Goldsche M, Verbiest G J, Khodkov T, Sonntag J, Driesch N von den, Buca D, Stampfer C
JARA-FIT and 2nd Institute of Physics, RWTH Aachen University, D-52074 Aachen, Germany. Peter Grünberg Institute (PGI-8/9), Forschungszentrum Jülich, D-52425 Jülich, Germany.
Nanotechnology. 2018 Sep 14;29(37):375301. doi: 10.1088/1361-6528/aacdec. Epub 2018 Jun 20.
We report on the fabrication and characterization of an optimized comb-drive actuator design for strain-dependent transport measurements on suspended graphene. We fabricate devices from highly p-doped silicon using deep reactive ion etching with a chromium mask. Crucially, we implement a gold layer to reduce the device resistance from ≈51.6 kΩ to ≈236 Ω at room temperature in order to allow for strain-dependent transport measurements. The graphene is integrated by mechanically transferring it directly onto the actuator using a polymethylmethacrylate membrane. Importantly, the integrated graphene can be nanostructured afterwards to optimize device functionality. The minimum feature size of the structured suspended graphene is 30 nm, which allows for interesting device concepts such as mechanically-tunable nanoconstrictions. Finally, we characterize the fabricated devices by measuring the Raman spectrum as well as the a mechanical resonance frequency of an integrated graphene sheet for different strain values.
我们报告了一种优化的梳状驱动致动器设计的制造与特性，该设计用于对悬浮石墨烯进行应变相关的输运测量。我们使用带有铬掩膜的深反应离子刻蚀技术，从高度p型掺杂的硅制造器件。至关重要的是，我们采用了一层金来将器件在室温下的电阻从约51.6 kΩ降低至约236 Ω，以便能够进行应变相关的输运测量。通过使用聚甲基丙烯酸甲酯膜将石墨烯机械地直接转移到致动器上，从而实现石墨烯的集成。重要的是，之后可以对集成的石墨烯进行纳米结构化处理，以优化器件功能。结构化悬浮石墨烯的最小特征尺寸为30 nm，这使得诸如机械可调纳米缩颈等有趣的器件概念成为可能。最后，我们通过测量拉曼光谱以及针对不同应变值的集成石墨烯片的机械共振频率，来表征所制造的器件。
