Charge-collection efficiency and long-term stability of single-crystal CVD diamond detector under different carrier-drift conditions

Sato, Yuki  ; Murakami, Hiroyuki*; Shimaoka, Takehiro*; Tsubota, Masakatsu*; Kaneko, Junichi* 

We investigated the performance of a charged particle detector fabricated using single-crystal diamond grown by chemical vapor deposition. The detector was able to identify four different Am -particle energies (5.389, 5.443, 5.486, and 5.545 MeV) because of its superior intrinsic energy resolution of 0.4% (full width at half maximum). The charge collection efficiency inside the diamond crystal was 98% for both electrons and holes. The diamond detector also exhibited no significant degradation in terms of pulse height spectra and energy resolution during operation for more than 100 h in the case of mainly electron drift inside the diamond crystal. In contrast, the shapes of the pulse height spectra measured under hole drift condition deteriorated due to the polarization phenomenon.