High-resolution X-ray diffractometers

What it does

X-rays reflect from a crystal only at the Bragg angle, set by the spacing of its lattice planes. A high-resolution diffractometer measures that angle very precisely: a copper tube, an X-ray mirror and a Bartels monochromator make a beam that is nearly parallel and of a single wavelength, and a goniometer turns the sample in small, precise steps.

From the diffraction peaks we get the orientation of the lattice planes relative to the surface (the miscut), the curvature of the lattice in bent crystals, strain and defects. With the triple-axis analyser we record reciprocal space maps, which tell a change in lattice spacing apart from a tilt of the planes.

We have two high-resolution systems. The X'Pert³ MRD XL has a large cradle that carries whole wafers and maps them point by point.

What we use it for

• Miscut of wafers and coupons

  Silicon wafers and coupons for cosine and for the ESA project ASTROLAUE2.

• Laue lens crystals

  The orientation of every crystal in the OTELLO Laue lens, aligned to 30 µrad.

• Bent crystals

  Curvature and lattice quality of bent crystals for beam steering and X-ray optics.

• Oriented calorimeters

  Co-alignment of PbWO₄ crystals, so that their axes point the same way in the calorimeter.

Working with us

We can measure the orientation, miscut, curvature and lattice quality of your crystals and wafers in joint projects.