New approach to laser direct writing active and passive mesoscopic circuit elements

We have combined some of the major positive advantages of laser-induced forward transfer (LIFT) and matrix-assisted pulsed laser evaporation (MAPLE), to produce a novel excimer laser driven direct writing technique which has demonstrated the deposition in air and at room temperature and with sub-10 mu m resolution of active and passive prototype circuit elements on planar and nonplanar substrates. We have termed this technique MAPLE DW (matrix-assisted pulsed laser evaporation direct write) and present its historical evolution from pulsed laser deposition. This paper describes the simplistic approach to carry out MAPLE DW, gives experimental conditions, and physical characterization results for the deposition of NiCr thin film resistors, Au conducting lines, and multilayer depositions of Au conductors and BaTiO3 dielectrics to produce prototype capacitors. In general, the electrical properties of the materials deposited (conductivity, dielectric constant, and loss tangent) are comparable or superior to those produced by other commonly used industrial processes such as screen printing. The mechanism of the MAPLE DW process, especially the novel aspects making it a powerful approach for direct writing all classes of materials (metals, oxide ceramics, polymers and composites), is also described. (C) 2000 Published by Elsevier Science B.V. All rights reserved.