National Research Nuclear University MEPh I Department of

National Research Nuclear University «MEPh. I» Department of plasma physics EXPERIMENTS FOR DETERMINATION OF THE ELEMENTAL COMPOSITION AND THICKNESS OF THE AL FILM ON THE W SURFACE Student: Dvornova A. A. Scientific adviser: Sinelnikov D. N. Moscow, 2013

EXPERIMENTAL SCHEME 1 – Duoplasmatron 2 – Separating magnet 3 – Target 4 – Plasma source 5 – Electrostatic energy analyzer 6 – Secondary electron multiplier 7 – Target heater (quartz lamp Р=130 W) 1 2 α Technical details 4 3 7 5 Θ 6 • Energy of the primary ion beam- 0, 5 – 15 ke. V • Energy dispersion ~30 e. V • Typical current of the primary beam~ 5 µА (He+ 5 ke. V) • Target heater (quartz lamp Р=130 W, Тмах ~ 400 С 0) • Working pressure – 7, 5× 10 -7 Torr • Resolution of energy analyzer – 1, 5%, • Scattering angle - 160 • Registration angle - 1, 1 x 10 -3 str • Working gases: H, He, Ar • Plasma temperature and concentration sputtring source T= 5 e. V, n=108 cm 3

SAMPLE PREPARATION Aluminum and tungsten layers were sequentially sputtered on a silicon substrate Sample № 1 Al 10ű 5Å Al 36ű 5Å W 150ű 10Å Roughness: 21 nm The result of measuring the surface by the profilometer Sample № 2 Roughness: 39 nm

ELEMENTAL COMPOSITION O C Al The energy spectrum of negative ions reflected and elastically knocked out from the surface of the sample № 1 bombarded with Ar, 2 ke. V

EXPERIMENTAL RESULTS silicon sample

EXPERIMENTAL RESULTS Sample № 2: 36Å AL 2 O 3 на 150Å W

CONCLUSION • A method for determination of the elemental composition and thickness of the Al film on the W was tested • First calibration experiments with well-known targets were made • Comparison of the experimentally measured energy spectrum with the results of computer modeling was made to determine thickness of the foil • Ion sputtering and heating were applied for cleaning the surface • Experimental energy spectra start looking alike with simulated with CH monolayer on the sample surface after ion sputtering

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