Position sensitive TCT evaluation of irradiated 3D-stc detectors

Position sensitive transient current technique (TCT) evaluation of irradiated 3D single column type detectors is presented. The detectors produced by ITC-irst were irradiated with neutrons to 1times10¹⁴ , 5times10¹⁴ and 5times10¹⁵ ncm^-2 . A pulsed IR laser light focused to a spot of 6 mum and scanned over the entire detector with 0.5 mum resolution is used to create electron hole pairs throughout the detector simulating m.i.p. For each laser beam position the induced current shape is measured for three neighboring channels. Charge collection and sharing, current pulse shape and timing properties are studied as a function of position, voltage and fluence.