In-process measurement of micro-contact printing

Abstract

In micro contact printing, a polymer stamp with sub micron features is use to pattern a substrate. Micro contact printing has many applications including micro machined circuits and miniaturized biological test kits. Success in printing has been achieved in limited batch processing of plate to plate printing. The physics and chemistry of stamp contact and ink transfer has been studied. To make micro contact printing economically viable developments have been made to advance a roll to roll configuration. Roll to roll processing offers the potential of high volume low cost micro manufacturing similar to the high volume achieved by roll to roll processing for traditional lithography. Roll to roll micro contact printers have been built at the lab scale. The process has been demonstrate to have the potential for rapid high volume production. The current limitation is in the quality of the print. Features on the stamp are printed with defects such as breaks or undesired patterning. The source of failure lies with the contact of the stamp; the stamp either breaking contact or collapsing to allow areas outside of the features to make contact. A barrier to better understanding and controlling contact during the printing process has been a lack of in-process measurement. This thesis examines the use of a new optical set-up to monitor stamp contact in-process on a lab level roll to roll micro contact printer. Image based measures of stamp contact quality are presented.