Electrostatic actuated strain engineering in monolithically integrated VLS grown silicon nanowires
Electrostatic actuated strain engineering in monolithically integrated VLS grown silicon nanowires
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DOI：
10.1088/0957-4484/25/45/455705
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发表时间：
2014-10
期刊：
影响因子：
3.5
通讯作者：
S. Wagesreither;E. Bertagnolli;S. Kawase;Y. Isono;A. Lugstein
中科院分区：
文献类型：
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作者：
S. Wagesreither;E. Bertagnolli;S. Kawase;Y. Isono;A. Lugstein
在本文中，我们展示了制造和应用的静电驱动拉伸应变测试（EATEST）设备，使应变工程在个别悬挂纳米线（NW）。与先前报道的方法相反，这种特殊的设置保证了施加纯单轴拉伸应变，而没有应力的剪切分量，同时例如测量NW的电阻变化。为了证明这种方法的潜力，我们研究了约3 μm长和100 nm厚的SiNW的压阻率，但以同样的方式，人们可以考虑将这种器件应用于其他几何形状，Si以外的其他材料以及使用其他表征技术。因此，单晶硅纳米线单片集成在梳状驱动驱动MEMS器件的基础上的绝缘体上硅（SOI）晶片使用的汽-液-固（VLS）生长技术。通过用扫描电子显微镜（SEM）精确测量NW伸长率来验证应变值。此外，我们采用共焦μ-拉曼显微镜在原位，高空间分辨率测量的应变在个别硅纳米线在电气特性。观察到一个巨大的压阻效应，导致电导率增加了5倍，为3%的单轴应变硅纳米线。由于EATEST方法可以很容易地集成到现有的Si技术平台中，因此这种架构可以通过利用应变自由度为新一代非传统器件铺平道路。
In this paper we demonstrate the fabrication and application of an electrostatic actuated tensile straining test (EATEST) device enabling strain engineering in individual suspended nanowires (NWs). Contrary to previously reported approaches, this special setup guarantees the application of pure uniaxial tensile strain with no shear component of the stress while e.g. simultaneously measuring the resistance change of the NW. To demonstrate the potential of this approach we investigated the piezoresistivity of about 3 μm long and 100 nm thick SiNWs but in the same way one can think about the application of such a device on other geometries, other materials beyond Si as well as the use of other characterization techniques beyond electrical measurements. Therefore single-crystal SiNWs were monolithically integrated in a comb drive actuated MEMS device based on a silicon-on-insulator (SOI) wafer using the vapor–liquid–solid (VLS) growth technique. Strain values were verified by a precise measurement of the NW elongation with scanning electron microscopy (SEM). Further we employed confocal μ-Raman microscopy for in situ, high spatial resolution measurements of the strain in individual SiNWs during electrical characterization. A giant piezoresistive effect was observed, resulting in a fivefold increase in conductivity for 3% uniaxially strained SiNWs. As the EATEST approach can be easily integrated into an existing Si technology platform this architecture may pave the way toward a new generation of nonconventional devices by leveraging the strain degree of freedom.