Bruker D8 General Area Detector Diffraction System (GADDS)
Bruker D8 General Area Detector Diffraction System (GADDS)
Bard SB56 (Mark Pfeifer; Secondary Staff: Kevin Silverstein)
The Bruker D8 Advance General Area Detector Diffraction System (GADDS) is a versatile X-ray diffractometer that can be used to readily survey diffraction patterns from polycrystalline samples with unknown partial orientation (texture) and spatial variation. Quickly interchangeable apertures are used to define the size of the X-ray beam, while an off-axis laser and microscope enable quick alignment of the sample’s region of interest in the beam and on multiple rotation axes. An area detector images diffraction over a large solid angle, and its position can be scanned simultaneously with the source angle.
The GADDS includes large sample translations along 3 axes as well as rotation about the vertical axis. This permits the study of large samples such as machined parts or wafers with combinatorial variation of deposited materials, although signal to noise limits the effectiveness of studying films thinner than 1 micron.
Standard operation of the GADDS uses Cu K-α radiation which leads to a large fluorescent background when studying Fe-bearing samples. The source can be occasionally switched to operation with Co to eliminate this noise source. Small-angle X-ray diffraction (>1.5°) measurements are challenging but possible.
Specifications
- Phase identification of polycrystalline materials with spatial resolution down to 0.3 mm
- Observation of 2D diffraction pattern to characterize systems with partial orientational ordering
- Sample translation: 40 mm in X, Y, Z
- Continuous sample rotation while X-ray spot stays fixed on sample
- Small angle scattering (> 2°) possible with additional configuration
- Jade analysis software and ICCD database license
- 1.6 kW Cu-Kα source, can be changed to Co source to avoid Fe fluorescence
- Easily changeable beam size of 0.3, 0.5, 1.0, 2.0 mm
- Overhead camera and off-axis laser for alignment
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