title: Rapid, controllable fabrication of regular complex microarchitectures by capillary assembly of micropillars and their application in selectively trapping/releasing microparticles.
abstract: A simple strategy to realize new controllable 3D microstructures and a novel method to reversibly trapping and releasing microparticles are reported. This technique controls the height, shape, width, and arrangement of pillar arrays and realizes a series of special microstructures from 2-pillar-cell to 12 cell arrays, S-shape, chain-shape and triangle 3-cell arrays by a combined top down/bottom up method: laser interference lithography and capillary force-induced assembly. Due to the inherent features of this method, the whole time is less than 3 min and the fabricated area determined by the size of the laser beam can reach as much as 1 cm(2) , which shows this method is very simple, rapid, and high-throughput. It is further demonstrated that the 'mechanical hand'-like 4-cell arrays could be used to selectively trap/release microparticles with different sizes, e.g., 1.5, 2, or 3.5 μm, which are controlled by the period of the microstructures from 2.5 to 4 μm, and 6 μm. Finally, the 'mechanical hand'-like 4-cell arrays are integrated into 100 μm-width microfluidic channels prepared by ultraviolet photolithography, which shows that this technique is compatible with conventional microfabrication methods for on-chip applications.
authors.affiliation: State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, PR China.
authors.forename: Dong
authors.initials: D
authors.lastname: Wu
authors.forename: Si-Zhu
authors.initials: SZ
authors.lastname: Wu
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhao
authors.forename: Jia
authors.initials: J
authors.lastname: Yao
authors.forename: Jiang-Nan
authors.initials: JN
authors.lastname: Wang
authors.forename: Qi-Dai
authors.initials: QD
authors.lastname: Chen
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Sun