Surface conductivity modification of ceramics with laser radiation

Laser-assisted processes that enable the direct modification of the surface conductivity of dielectric ceramics by cw- and pulsed-laser irradiation ar e presented: a method for fabrication of conductive structures on Al2O3 wit h CO2 laser irradiation (lambda = 10.6 mu m, cw) is developed, and the feas ibility is proved for Al2O3 of a different purity. A corresponding procedur e for AlN with excimer laser irradiation (lambda = 248 nm, tau = 25 ns) is systematically examined, concerning its dependence on the processing variab les. Zn order to characterize the modification, the laser-treated specimens are analysed with respect to electrical resistivity (by four-point- and tw o-point-probe techniques), chemical composition [Auger-electron (AES), X-ra y-photoelectron spectroscopy(XPS) and electron beam microprobe analysis (EB MA)], structure (micro-Raman spectroscopy) and morphology (microscopy). (C) 1999 Elsevier Science S.A. All rights reserved.