Versatile Method of Submicroparticle Pattern Formation Using Self-Assembly and Two-Step Transfer

We propose a method of submicroparticle pattern formation with high productivity, flexibility, and accuracy. The proposed process is composed of template-assisted self-assembly for particle self-assembly and a subsequent two-step transfer of the assembled particles. Optimization of the process parameters was performed by carrying out experiments to evaluate the effects of the parameters on the yields of each process. Polystyrene particles that are 500 nm in diameter were used, and a silicon wafer was used as a target substrate in the experiments that are described in this paper. In the self-assembly process, 70% of the pattern was successfully self-assembled on a silicon template substrate. In the first transfer step, a transfer yield of 79% was obtained with a self-assembled-monolayer-coated polydimethylsiloxane carrier substrate. In the second transfer step, a transfer temperature of 115 provided the maximum transfer yield of 85%. The overall process yield of 48% was achieved by the optimized process parameters, and it was successfully demonstrated that the proposed method can fabricate any submicroparticle pattern.