharp interface with epitaxial relationships of Si[110]//PtSi[010] and Si(111)//PtSi(101). Electrical measurements show that the pure PtSi nanowires have low resistivities approximately 28.6 microOmega.cm and high breakdown current densities>1x10(8) A/cm2. Furthermore, using single crystal PtSi/Si/PtSi nanowire heterostructures with atomically sharp interfaces, we have fabricated high-performance nanoscale field-effect transistors from intrinsic silicon nanowires, in which the source and drain contacts are defined by the metallic PtSi nanowire regions, and the gate length is defined by the Si nanowire region. Electrical measurements show nearly perfect p-channel enhancement mode transistor behavior with a normalized transconductance of 0.3 mS/microm, field-effect hole mobility of 168 cm2/V.s, and on/off ratio>10(7), demonstrating the best performing device from intrinsic silicon nanowires.
我们报道了铂硅纳米线、铂硅/硅/铂硅纳米线异质结构以及由这种异质结构构成的纳米器件的形成。扫描电子显微镜研究表明，通过光刻定义的铂垫与硅纳米线之间的可控反应，硅纳米线可以转化为铂硅纳米线。高分辨率透射电子显微镜研究表明，铂硅/硅/铂硅异质结构具有原子级尖锐的界面，其外延关系为Si[110]//PtSi[010]和Si(111)//PtSi(101)。电学测量表明，纯铂硅纳米线具有约28.6微欧·厘米的低电阻率和大于1×10⁸安/平方厘米的高击穿电流密度。此外，利用具有原子级尖锐界面的单晶铂硅/硅/铂硅纳米线异质结构，我们从本征硅纳米线制造了高性能的纳米级场效应晶体管，其中源极和漏极接触由金属铂硅纳米线区域定义，栅极长度由硅纳米线区域定义。电学测量表明，该晶体管具有近乎完美的p沟道增强模式晶体管行为，归一化跨导为0.3毫西门子/微米，场效应空穴迁移率为168平方厘米/伏·秒，开/关比大于10⁷，证明了这是本征硅纳米线性能最佳的器件。
