P. Breugnon

A measurement of Lorentz angle and spatial resolution of radiation hard silicon pixel sensors

Silicon pixel sensors developed by the ATLAS collaboration to meet LHC requirements and to withstand hadronic irradiation to fluences of up to

Application of a hybrid pixel detector to powder diffraction

10^{15} n_eq/cm^{2}

XPAD: pixel detector for material sciences

have been evaluated using a test beam facility at CERN providing a magnetic field. The Lorentz angle was measured and found to alter from 9.0 deg. before irradiation, when the detectors operated at 150 V bias at B=1.48 T, to 3.1 deg after irradiation and operating at 600 V bias at 1.01 T. In addition to the effect due to magnetic field variation, this change is explained by the variation of the electric field inside the detectors arising from the different bias conditions. The depletion depths of irradiated sensors at various bias voltages were also measured. At 600 V bias 280 micron thick sensors depleted to ~200 micron after irradiation at the design fluence of 1 10^{15} 1 MeV n_eq/cm2 and were almost fully depleted at a fluence of 0.5 * 10^{15} 1 MeV n_eq/cm2. The spatial resolution was measured for angles of incidence between 0 deg and 30 deg. The optimal value was found to be better than 5.3 micron before irradiation and 7.4 micron after irradiation.

XPAD : pixel detector for material sciences

Results obtained using a hybrid pixel photon-counting detector in powder diffraction experiments are presented. The detector works at room temperature and its dynamic response ranges from 0.01 photons pixel(-1) s(-1) up to 10(6) photons pixel(-1) s(-1). The pixel sizes are 0.33 mm x 0.33 mm for a total area of 68 mm x 68 mm. On recording high-resolution diffraction patterns of powders, a reduction of the experimental time by more than a factor of 20 is obtained without loss of data quality. The example of an X-zeolite shows that such detectors can be used for very demanding anomalous experiments. In situ experiments of quenching liquid oxides show that frames of 0.01 s can be achieved for studying such processes.

Performance and Applications of the CdTe- and Si-XPAD3 photon counting 2D detector

Currently available 2D detectors do not make full use of the high flux and high brilliance of third generation synchrotron sources. The XPAD prototype, using active pixels, has been developed to fulfil the needs of materials science scattering experiments. At the time, its prototype is build of eight modules of eight chips. The threshold calibration of /spl ap/4 10/sup 4/ pixels is discussed. Applications to powder diffraction or SAXS experiments prove that it allows to record high quality data.

Design and construction of the ClearPET/XPAD small animal PET/CT scanner

Currently available 2D detectors do not make full use of the high flux and high brilliance of third generation synchrotron sources. The XPAD prototype, using active pixels, has been developed to fulfil the needs of materials science scattering experiments. At the time, its prototype is build of eight modules of eight chips. The threshold calibration of /spl ap/4 10/sup 4/ pixels is discussed. Applications to powder diffraction or SAXS experiments prove that it allows to record high quality data.

The Hybrid Pixel Single Photon Counting Detector XPAD

The XPAD3 is the third generation of a single photon counting chip developed in collaboration by SOLEIL Synchrotron, the Institut Neel and the Centre de Physique de Particules de Marseille (CPPM). The chip contains 9600 pixels of 130 μm side and a counting electronic chain with an adjustable low level threshold in each pixel. Imaging and detection performance (detective quantum efficiency, modulation transfer function and energy resolution) of the XPAD3 detectors hybridized with Si and CdTe sensors have been evaluated and compared using monochromatic synchrotron X-rays beam. A second version of the chip, optimized for pump-probe experiments, has been realized and successfully tested. Three 7.3 cm x 12.5 cm Si-XPAD3 imagers, composed of 8 silicon modules (7 chips per module) and one 2.1 cm x 3.1 cm CdTe-XPAD3 imager (4 chips) have been constructed and successfully used for synchrotron diffraction experiments and biomedical imaging.

A Tezzaron-Chartered 3D-IC electronic for SLHC/ATLAS hybrid pixels detectors test results and irradiations performance

In this study, we present a small animal hybrid PET/CT scanner for simultaneous X and gamma ray scans of the same field of view. It is based on the high resolution PET scanner demonstrator ClearPET developed within the Crystal Clear Collaboration and on the prototype X-ray hybrid pixel detector XPAD3 developed at CPPM. The complete hybrid system has been studied using the GATE Monte Carlo simulation platform. The final design includes the PET detectors appropriately shielded, the XPAD3 detector and a collimated RTW X-ray tube. First, we present experimental measurements that demonstrate the feasibility of acquiring PET data in presence of an X-ray beam scattered by a water phantom hosting a positron emitter point source. Then, we present first images of simultaneous PET and CT acquisitions of several phantoms and a mouse.

XPAD: A photons counting pixel detector for material sciences and small-animal imaging

The XPAD detector is a 2D X‐ray imager based on hybrid pixel technology, gathering 38400 pixels on a surface of 68*68 mm2. It is a photon counting detector, with low noise, wide dynamic range and high speed read out, which make it particularly suitable for third generation synchrotron applications, such as diffraction, small angle X‐ray scattering or macro‐molecular crystallography, but also for small animal imaging. High resolution powder diffraction data and in situ scattering data of crystallization of liquid oxides are presented to illustrate the properties of this detector, resulting in a significant gain in data acquisition time and a capability to follow fast kinetics in real time experiments. The characteristics of the future generation of XPAD detector, which will be available in 2007, are also presented.

A 20 kpixels CdTe photon-counting imager using XPAD chip

The ATLAS pixel collaboration has started in 2008 a R&D program to use the latest advances in 3-D electronics technology in order to develop a new Front-End (FE) chip for a vertex detector for High Energy Physics (HEP). This program using the commercial Tezzaron-Chartered 0.13µm LP technology should be able to fulfill the requirements imposed by the ten times higher luminosity given by the High Luminosity LHC accelerator. The FE-TC4-P1 is a hybrid pixel read-out chip realized by the first MPW for HEP. This three dimensional chip includes an analog part called FE-TC4-AE and two digital parts called FE-TC4-DS and FE-TC4-DC. At the same time, several prototypes were realized in Chartered 0.13µm LP technology, in order to disentangle from effects induced by 3D architecture. These FE-C4-P1,2,3 prototypes have proved a good radiation hardness up to 400Mrads as well as good performances. This paper presents results from the FE-TC4-P1 chip which has been recently tested and irradiated.