Assembly of Topographical Micropatterns with Optoelectronic Tweezers

Abstract Topographical micropatterns (TMPs), or ordered arrays of 3D features on a flat surface, have become important for a wide range of applications. A new optofluidic method based on optoelectronic tweezers to assemble TMPs from suspensions of microparticles in fluid is reported. After assembly, TMPs can be freeze‐dried and then transferred to alternate substrates. 3D simulations are carried out to clarify the experimental results and techniques are developed to evaluate pattern‐transfer fidelity, which is found to be >90% for a wide range of different structures. The optofluidic assembly method described here is facile and accessible, suggesting utility for a wide range of microfabrication and microassembly applications in the future.