1. Ion Beam Analysis Dolly Langa Physics Department, University of Pretoria, South Africa Blane Lomberg Physics Department, University of the Western Cape, South Africa Project Supervisor: Prof Project Supervisor: Prof A.P. Kobzev Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia

2. AIM OF PROJECT Analysis of contents and depth distribution of different elements in the near surface layers of solids using Rutherford Backscattering Spectrometry (RBS) Elastic Recoil Detection (ERD) Particle Induced X-ray Emission (PIXE)

3. OUTLINE 1.AIM OF PROJECT 2.VAN DER GRAAFF ACCELERATOR 3.PRINCIPLE OF ION BEAM ANALYSIS USED 4.RESULTS AND DISCUSSION 5.CONCLUSION

4. VAN DE GRAAFF ACCELERATOR

5. Van de Graaff Accelerator Parameters at JINR Produces the beams of helium ions and protons with energy in regions 0.9-3.5 MeV Helium intensity less than 10  A and proton intensity up to 30  A. Energy spread less than 500 eV The accelerator belt moves at 20 m/s The accelerator is placed in a tank under pressure of 10 atmospheres of dry nitrogen. The accelerator EG-5 has six beam lines.

6. Rutherford Backscattering Spectrometry (RBS) PRINCIPLE OF ION BEAM ANALYSIS USED Conti..

7. RESULTS AND DISCUSSION RBS spectrum for the sample with the Fe and Ti layers on Si substrate, with Ti layer containing Oxygen. E He = 2.035 MeV  = 10 0  = 170 0 Si Substrate Oxygen Fe Ti Calibration: Calibration offset = 35.72 keV Energy per channel = 1.8782 keV/ch Thickness: Fe = 76 nm Ti = 62 nm Concentrations in Ti layer: Ti = 30 at % O = 70 at %

8. RBS spectrum for the sample with the Ge and Si multi-layers on Si substrate Si Ge Si substrate E He = 1 MeV  = 30 0  = 20 0  = 170 0

9. PRINCIPLE OF ION BEAM ANALYSIS USED Rutherford Backscattering Spectrometry (RBS) and Elastic Recoil Detection (ERD) setup

10. C O Si RBS and ERD spectra E He = 2.297 MeV  = 75 0  = 30 0  = 135 0 E He = 2.297 MeV  = 75 0  = 75 0  = 30 0 Thickness: (C) = 170 nmThickness (O) = 20 nm Si = 26 at %Si = 70 at % H = 40 at %H = 20 at % C = 34 at %O = 10 at % Thickness (H) = 190 nm

11. PRINCIPLE OF ION BEAM ANALYSIS USED Conti.. Particle Induce X-ray Emission (PIXE)

12. PIXE RBS

13. ElementConcen. At. % Method ElementConcen. At. % Method C 41 RBS K 0.1 PIXE N 20.5 RBS Ca 0.53 RBS O 28 RBS Mn 0.007 PIXE F 2.6 RBS Fe 0.14 RBS Na 2.5 RBS Cu 0.002 PIXE Mg 1.3 RBS Zn 0.01 PIXE Al 1.3 RBS As 0.001 PIXE Si 1.8 PIXE Sr 0.0006 PIXE S 0.2 RBS Zr 0.005 PIXE Cl 0.01 PIXE Ba 0.01 PIXE Aerosol analysis by PIXE & RBS

14. CONCLUSION These methods are non-destructive techniques to study materials The used methods allow the determination of depth distribution and concentration from hydrogen to heavy elements. The spectra calculations and model comparisons was executed in SIMNRA software tool, in which good agreement was achieved for RBS and ERD experiments. Furthermore, the depth resolution is done near to few nm range for these methods. The sensitivity for heavy elements is of the order 10 14 atoms/cm 2

15. THANK YOU