<title>AlN surface modification by UV laser radiation</title>

Abstract

One-step process surface modifications of AlN ceramics have been obtained by UV laser irradiation ((lambda) equals 248 nm). Results concerning some physical and chemical property modifications of AlN surface are here reported. Characterizations by optical microscopy, energy dispersive spectroscopy and grazing X-ray diffraction (XRD) have lead to show the `metallization' process induced by the laser irradiation under particular conditions, due to the AlN decomposition and the Al metal formation. Grazing XRD has clearly shown the Al presence into the laser impacted zones. Electrical resistance measurements have confirmed this surface `metallization' by the highlighting of a very sharp transition zone between the insulator substrate (R > 20 M(Omega) ) and an Al-rich conductive path (R approximately equals 10 - 20 (Omega) ) on only a few 10 micrometers . These last measurements have allowed to easily define efficient laser conditions regarding to this `metallization' process: about 20 laser pulses of 20 ns under a fluence of about 2.0 J/cm2 seems to lead to an homogeneous conductive path on insulator AlN substrate.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.