Cu0, Cu + , and Cu2 from excimer-ablated copper
Abstract
Bulk copper is laser etched with 193- and 351-nm excimer radiation. The transition from the thermal to the plasma etch region is studied by measuring the densities and kinetic energies of three copper species (Cu0, Cu+, and Cu2 ) in the etch plume. A unique laser-induced fluorescence experiment allows these three species to be followed essentially simultaneously as a function of fluence. Three separate types of etching behavior are clearly evident (even within the small fluence range of ∼1-12.5 J/cm2 ); i.e., thermal vaporization of Cu, multiphoton ionization of the Cu vapor, and electron-atom collision-induced ionization (breakdown) and dissociation (of Cu2 ).
- Publication:
-
Journal of Applied Physics
- Pub Date:
- February 1991
- DOI:
- 10.1063/1.347218
- Bibcode:
- 1991JAP....69.1721D