High-accuracy positioning of microchips on patterns with jagged edges using hybrid microassembly

This paper studies the accuracy of positioning 200μm × 200μm SU-8 chips on patterns with jagged edges using hybrid microassembly technique. This hybrid microassembly technique combines both the robotic pick-and-place and the droplet self-assembly technique, where the robotic technique is used for coarse positioning and the droplet self-assembly technique is applied to achieve the high-accuracy positioning. To study the positioning accuracy on patterns with jagged edges, patterns with regular and random jaggedness of 1 μm-8 μm have been designed and fabricated. An image based analysis method is used to determine the positioning accuracy after droplet self-assembly is achieved. The results show that the edge jaggedness has less significant effect on the positioning accuracy than we expected. The positioning accuracy decreases as the amplitude of the edge jaggedness increases. However, high positioning accuracy of 2μm can still be achieved even with the edge jaggedness of 8μm.