A novel high energy X-ray detector concept using CCDs

The X-ray detection efficiency of charge coupled devices (CCDs) is dependent on the thickness of the active depletion layer in the silicon, typically less than 40 μm and limited by the purity of available epitaxial substrates. For X-ray imaging, therefore, the CCD detection efficiency drops sharply above 8 keV. In this Letter, we show that, using a novel illumination geometry, CCDs can detect high energy (up to 100 keV) X-rays with reasonable efficiency and good energy resolution. A novel 2-D imaging hard X-ray detector based on this geometry is discussed.