Leader: Kruglyak Anastasia Igorevna

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

Scientific problem:

Determining the elemental composition of samples poses a significant challenge in materials science. These materials frequently contain a dense matrix of heavy elements coexisting with light elements (e.g., hydrogen, oxygen) and trace impurities. Conventional single-technique analyses fail to provide a complete and accurate compositional profile:
• RBS: Excellent for depth profiling of heavy elements, but suffers from low sensitivity and overlapping signals when detecting light elements or low-concentration impurities on a heavy substrate.
• ERD: Highly sensitive to light elements (especially for Hydrogen depth profiling), but cannot analyze heavy matrix elements.
• PIXE: An excellent solution for trace element sensitivity (ppm level) for medium and heavy elements, but it completely lacks depth resolution and cannot detect ultra-light elements.
To avoid destructive sputtering and obtain absolute quantitative results, a synergistic Ion Beam Analysis (IBA) approach combining RBS, ERD, and PIXE is required.

Objective: 

1. Technical: Understand the operational principles of RBS, ERD, and PIXE.
2. Application: Apply the triple-technique approach to conduct an experiment on user-provided material samples. This includes determining the elemental composition and finding the depth profile of elements within the samples.
3. Data Analysis: Calibrate the collected spectra to produce a single, unified compositional profile of the material without conflicting element percentages.

Tasks:

1. Study the physics of each technique: RBS, ERD, and PIXE.

2. The experimental setup: beam energy requirements (e.g., 2-3 MeV protons/alpha-particles), detector positioning (backscattering detector for RBS, forward recoil detector with an absorber foil for ERD, and Si(Li)/SDD X-ray detector for PIXE).

3. Software setup: SIMNRA for RBS/ERD analysis and standard PIXE analysis software.

4. Optimize the geometry for ERD (typically 15° - 30° for incident and exit angles), while the RBS and PIXE detectors maintain an optimal line-of-sight to the beam. Samples: thickness, elemental depth profiles, depth-dependent hydration/hydrogenation layers, and trace impurity concentrations in parts-per-million (ppm).

Research facilities: 

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

Minimum requirements for applicants

Solid educational background (physics, chemistry, mathematics, nanotechnology, electronics); problem-solving and practical hands-on skills; creativity; ability to work both independently and collaboratively in a multidisciplinary team; diligence and a high degree of responsibility.