2009

A portable readout system for microstrip silicon sensors
R. Marco-Hernandez (on behalf of the ALIBAVA Collaboration)
IEEE Trans.Nucl.Sci. Vol. 56, pp.1642-1649, 2009
doi:10.1109/TNS.2009.2017261

Abstract: A readout system for microstrip silicon sensors has been developed. This system is able to measure the collected charge in one or two microstrip silicon sensors by reading out all the channels of the sensor(s), up to 256. The system can operate either with non-irradiated and irradiated sensors as well as with n-type and p-type microstrip silicon sensors. Heavily irradiated sensors will be used at the Super Large Hadron Collider, so this system can be used to research the performance of microstrip silicon sensors in conditions as similar as possible to the Super Large Hadron Collider operating conditions. The system has two main parts: a hardware part and a software part. The hardware part acquires the sensor signals either from external trigger inputs, in case of a radioactive source setup is used, or from a synchronised trigger output generated by the system, if a laser setup is used. The software controls the system and processes the data acquired from the sensors in order to store it in an adequate format. The main characteristics of the system will be described. Results of measurements acquired with n-type and p-type non-irradiated detectors using both the laser and the radioactive source setup will be also presented and discussed. © 2006 IEEE.

Characterization of irradiated P-type silicon detectors by the ALIBAVA system
M. Minano, C. Garcia, C. Lacasta, R. Marco-Hernandez, S. Marti-Garcia, U. Soldevila
11th Pisa Meeting on Advanced Detectors, May 2009, Isola Elba, Italy
Nuclear Inst. & Meth. A, Vol. 617, Issue 1-3, Pages 565-567
doi:10.1016/j.nima.2009.09.040

Abstract: The ATLAS Tracker System has been designed to withstand the radiation doses accumulated with 10 years of running at a LHC luminosity of 1034cm-2s-1. The operation under an upgraded luminosity of 1035cm-2s-1 (superluminous LHC) implies to upgrade the semiconductor tracking systems of the LHC experiments. The expected dose for the inner detector trackers at the superluminous LHC experiments is up to 1016 1 MeV equivalent neutron cm-2 after the envisaged five years of operation. Investigations have showed arguments in favour of implementing the n-type strip readout on a p-type substrate (currently the Semiconductor Tracker, SCT, uses p-type strip readout on a n-type substrate). In order to evaluate the radiation damage p-type microstrip sensors have been irradiated with neutrons and protons at several fluxes up to 1016cm-2. Electrical and charge collection efficiency measurements have been carried out by means of a radioactive source setup as well as by an infrared laser illumination and the measurements compared with a non-irradiated sensor as a reference. The ALIBAVA acquisition system has been used. It is a compact and portable system which contains two front-end readout ASIC chips to acquire the detector signals. One of the advantages of the ALIBAVA system is that it uses LHC speed electronics. Another one is that it performs a pulse by pulse and strip by strip analysis.

Studies on charge collection of p-type silicon detectors under neutron irradiation expected for Super-LHC
M. Minano, C. Garcia, C. Lacasta, S. Marti i Garcia, R. Marco-Hernandez, U. Soldevila
IEEE Nuclear Science Symposium and Medical Imaging Conference, IEEE NSS-MIC, Oct. 2009, Orlando FL, USA.
2009 IEEE NSS-MIC Conference Record, pp.747-750.
doi:10.1109/NSSMIC.2009.5402201

Abstract: The existing technology used in the ATLAS Tracker is at the limit for performances of 10 years of running at a LHC peak luminosity of 1034 cm-2s-1. The operation under an upgraded luminosity of 1035 cm-2s-1 (Super-LHC) will imply a corresponding increase of the radiation dose. The expected dose for the inner detector tracker at the Super-LHC is up to 1 × 1016 equivalent neutron cm-2 in comparison with a dose of 1 × 1015 equivalent neutron cm-2 at the LHC after the envisaged 10 years of operation. So, the classic concept of p-on-n silicon microstrip detector as used in the current Semiconductor Tracker (SCT) in ATLAS needs to be abandoned for the Super-LHC. Investigations with n-on-p silicon sensors are showing arguments in favor of implementing these technologies in harsh radiation environment as the Super-LHC. This paper reports about studies with p-type sensors undergoing high radiation doses of neutrons in terms of their charge collection efficiency. A significant contribution to the radiation damage to the sensors in the tracker volume is due to backscattered neutrons so it is important to know the sensor performance under this kind of irradiation. Microstrip sensors from two different suppliers have been tested and a new analogue acquisition system called ALIBAVA system has been used to carry out the measurements.

Performance of the ALIBAVA portable readout system with irradiated and non-irradiated microstrip silicon sensors
R. Marco-Hernandez (on behalf of the ALIBAVA collaboration)
European Physical Society Europhysics Conference on High Energy Physics EPS-HEP, Krakow, Poland, July 2009
Proceedings of Science,(EPS-HEP 2009)152

Abstract: A readout system for microstrip silicon sensors has been developed as a result of collaboration among the University of Liverpool, the CNM of Barcelona and the IFIC of Valencia. The name of this collaboration is ALIBAVA and it is integrat ed in the RD50 Collaboration. This system is able to measure the collected charge in one or two microstrip silicon sensors by reading out all the channels of the sensor(s), up to 256, as an analogue measurement. The system uses two ASIC chips to read out the detector(s). The system can operate either with non-irradiated and irradiated sensors as well as with n-type and p-type microstrip silicon sensors. Heavily irradiated sensors will be used at the SLHC, so this system is being used to research the performance of microstrip silicon sensors in conditions as similar as possible to the SLHC operating conditions The system has two main parts: a hardware part and a software part. The hardware part acquires the sensor signals either from external trigger inputs, in case of a radioactive source setup is used, or from a synchronised trigger output generated by the system, if a laser setup is used. The software controls the system and processes the data acquired from the sensors in order to store it in an adequate format. The main characteristics of the system will be described. Results of measurements acquired with n-type and p-type irradiated and non-irradiated detectors using both the laser and the radioactive source setup will be also presented and discussed.