Abstract-P-channel, backside illuminated silicon CCDs were developed and fabricated on high-resistivity n-type silicon. Devices have been exposed up to 1 × 10 11 protons/cm 2 at 12 MeV. The charge transfer efficiency and dark curent were measured as a function of radiation dose. These CCDs were found to be significantly more radiation tolerant than conventional n-channel devices. This could prove to be a major benefit for long duration space missions.

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W e present initial results of a position-sensitive photodiode/BGO detector for high resolution, multi-layer positron emission tomography (PET). Position sensitivity is achieved by dividing the 3 mm x 20 mm rectangular photosensitive area along the diagonal to form two triangular segments. Each segment was individually connected to a low-noise charge amplifier. The photodiodes and crystals were cooled to -100 "C to reduce dark current and increase the BGO signal. With an amplifier peaking time of 17 psec, the sum of the signals (5 11 keV photopeak) was 3200 electrons with a full width at half maximum (fwhm) of 750 electrons. The ratio of one signal to the sum determined the depth of interaction with a resolution of 11 mm fwhm.

A new type of p-channel CCD constructed on high-resistivity n-type silicon was exposed to 12 MeV protons at doses up to 1x10 11 protons/cm 2 . The charge transfer efficiency was measured as a function of radiation dose and temperature. We previously reported that these CCDs are significantly more tolerant to radiation damage than conventional n-channel devices. In the work reported here, we used pocket pumping techniques and charge transfer efficiency measurements to determine the identity and concentrations of radiation induced traps present in the damaged devices.