Achieving selective assembly with template topography and ultrasonically induced fluid forces.

A site-selective self-assembly technique called templated assembly by selective removal is introduced. Initial experiments demonstrated selective assembly of 1.58 mum microspheres into shape-matched holes in a lithographically defined template. Very high frequency ultrasound selectively removes components from poorly matched holes. The successful demonstration of the technique was supported by detailed understanding and calculation of the kinematics of component removal in the ultrasonic field. The technique is expected to be scalable to smaller component sizes.