Transfer printing: An approach for massively parallel assembly of microscale devices

Transfer printing is a new technique that enables the massively parallel assembly of high performance semiconductor devices onto virtually any substrate material, including glass, plastics, metals or other semiconductors. This semiconductor transfer printing technology relies on the use of an elastomeric molded stamp to selectively pick-up devices from a source wafer and then prints the devices onto the target substrate. The key enabling technique is the ability to tune the adhesion between the elastomeric stamp and the semiconductor devices. The transfer process is massively parallel as the stamps are designed to transfer thousands of discrete devices in a single pick-up and print operation. Studies of the process yield indicate that print yields in excess of 99.9% can be achieved. In addition, experiments show that the chips can be printed with placement accuracy better than +/- 5 mu m.