Large scale microcomponents assembly using an external magnetic array

Abstract

Assembly of 2500 microcomponents has been accomplished in 5 min with assembly yield of 97% by combining magnetic force, shape recognition, and vibration. The host substrate has been patterned with physical cavities having the shape of the target chip and positioned on top of a master substrate which is an 8 in. wafer having array of magnets embedded in it. The chip has been modified by depositing a soft magnetic film (CoNiP) on its back side. By the competition between the magnetic force and the mechanical force, microcomponents have been assembled with their active side facing up. © 2007 American Institute of Physics.