Charge collection measurements in single-type column 3D sensors

Development of 3D Detectors at FBK-irst

“…CCE tests with Sr 90 β sources were performed on pad detectors at INFN Florence and on strip detectors at SCIPP and Freiburg. A comparison between the results achieved in pad detectors with analog DAQ and strip detectors with binary DAQ is reported in [16], showing the same dependence of the collected charge with the bias voltage, in agreement with the simple picture of the depletion, i.e., with a rapid depletion between columns and a slow, planar-diode like depletion beyond that. The importance of the ballistic deficit is highlighted in Fig.…”

“…As an example, Fig. 11 shows the simulated signals induced by a minimum ionizing particle hitting close to the ohmic column (i.e., in the worst-case situation) in a n-on-p detector with d = 25 µm and t = 250 µm, irradiated at 1 × 10 16 1 MeV eq. n/cm 2 for different bias voltages (note that the lateral depletion voltage is 400 V).…”

“…Simulated transient signals in response to a mip hitting close to the ohmic column in a 3D-DDTC detector irradiated at 1 × 1016 1 MeV eq. n/cm 2 for different bias voltages: a) current signals; b) equivalent charge signals at the output of a semigaussian CR-(RC)3 shaper with 20 ns peaking time.…”

Overview of the recent activities of the RD50 collaboration on radiation hardening of semiconductor detectors for the sLHC

“…The main advantage of these detectors is the simplified production method obtained by the single type of column doping, requiring only one doping step after column etching. These devices have been successfully tested with C-V and I-V measurements, laser pulses and test-beam [51][52][53][54]. A good agreement has been found between measurements and simulations, showing that the 3d processing is well controlled.…”

Comparing radiation tolerant materials and devices for ultra rad-hard tracking detectors

“…4, it is evident that for fluences below 2-4 Â 10 15 cm À2 , thick, planar, p-type MCz and FZ detectors exhibit superior performance in terms of radiation hardness. Beyond this fluence threshold, the highest charge collection values are measured for 3D devices [21], characterised by columnar pn junctions inside the silicon bulk [22]. Up to now only 3D detectors on standard n-type FZ Si with a thickness of 235 mm have been tested with high radiation (although only with a laser source, which introduces a uncertainty about the absolute normalisation) [20].…”