The charge collection performance of a three-dimensional diamond-graphite detector is reported. Buried graphite pillars with high aspect ratio were formed inside a single crystal synthetic diamond slab by using a femtosecond IR laser with 200 kHz of repetition rate. Grouped in two series and connected by graphite strips on the surface, eight independent 3D electrodes were used to collect the charge carriers generated by energy deposited in the detector by 90 Sr,Y β-particles. Different impinging conﬁgurations were used to test charge collection and signal dependence on voltage. Reversing the bias polarity the pulse height distribution does not changes and the charge collection saturation of any group of connected pillars was observed around 780 V (0.53 V/μm). The average charge collected by one pillars row is Q av ¼1.6070.02 fC, with electrons impinging orthogonally the rows, in such a way demonstrating full charge collection.
Conte, G., Allegrini, P., Pacilli, M., Salvatori, S., T., K., Ralchenko, V., et al. (2015). Three-dimensional Graphite electrodes in CVD Diamond: charge collection dependence on impinging b-particles geometry. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT, 799, 10-16 [10.1016/j.nima.2015.07.024].