Bard Hall SB56
The Bruker D8 Advance General Area Detector Diffraction System (GADDS) is a versatile x-ray diffractometer which can be used to readily survey diffraction 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 fertical 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 affectiveness 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.