Huan Hu, Hoe Joon Kim, et al.
Micromachines
We report a novel methodology for fabricating a sub-micron spherical atomic force microscope (AFM) tip controllably - a silicon sub-micron sphere atop microcantilevers, which is desired for precise nanoscale tribology measurements, biological studies, and colloid science. Silicon sub-micron spheres are fabricated through swelling of single-crystal silicon with proper high-energy helium ion dosing, a traditionally undesired phenomenon known in helium ion microscopy. Silicon sub-micron spheres with diameters from 100 nm to 1 μm are demonstrated, and the placement of silicon sub-micron spheres can be as accurate as 10 nm or even below. This AFM tip demonstrates robust measurements during friction tests on graphene/silicon oxide substrates for more than 10 »000 cycles. This AFM tip overcomes a critical challenge of reducing the size of spherical AFM tips from the micrometer scale to the sub-micron scale and is promising in cross-scale mechanics studies, nanotribology, colloid science, and biology.
Huan Hu, Hoe Joon Kim, et al.
Micromachines
Katsuyuki Sakuma, Huan Hu, et al.
IFETC 2018
Adam Pyzyna, Hsinyu Tsai, et al.
IITC 2017
Huan Hu, Changjin Huang, et al.
Extreme Mechanics Letters