Diagnostics by optical absorption of sputtered atom density in magnetron discharges

Abstract

Densities of sputtered atoms in Ar rf magnetron discharges have been measured by optical absorption. The resonant and self-absorption methods have been used. The first one has given Al and Mg atom densities with an uncertainty of 40% and the second one the order of magnitude of Si atom densities. The Al atom densities are strongly decreasing from 93.7% Al alloy target: (1–5)×1011 cm−3–10.3% Al aluminosilicate glass: (1–2)×109 cm−3. The Si atom density is in the range (3–9)×1010 cm−3 in the aluminosilicate glasses. The Al and Si sputtered atom densities follow the sputtering yields of Al metal and Al, Si oxide targets.