Metallic etching by high power Nd : yttrium-aluminum-garnet pulsed laser irradiation

A Nd:yttrium-aluminum-garnet pulsed laser, with 1064 nm wavelength, 9 ns pu lse width, and 0.9 J maximum pulse energy, is employed to irradiate in vacu um different metal targets (Al, Ti, Ni, Cu, Ta, W, Au, and Pb). In order to measure the erosion thresholds, the etching rates, and the chemical yields , a mass quadrupole spectrometer is interfaced to the vacuum chamber. Etchi ng process shows a threshold, which ranges between 0.1 and 1.6 J/cm(2) for lead and tungsten, respectively. Etching rates range between 0.3 and 10 mug /pulse for copper and lead, respectively. The irradiation produces chemical yields ranging between 0.04 and 0.6 atoms/100 eV for copper and lead, resp ectively. A simple theoretical approach is presented to justify obtained re sults. The objective of collected data concerns the possibility to use ejec ted atoms, neutral and ionized, in an electron cyclotron resonance ion sour ce, in order to provide high current, multiply charge ion beams. (C) 2000 A merican Institute of Physics. [S0034-6748(00)02609-5].