The Ferreira and Roger groups at UIUC create novel nanomanufacturing techniques. Recently they have demonstrated a new mode of transfer printing and prototyped an automated transfer printing machine. This process, called Laser Micro-Transfer Printing, enables microassembly of prefabricated structures. Further, this set-up allows for pick-and-place assembly of 3-D heterogeneous microstructures of electronic devices on (flexible) substrates.
Our involvement in this research is the creation of a micromechanical model, which demonstrates the process is driven by a thermomechanical delamination of the printing chip on the substrate, rather than ablation caused by the laser. Hence, we used a finite thickness correction of the Stoney formula to show that the thermal mismatch created between the substrate and chip provides sufficient strain energy density to drive the delamination necessary for placement of the chip.
Project Sponsors: The National Science Foundation
Saeidpourazar R, Li R, Li Y, Sangid MD, Lü C, Huang Y, Rogers JA, Ferreira PM, “Laser-driven non-contact transfer printing of prefabricated silicon microstructures,” To appear in Journal of Microelectromechanical Systems (2012).
Saeidpourazar R, Sangid MD, Rogers JA, Ferreira PM, “A prototype printer for laser driven micro-transfer printing,” Proceedings of NAMRI/SME, North American Manufacturing Research Institution/Society of Manufacturing Engineers, Vol. 40, South Bend, Indiana, June 4-8, 2012.