Optimization of Process Parameters for Micropart Capillary Assembly with Precision Positioning

The assembly of microdevices is currently done mainly with the pick and place method. However, this method is slow and expensive for assembly requiring high precision. Thus, the development of a new fast, yet highly precise method of assembly is the focus of current research. Self-assembly in liquid medium, where microdevices spontaneously arrange themselves into more complex systems using capillary forces, has been shown to be a potential candidate for parallel batch assembly with precision positioning. However, studies of how the design and process variables affect the precision of the method have yet to be investigated. The main barrier to achieving the desired precision in the x-y direction is the tilting of parts during the assembly process. In this project, we investigated the effect the volume of adhesive has on tilting and developed a theoretical model for the tilting. Our data show that the magnitude of tilting increases as the volume of adhesive used increases, in accordance with the model. In addition, we studied a method using vertical vibration with a speaker to correct the tilting. Our data show that this method is practical under certain conditions of adhesive coverage on the binding sites. With further investigation, tilting should be able to be corrected consistently.