SCD DETECTORS

Non-imaging X-ray spectroscopy with a swept charge device. Swept Charge Devices (SCDs), such as e2v technologies CCD54 and C1XS devices with four CCD54 detectors in on one ceramic package (shown in the images below), offer a low cost, large area, fast read-out alternative to the CCD, for situations where spatial information is not required. These devices are designed to operate at temperatures that can be achieved using Peltier cooling, so that liquid nitrogen is not required, making them a good replacement for the Si(Li), PIN and SDD devices.

SCDs are:

  • Low cost
  • Efficient over the 0.5-10keV band
  • Large area, up to 400 mm2
  • Low noise; typically ~5 electrons rms, giving 80 eV FWHM at 1keV and 130eV FWHM at 6keV
  • High SNR; peak to background ratio of 4000:1 with collimation
  • A suitable replacement for Si(Li), PIN and SDD devices
  • Able to be operated warm (without LN2)
  • Fast to read-out

The figure below shows a spectrum obtained from vanadium using an SCD, showing the good peak to background of in excess of 3000:1 (without collimation).