Leader: Aradeib Ayman

Work E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. 

Scientific problem:

In materials science, particularly in thin-film and semiconductor technologies, precise determination of stoichiometry and elemental depth profiles is critical for understanding the physicochemical properties of materials. Rutherford Backscattering Spectroscopy (RBS) stands out as a standard technique due to its ability to perform quantitative, non-destructive analysis with nanometer-scale depth resolution. Configuring experimental geometries and optimizing beam energies to mitigate artifact signals (e.g., multiple scattering, surface roughness, and channeling effects) during spectrum fitting remain a challenging task for young researchers. Therefore, it is important to understand how to work with the RBS spectrometry system and apply it to analyze a specific material system. 

Objective: 

• Technical: To study the physical principles of ion-matter interactions and the hardware architecture of an RBS system, as well as to gain proficiency in simulation/analysis software (SIMNRA).
• Application: To use the RBS technique to determine the thickness (in atoms/cm² or nm) and stoichiometry of a specific thin-film sample system (e.g., semiconductor oxides).
• Optimization: To determine the setup parameters (incident ion beam energy, tilt angle, and detector angle) and the calibration procedure for RBS.

Tasks:

1. Study the principles of RBS: kinematic factor (K), differential scattering cross-section (dσ/dΩ), and electronic/nuclear stopping power (dE/dx).
2. Review the block diagram of the RBS system (ion source, particle accelerator, scattering chamber, surface barrier detector, and Multi-Channel Analyzer (MCA)).
3. Install and use the SIMNRA and SRIM/TRIM software (to determine ion concentration and ion range in matter).
4. Create a virtual target sample structure and define the experimental geometry configuration in SIMNRA.
5. Run simulations by varying the incident ion beam energy (e.g., from 1.0 MeV to 2.5 MeV) to optimize experimental conditions.
6. Conduct RBS experiments using the accelerator.
7. Perform energy calibration for the experimental system.

Research facilities: 

EG-5 accelerator,  ion beam analysis (IBA) module, multichannel ADC

Minimum requirements for applicants

Solid educational background (physics, chemistry, mathematics, nanotechnology, electronics); hands-on skills; diligence and a high degree of responsibility.

Application of Rutherford Backscattering Spectroscopy (RBS) in materials science