VUV radiation flux from argon DC magnetron plasma

Abstract

Vacuum ultraviolet (VUV) flux of argon plasma radiation in a DC magnetron discharge with a plane circular titanium cathode is measured. It is found that the intensity of VUV radiation, mainly indicated by the resonance lines of argon atoms at 104.8 and 106.7 nm and ions at 92 and 93.2 nm, is proportional to the discharge current and decreases with pressure. Following the results of the measurements, a numerical model of resonance radiation transport is developed to determine the VUV flux to the substrate placed near the sputtering cathode where direct measurements are impossible due to the fast contamination of the detector by sputtered atoms. In the case of a substrate located 10 cm opposite the cathode surface, the upper limit of estimated VUV flux is of the order of 1015 photons cm−2 s−1 at a coating deposition rate of 1.5 nm s−1 for 2 and 12 mTorr gas pressures. Based on the measurements, the damage to a porous low-k dielectric by VUV radiation during the deposition of barrier layers in the DC magnetron discharge is first estimated.

Damage to OSG low‐k films during IPVD deposition of the Ta barrier layer

“…[24] All these lines have an energy higher than the bandgap of SiO 2 and OSG materials. The VUV flux of an argon direct current (DC) magnetron discharge plasma was measured by Pal et al, [25] and the flux was proportional to the discharge current and decreased with pressure. In the experiments of Boffard et al [26,27] it is shown that the VUV radiation flux in Ar ICP discharge depends nonmonotonically on the gas pressure, reaching maximum values at pressures near 10 mTorr in the case of argon.…”

Review on vacuum ultraviolet generation in low‐pressure plasmas

“…A typical problem in magnetron discharge is also the presence of sputtered atoms of cathode material that can contaminate the detector (VUV photodiode) surface. Pal et al [ 33 ] used a fluorescence detector of sodium salicylate to measure the VUV fluxes from argon plasma of DC magnetron discharge far from the substrate, and they estimated the VUV flux on the substrate located near the sputtering cathode using a numerical model of resonance radiation transport. The discharge current varied from 0.3 to 2 A, and discharge voltage from 324 to 437 V for the pressure of 2 mTorr, and from 281 to 364 V for 12 mTorr.…”

“…Pal et al [33] X Iglesias et al [34] X Es-sebbar et al [35] X X Iglesias et al [36] X X Proshina et al [37] X Fantz et al [38] X X X Tigrine et al [39] X X Zotovich et al [40] X X Es-sebbar et al [41] Relative intensities X Rakhimova et al [42] X Boffard et al [43] X X X Zaima et al [44] Lee et al [45] Relative intensities X X Pargon et al [46] X Jinnai et al [47] X X Titus et al [48] X X X X Woodworth et al [49] X Barton et al [50] X X Abbreviation: VUV, vacuum ultraviolet.…”

“…NaSal + spectrometer Ar + (92 and 93.2 nm), atomic lines are reabsorbed HiPIMS on Al Ar 0.5 Pa 35,000 600 Es-sebbar et al [35] 7. 33 Iglesias et al [36] For pure Ar: 18 for λ < 112 (Ar) Fantz et al [38] In H Tigrine et al [39] For example, 4 @1. Zotovich et al [40] Pure Ar:…”

“…Summary of the key experimental parameters and observations reported by different authorsPal et al[33] …”