Mechanics and scaling of thin part assembly at a fluidic interface

This paper presents an experimental and theoretical study of a high yield self-assembly process with a programmable template. An analysis of the fluidic assembly method at an air-water interface is presented with an emphasis on the combined effect of a substrate tilting angle and part size. For 1 x 1, 3 x 3 and 5 x 5 mm(2) parts with 100 mu m thickness, the maximum substrate tilting angles are experimentally determined and the surface tension induced torques are derived from the developed model. The result indicates that there is a limit on the lateral size of the parts that can be assembled when we use just one substrate tilting angle. Based on our analysis, we also propose a novel method that is capable of assembling parts of higher lateral dimensions using parametric changes in the substrate tilting angle.