High-Energy Sputtering

Sputtering ratios for copper have been determined in the energy ranges 5–40 kev for bombardment by Ar+, He+, and D+. Argon values range from 6.48 at 5 kev to 9.25 at 27.5 kev, deuterium from 0.048 at 10 kev to 0.023 at 44 kev, and helium from 0.23 at 15 kev to 0.75 at 40 kev. Preliminary data are included for 30-kev sputtering of copper by H+(0.011), D+(0.03), He+(0.13), N+(5.28), Ne+(3.61), Ar+(9.02), CU+(9.60), Kr+(15.15), and U+(20.9). Also included are sputtering ratios at 30 kev for Ar+ on Ta(2.7), Mo(3.31), and Al(2.38). Most of these data are the result of a single measurement, and require further verification. A definite pressure dependence of the sputtering ratio for Ar+ on Cu was found in the range of 0.04 to 0.08 μ.