Four-Dimensional Isotope-Sensitive Material Depth Profiling Using Cold Neutrons (N4DP)

Within this project we are extending the existing PGAA instrument at the FRM II by an option for neutron-based four-dimensional profiling (N4DP). This enables the non-destructive quantitative mapping of local distributions of light elements like 3He, 6Li, 10B or 14N with high sensitivity and resolution nearly independent of the bulk composition.

The project is conducted in close collaboration with Roman Gernhäuser (ZTL, Physik-Department), Ralph Gilles (MLZ) and Zsolt Revay (MLZ / PGAA).

Properties of the Neutron Depth Profiling technique:

  • Non-destructive quantitative analytical technique
  • Detection of specific stable isotopes: 3He, 6Li, 10B, 14N, 17O, 33S, 35Cl
  • Detection of radioactive isotopes: 7Be, 22Na, 37Ar, 40K, 59Ni, 210Po
  • Detection of concentration profiles of given isotopes in almost any material matrix
  • Accessible depth range material specific. Maximum range in solids <50µm
  • Depth resolutions material dependent. Depth resolutions down to 5nm possible

Typical applications of NDP at the PGAA beamline

Overview of typical application branches of Neutron Depth Profiling at the PGAA beamline, shown together with already performed measurements:

  • Manufacture quality control
    • Surface analysis of Boron in Borofloat glasses (Neutron-guide material)
    • Boron implantation profiling in Silicon substrates
    • 3He implantation profiling in Silicon substrates
  • Fundamental Nuclear Physics
  • Materials Science and Engineering
    • Boron profiling in CoRe-based superalloys for next-generation gas turbine heat-shieldings
    • Composition and homogeneity determination of lithium-containing single crystals
  • Energy Systems
    • Lithium immobilization profiling in electrodes for Lithium-Ion-Batteries
    • Operando tracking of Lithium reversibly incorporated in electrodes during dis-/charging
    • Lithium-/Sodium-based electrodes for future battery systems beyond Litium-Ion-Batteries
    • Lithium-based systems for Organic Light Emitting Devices (OLEDs)
  • Healthcare
    • Tracking of Lithium accumulation in the Human Brain

Hints for Users:

  • Areal sample size max. 150x150 mm, sample sizes larger than 10x10 mm favorable.
  • Reduce thickness of samples as much as possible in order to reduce background signal.
  • Measurements within the framework of Rapid-Access or Full Proposals at MLZ possible.
  • For a feasability check of the application please contact one of the following: lukas.werner@tum.de, markus.trunk@tum.de, maerkisch@ph.tum.de, roman.gernhaeuser@ph.tum.de

We are currently looking for talented and motivated students for this BMBF funded project. If you are interested, please contact Roman Gernhäuser or Bastian Märkisch.