Structural imaging in applied materials

In the last few years the research activities at the Id01 beamline have focused on the exploitation of both coherent and incoherent sub-micron X-ray beams for the investigation of local properties of materials (interfaces, compositional gradients, etc...) and of single nanostructures.

In addition the development of full field diffraction microscopy has established a new technique for operando experiments available for users.

For these applications, nano-micro beams are obtained with Fresnel Zone Plates, KB mirrors or Be Compound Refractive Lenses in a X-ray energy range [7-15]keV, with spot sizes from 56 x 64nm - 300 x 300nm, 150nm x 200nm  and a few microns x a few microns respectively.

The sample goniometer is made up of a Symmetrie hexapod for course movements (10mm stroke in 3 axes) and piezo translation stages from PI with capacitive encoders, allowing a precision of 2 nm (100/200 micron stroke in 3 axes).

Preserving the coherence of the X-ray beam after sub-micron focalisation allows the exploitation of the coherent diffraction imaging (CDI) technique for the model-free investigation of the 3D morphology and strain state of single nano-structures through the retrieval of the "lost" phase of the measured X-ray diffraction distribution in reciprocal space. CDI, Holography and Ptychography in Bragg geometry have been successfully carried out on isolated and epitaxial semiconductors nanostructures within collaborations with the J.-Kepler University of Linz - AU and Fresnel Institute in Marseille - FR. This research aims to create a 3D X-ray strain microscope for nanostructures.

Continuous development of samples environment aim to exploit  submicron beam diffraction in diverse environments. The equipment available today at ID01 includes:

  • a light weight cryostat, cooled under liquid He flow, capable of reaching a base temperature of 2K, and compatible with the use of Scanning X-ray Diffraction Microscopy
  • a light weight furnace capable of obtaining 950oC, vacuum/ air/ gas compatibility.
  • several small volume vacuum chambers for measurement in primary vacuum