Performance Of Thin Edgeless N-on

Performance Of Thin Edgeless N-on-p Planar Pixel Sensors For ATLAS Upgrades
Marco Bomben*,1, Alvise Bagolini2, Maurizio Boscardin2, Luciano Bosisio3, Giovanni Calderini1,4,,
Jacques Chauveau1, Gabriele Giacomini2, Alessandro La Rosa5, Giovanni Marchiori1, Nicola Zorzi2
1-Laboratoire de Physique Nucleaire et de Hautes Énergies (LPNHE) Paris, France
2-Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM) Povo di Trento (TN), Italy
3-Università di Trieste, Dipartimento di Fisica and INFN, Trieste, Italy
4-Dipartimento di Fisica E. Fermi, Università di Pisa, and INFN Sez. di Pisa, Pisa, Italy
5-Section de Physique (DPNC), Universitè de Genève, Genève, Switzerland
ABSTRACT
In view of the LHC upgrade phases towards the High Luminosity LHC (HL-LHC), the ATLAS experiment plans to upgrade
the Inner Detector with an all-silicon system. Because of its radiation hardness and cost effectiveness, the n-on-p silicon
technology is a promising candidate for a large area pixel detector.
The paper reports on the joint development, by LPNHE and FBK of novel n-on-p edgeless planar pixel sensors, making
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use of the active trench concept for the reduction of the dead area at the periphery of the device . After discussing the
sensor technology, a complete overview of the electrical characterization of the produced devices will be given (an
example is reported in Figure 1, on the left).
Measurements on irradiated devices will be presented too, together with first results on the charge collection efficiency in
the edge region, performed with special microstrips test structures ("stripixels"; see also Figure 1, on the right).
The results will be compared to device simulations we run and to other current edgeless planar productions aimed at the
ATLAS tracker upgrade for the HL-LHC.
The next step, planned for next year, is a beam test of the edgeless sensors, to measure their hit-efficiency, space-point
resolution and charge collection efficiency - in particular at the sensor periphery - with minimum ionizing particles.
Figure 1: IV curves for several pixel-like test structures with a pixel to trench distance of 200µm, differing by
the number of Guard Rings (GRs). (right) Stripixels sensor wirebonded to the Beetle Chip2
REFERENCES
1. M. Bomben et al., Development of edgeless n-on-p planar pixel sensors for future ATLAS upgrades, Nucl. Instr. and Meth. A 712 (2013) 41 -47
2. www.alibava.com