COMPARISON OF MAGNETRON SPUTTER-DEPOSITION CONDITIONS IN NEON, ARGON,KRYPTON, AND XENON DISCHARGES

The ion and deposition fluxes to the substrate during sputtering of a vanadium target in neon, argon, krypton, and xenon discharges were mea sured as a function of the discharge power and gas pressure. The measu rements of the deposition fluxes were also compared with calculations obtained using an analytical model for transport of the sputtered spec ies through the gas discharge. The calculation takes into account both the ballistic and thermal components of the deposition flux. Overall, a good agreement between the calculated and the experimentally measur ed values was obtained. The results show that, at a constant discharge current, the vanadium flux at the substrate position is a strong func tion of both pressure and the type of inert gas used' The ion flux, on the other hand, remains relatively constant as the gas and pressure a re changed. This implies that the ion-to-neutral arrival rate ratio wa s dominated by changes in the neutral deposition flux and it was found to increase with pressure, remain relatively constant with power at l ow pressures, and decrease with power at high pressures. By increasing the field strength of the outer pole in the magnetron source (unbalan ced magnetron source of type II), the ion flux impinging the substrate was strongly increased for all pressures, while the vanadium depositi on flux remained the same as in the ''balanced'' magnetron configurati on.