LASER-INDUCED FLUORESCENCE OBSERVATION OF IN-ATOMS PRODUCED BY DC REACTIVE SPUTTERING OF INDIUM-TIN-OXIDE TARGET

Spatial density profiles of sputtered In-atoms in a de glow discharge with an indium-tin-oxide (ITO) cathode were measured by laser-induced fluorescence (LIF) spectroscopy. The absolute density of In-atoms was obtained by calibrating the LIF signal with the Rayleigh scattering signal for Ar. The spatial density profile of In-atoms had a peak at a certain distance from the cathode, and this peak density was about 10(11) cm(-3) for pure Ar de discharge at 0.2 Torr and 0.6 Wcm(-2) The behavior of spatial profiles of the absolute In-density was investigated as a function of de discharge power, total pressure (Ar+O-2), and O-2 partial pressure. Addition of a small amount of O-2 caused a drastic change in both the absolute In-density and its spatial distribution. From these observations, the reactive sputtering mechanism in a de glow discharge is discussed.