Design, fabrication and implementation of a flexure-based micropositioner for Dip Pen Nanolithography

Abstract

Dip Pen Nanolithography (DPN) takes the concept of a quill-tip pen and shrinks it to the nanometer scale. DPN uses a machine to pick up and deposit proteins and liquids in arrays. A problem with the machine however is aligning the pen tip relative to the machine. Currently, it is aligned manually, which is time and labor intensive. It would drastically increase productivity and throughput if a machine was developed that could perform this task accurately and repeatedly. This would also allow quick tool changes for experiments involving multiple DPN processes. The impact of this alignment machine is that it solves problems not only for DPN machines, but also for atomic force microscopes and similar instruments. This thesis is about the design and implementation of this alignment machine. The user would arbitrarily place the pen tip on a ball mount. The ball mount would have three holes that are larger than three balls. The balls are held stationary, while the ball mount can move over it. An overhead camera is used to determine the actual and desired position of the ball mount relative to the balls. Once the ball mount reaches its desired position, the balls are glued in place using UV-cured epoxy. This half of a kinematic coupling would then attach to the other half of a kinematic coupling on the DPN machine. The repeatability of the ball mount holder was tested and has an in-plane 1[sigma] translational repeatability of 15.9 [mu]m and 0.0122 rad. This can be improved and further work is suggested.