39 research outputs found
Planar Pixel Sensors for the ATLAS tracker upgrade at HL-LHC
The ATLAS Planar Pixel Sensor R&D Project is a collaboration of 17 institutes
and more than 80 scientists. Their goal is to explore the operation of planar
pixel sensors for the tracker upgrade at the High Luminosity-Large Hadron
Collider (HL-LHC). This work will give a summary of the achievements on
radiation studies with n-in-n and n-in-p pixel sensors, bump-bonded to ATLAS
FE-I3 and FE-I4 readout chips. The summary includes results from tests with
radioactive sources and tracking efficiencies extracted from test beam
measurements. Analysis results of and ( neutron equivalent)
irradiated n-in-n and n-in-p modules confirm the operation of planar pixel
sensors for future applications
Novel Silicon n-in-p Pixel Sensors for the future ATLAS Upgrades
In view of the LHC upgrade phases towards HL-LHC the ATLAS experiment plans
to upgrade the Inner Detector with an all silicon system. The n-in-p silicon
technology is a promising candidate for the pixel upgrade thanks to its
radiation hardness and cost effectiveness, that allow for enlarging the area
instrumented with pixel detectors. We present the characterization and
performance of novel n-in-p planar pixel sensors produced by CiS (Germany)
connected by bump bonding to the ATLAS readout chip FE-I3. These results are
obtained before and after irradiation up to a fluence of 10^16 1-MeV n_eq/cm^2,
and prove the operability of this kind of sensors in the harsh radiation
environment foreseen for the pixel system at HL-LHC. We also present an
overview of the new pixel production, which is on-going at CiS for sensors
compatible with the new ATLAS readout chip FE-I4.Comment: Preprint submitted to NIM-A Proceedings (Elba 2012
Performance of novel silicon n-in-p planar Pixel Sensors
The performance of novel n-in-p planar pixel detectors, designed for future
upgrades of the ATLAS Pixel system is presented. The n-in-p silicon sensors
technology is a promising candidate for the pixel upgrade thanks to its
radiation hardness and cost effectiveness, that allow for enlarging the area
instrumented with pixel detectors. The n-in-p modules presented here are
composed of pixel sensors produced by CiS connected by bump-bonding to the
ATLAS readout chip FE-I3. The characterization of these devices has been
performed before and after irradiation up to a fluence of 5 x 10**15 1 MeV neq
cm-2 . Charge collection measurements carried out with radioactive sources have
proven the functioning of this technology up to these particle fluences. First
results from beam test data with a 120 GeV/c pion beam at the CERN-SPS are also
discussed, demonstrating a high tracking efficiency of (98.6 \pm 0.3)% and a
high collected charge of about 10 ke for a device irradiated at the maximum
fluence and biased at 1 kV.Comment: Preprint submitted to Nuclear Instruments and Methods A. 7 pages, 13
figure
Radiation hardness studies of neutron irradiated CMOS sensors fabricated in the ams H18 high voltage process
High voltage CMOS detectors (HVCMOSv3), fabricated in the ams H18 high voltage process, with a substrate resistivity of 10 âŠÂ·cm were irradiated with neutrons up to a fluence of 2Ă1016 neq/cm2 and characterized using edge-TCT. It was found that, within the measured fluence range, the active region and the collected charge reach a maximum at about 7Ă1015 neq/cm2 to decrease to the level of the unirradiated detector after 2Ă1016 neq/cm2
Performance of n-in-p pixel detectors irradiated at fluences up to 5x10**15 neq/cm**2 for the future ATLAS upgrades
We present the results of the characterization of novel n-in-p planar pixel
detectors, designed for the future upgrades of the ATLAS pixel system. N-in-p
silicon devices are a promising candidate to replace the n-in-n sensors thanks
to their radiation hardness and cost effectiveness, that allow for enlarging
the area instrumented with pixel detectors. The n-in-p modules presented here
are composed of pixel sensors produced by CiS connected by bump-bonding to the
ATLAS readout chip FE-I3. The characterization of these devices has been
performed with the ATLAS pixel read-out systems, TurboDAQ and USBPIX, before
and after irradiation with 25 MeV protons and neutrons up to a fluence of
5x10**15 neq /cm2. The charge collection measurements carried out with
radioactive sources have proven the feasibility of employing this kind of
detectors up to these particle fluences. The collected charge has been measured
to be for any fluence in excess of twice the value of the FE-I3 threshold,
tuned to 3200 e. The first results from beam test data with 120 GeV pions at
the CERN-SPS are also presented, demonstrating a high tracking efficiency
before irradiation and a high collected charge for a device irradiated at
10**15 neq /cm2. This work has been performed within the framework of the RD50
Collaboration.Comment: Proceedings of the Conference "Technology and Instrumentation in
Particle Physics 2011
Recent Technological Developments on LGAD and iLGAD Detectors for Tracking and Timing Applications
This paper reports the last technological development on the Low Gain
Avalanche Detector (LGAD) and introduces a new architecture of these detectors
called inverse-LGAD (iLGAD). Both approaches are based on the standard
Avalanche Photo Diodes (APD) concept, commonly used in optical and X-ray
detection applications, including an internal multiplication of the charge
generated by radiation. The multiplication is inherent to the basic n++-p+-p
structure, where the doping profile of the p+ layer is optimized to achieve
high field and high impact ionization at the junction. The LGAD structures are
optimized for applications such as tracking or timing detectors for high energy
physics experiments or medical applications where time resolution lower than 30
ps is required. Detailed TCAD device simulations together with the electrical
and charge collection measurements are presented through this work.Comment: Keywords: silicon detectors, avalanche multiplication, timing
detectors, tracking detectors. 8 pages. 8 Figure
Characterization of proton irradiated 3D-DDTC pixel sensor prototypes fabricated at FBK
In this paper we discuss results relevant to 3D Double-Side Double Type
Column (3D-DDTC) pixel sensors fabricated at FBK (Trento, Italy) and oriented
to the ATLAS upgrade. Some assemblies of these sensors featuring different
columnar electrode configurations (2, 3, or 4 columns per pixel) and coupled to
the ATLAS FEI3 read-out chip were irradiated up to large proton fluences and
tested in laboratory with radioactive sources. In spite of the non optimized
columnar electrode overlap, sensors exhibit reasonably good charge collection
properties up to an irradiation fluence of 2 x 10**15 neq/cm2, while requiring
bias voltages in the order of 100 V. Sensor operation is further investigated
by means of TCAD simulations which can effectively explain the basic mechanisms
responsible for charge loss after irradiation.Comment: Preprint submitted to Nuclear Instruments and Methods A, 11 pages, 13
fig
Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip
The ATLAS Collaboration will upgrade its semiconductor pixel tracking
detector with a new Insertable B-layer (IBL) between the existing pixel
detector and the vacuum pipe of the Large Hadron Collider. The extreme
operating conditions at this location have necessitated the development of new
radiation hard pixel sensor technologies and a new front-end readout chip,
called the FE-I4. Planar pixel sensors and 3D pixel sensors have been
investigated to equip this new pixel layer, and prototype modules using the
FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN
SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test
results are presented, including charge collection efficiency, tracking
efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS