NASA NTRS1985
Interacting quantum efficiencies in excess of 50 percent have been demonstrated with CCDs throughout the spectral range 600-9,00 A, and comparable sensitivity is expected to continue to wavelengths as short as a few Angstroms. Nondispersive X-ray spectra throughout the 250-8000 V range have been obtained with an FWHM spectral resolution of 200-250 eV. At present, however, both spectral and spatial resolution is limited at some energies by the diffusion of photogenerated charge into more than one picture element. Progress in reducing charge diffusion is reported, with particular attention given to a theoretical diffusion model and its implications for further improvement.