MPI Halbleiterlabor

München, Germany

MPI Halbleiterlabor

München, Germany
SEARCH FILTERS
Time filter
Source Type

Foucar L.,Max Planck Advanced Study Group | Foucar L.,Max Planck Institute For Medizinische Forschung | Barty A.,German Electron Synchrotron | Coppola N.,German Electron Synchrotron | And 20 more authors.
Computer Physics Communications | Year: 2012

The Max Planck Advanced Study Group (ASG) at the Center for Free Electron Laser Science (CFEL) has created the CFEL-ASG Software Suite CASS to view, process and analyse multi-parameter experimental data acquired at Free Electron Lasers (FELs) using the CFEL-ASG Multi Purpose (CAMP) instrument Strüder et al. (2010) [6]. The software is based on a modular design so that it can be adjusted to accommodate the needs of all the various experiments that are conducted with the CAMP instrument. In fact, this allows the use of the software in all experiments where multiple detectors are involved. One of the key aspects of CASS is that it can be used either 'on-line', using a live data stream from the free-electron laser facility's data acquisition system to guide the experiment, and 'off-line', on data acquired from a previous experiment which has been saved to file. © 2012 Elsevier B.V. All rights reserved.


Schlosser D.M.,PNSensor GmbH | Lechner P.,PNSensor GmbH | Lutz G.,PNSensor GmbH | Niculae A.,PNDetector GmbH | And 11 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

To expand the detection efficiency Silicon Drift Detectors (SDDs) with various customized radiation entrance windows, optimized detector areas and geometries have been developed. Optimum values for energy resolution, peak to background ratio (P/B) and high count rate capability support the development. Detailed results on sensors optimized for light element detection down to Boron or even lower will be reported. New developments for detecting medium and high X-ray energies by increasing the effective detector thickness will be presented. Gamma-ray detectors consisting of a SDD coupled to scintillators like CsI(Tl) and LaBr3(Ce) have been examined. Results of the energy resolution for the 137Cs 662 keV line and the light yield (LY) of such detector systems will be reported. © 2010 Elsevier B.V. All rights reserved.


Porro M.,Max Planck Institute for Extraterrestrial Physics | Andricek L.,MPI Halbleiterlabor | Andricek L.,Max Planck Institute for Physics | Bombelli L.,Polytechnic of Milan | And 10 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

The new DSSC (DEPFET sensor with signal compression) detector system is being developed in order to fulfil the requirements of the future XFEL in Hamburg. The instrument will be able to record X-ray images with a maximum frame rate of 5 MHz and to achieve a high dynamic range. The system is based on a silicon pixel sensor with a new designed non-linear-DEPFET as a central amplifier structure. The detector chip is bump-bonded to mixed signal readout ASICs that provide full parallel readout and temporary data storage. The signals coming from the detector are processed by an analog filter, immediately digitized by 8-ENOB ADCs and locally stored in a custom designed memory. The ASICs are designed in 130 nm CMOS technology. During the time gap of 99 ms of the XFEL machine, the digital data are sent off the focal plane to a DAQ electronics that acts as an interface to the back-end of the whole instrument. The pixel sensor has been designed so as to combine high energy resolution at low signal charge with high dynamic range. This has been motivated by the desire to be able to be sensitive to single low energy photons and, at the same time, to measure at other positions of the detector signals corresponding to up to 104 photons of 1 keV. In order to fit this dynamic range into a reasonable output signal swing, achieving at the same time single photon resolution, a strongly non-linear characteristic is required. The new proposed DEPFET provides the required dynamic range compression at the sensor level, considerably facilitating the task of the electronics. At the same time the DEPFET charge handling capacitance is enormously increased with respect to standard DEPFETs. The sensor matrix will comprise 1024×1024 pixels of hexagonal shape with a side-length of 136μm. The simultaneous implementation of the 5 MHz frame rate, of the single low-energy photon resolution and of the high dynamic range goes beyond all the existing instruments and requires the development of new concepts and technologies. © 2010 Elsevier B.V. All rights reserved.


Porro M.,Max Planck Institute for Extraterrestrial Physics | Bianchi D.,Polytechnic of Milan | De Vita G.,Max Planck Institute for Extraterrestrial Physics | Hartmann R.,PNSensor GmbH | And 6 more authors.
IEEE Transactions on Nuclear Science | Year: 2013

VERITAS (VErsatile Readout based on Integrated Trapezoidal Analog Shapers) is the first 128-channel ASIC developed to read out both the pnCCDs and the DEPFET arrays produced at the MPI-Halbleiterlabor in Munich. These detectors are used in a large variety of scientific applications, ranging from high-speed optical astronomy and X-ray astronomy to the new X-ray Free Electron Laser sources. The main concept of VERITAS is to provide a flexible readout chip able to cope not only with different kinds of detectors, but also with a large set of operating conditions that may require very different noise thresholds and input dynamic ranges. These can vary by more than two orders of magnitude. Every analog channel of VERITAS provides a trapezoidal weighting function. This filtering strategy had never been applied to the pnCCD before. The very first measurements obtained coupling VERITAS with a 128×,256 pnCCD are shown. With a readout time of 4 μ s/line a noise of 3.9 electrons has been measured in the highest gain mode. The resolution obtained on the Mn-Kα peak of a 55Fe source is 136 eV for single events. A noise of 30 electrons has been achieved in the lowest gain mode at a speed of 6.4 μ s/line. In this low gain setting an input charge up to 2.5× 105 electrons can be processed. These striking results fulfill the requirements of the main foreseen applications of large-size pnCCDs. In order to further improve the performance and the flexibility of the ASIC, a second version based on a fully differential architecture has been designed. The new topology allows one also to switch with the same ASIC between the source follower and drain current readout of the DEPFET sensors and to reach a processing time of about 2-3 μs/line with an electronics noise ≤10 el. For this reason the second version of VERITAS is very attractive for the proposed ESA X-ray astronomy mission ATHENA. © 1963-2012 IEEE.


Bombelli L.,Polytechnic of Milan | Bombelli L.,National Institute of Nuclear Physics, Italy | Fiorini C.,Polytechnic of Milan | Fiorini C.,National Institute of Nuclear Physics, Italy | And 4 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

The concept of active pixel sensor based on depleted P-channel FET (DEPFET) has been developed to cope with the emerging requirements of low noise and speed. The DEPFET detector/amplifier [1], thanks to an intrinsic low anode capacitance, can provide excellent energy resolution and fast readout at the same time. However, in order to fully exploit the speed capability, it is necessary to develop a new readout electronics, which is different from the ones employed up to now. For this purpose, we have developed a new front-end ASIC, named VLSI Electronic for Astronomy (VELA). The implemented circuit operates the pixels in a new current readout configuration to implement an extremely fast readout. The current version of VELA reads out 64 × 64 DEPFET matrixes with unparalleled frame rate and excellent energy resolution. The circuit architecture, the working principle, and the VELA suitability for X-ray imaging will be shown. © 2009 Elsevier B.V. All rights reserved.


Porro M.,Max Planck Institute for Extraterrestrial Physics | De Vita G.,Max Planck Institute for Extraterrestrial Physics | Herrmann S.,Max Planck Institute for Extraterrestrial Physics | Lauf T.,Max Planck Institute for Extraterrestrial Physics | And 8 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

The 64 channel ASTEROID ASIC has been developed to readout DEPFET Macro-Pixel Arrays operated in source follower mode. In particular ASTEROID will be coupled with the DEPFET Macro-Pixel sensors designed for the X-ray astronomy application BepiColombo. This is a satellite-based mission that requires a detector system with high speed readout, high energy resolution and radiation hardness properties. In the source follower operating mode of the DEPFETs, the front-end electronics is AC-coupled. This allows easy coping with non homogeneity of the pixel matrix and an easy compensation of threshold voltage shifts of the DEPFET devices due to radiation damage. In order to achieve the low noise value required at short processing time, ASTEROID implements a trapezoidal weighting function. This is the time-limited optimum filter for white series noise, which is dominant at the foreseen readout speed. The ASIC is realized in the 0.35 μm 3.3 V AMS CMOS technology. The outputs of the 64 analog channels are multiplexed to one serial output with a speed up to 20 MHz. Thanks to the new multiplexer architecture adopted, ASTEROID is the only ASIC that allows window-mode readout of the pixel matrices, i.e. that allows to address selectively arbitrary sub-areas of the pixel array or even to readout different sub-areas at different speeds. In order to fully operate the 64 channels in parallel, the ASIC contains a digital section that generates the timing signals for the analog circuits. This digital section is based on SEU-immune dual port memory cells. ASTEROID has been tested for the first time with a demonstrator 64 × 64 macro-pixel Matrix of the size of 3.2 × 3.2 cm2. The energy resolution measured on the Mn - kα peak of 55Fe is of 124eV with a pixel processing time of 4.8 μs at - 80°C. This excellent result, never achieved before with source follower DEPFET at this readout speed, perfectly matches the requirements of BepiColombo Mission. © 2009 Elsevier B.V. All rights reserved.


Busca P.,Polytechnic of Milan | Busca P.,National Institute of Nuclear Physics, Italy | Peloso R.,Polytechnic of Milan | Peloso R.,National Institute of Nuclear Physics, Italy | And 9 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

Silicon drift detectors (SDDs) have shown to be a competitive device for the readout of scintillators with respect to conventional photodetectors, thanks to their high quantum efficiency and low electronics noise. Recently, they have been successfully employed in first small prototypes of Anger cameras to achieve sub-millimeter spatial resolution in gamma-ray imaging. To cover larger formats of Anger cameras, in particular in the framework of the HICAM project, specially focused on human imaging, we have developed new SDD arrays of larger active areas. To assemble photodetector planes of several cm2, we have designed a basic unit composed by a linear array of 5 SDDs of 1 cm 2 active area each. In this work, we present the results of the experimental characterization of these photodetector arrays in direct X-ray detection to evaluate the electronics noise, as well as gamma-ray detection with a scintillator. © 2010 Elsevier B.V. All rights reserved.


Castoldi A.,Polytechnic of Milan | Castoldi A.,National Institute of Nuclear Physics, Italy | Guazzoni C.,Polytechnic of Milan | Guazzoni C.,National Institute of Nuclear Physics, Italy | And 8 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

Multi-linear silicon drift detectors (MLSDDs) are good candidates to fulfill simultaneous requirements for 2-D position-sensing and spectroscopy applications. The optimization of their design and performance as 2-D imagers requires a detailed study of timing properties of the charge cloud in the MLSDD architecture. In particular it is important to experimentally determine the dependence of the measured amplitude and time-of-arrival on the photon position of interaction so as to derive the 2D detector response. In this paper we will present a detailed experimental characterization aimed at measuring the detector amplitude response and its timing response. The dependence of charge cloud drift time on precise position of interaction has been measured as a function of detector biasing conditions. © 2010 Elsevier B.V. All rights reserved.


Castoldi A.,Polytechnic of Milan | Guazzoni C.,Polytechnic of Milan | Mezza D.,Polytechnic of Milan | Montemurro G.,Polytechnic of Milan | And 7 more authors.
IEEE Nuclear Science Symposium Conference Record | Year: 2012

In this work we present the experimental qualification of the longitudinal profile of the charge cloud in Multi-Linear Silicon Drift Detectors at high charge levels. This is accomplished by means of a custom-developed deconvolution algorithm, based on the conjugate gradient method that extracts the actual shape of the anode current by deconvolution of the output waveforms of the frontend preamplifier response. We conducted two experimental campaigns, one with a pulsed IR laser system and one with mono-energetic proton bunches which allowed probing the detector response up at high charge levels (up to ∼10 6 electrons). At this level of charge injection Coulomb repulsion and plasma effects start to impact on the charge cloud dynamics and therefore on the detector speed as well as on the spatial resolution. The developed technique provides the true charge cloud profile without any a priori assumptions or model and is a powerful tool for diagnostics of the electron dynamics and for detector qualification in such operating conditions. © 2011 IEEE.


Castoldi A.,Polytechnic of Milan | Guazzoni C.,Polytechnic of Milan | Mezza D.,Polytechnic of Milan | Montemurro G.V.,National Institute of Nuclear Physics, Italy | And 2 more authors.
IEEE Nuclear Science Symposium Conference Record | Year: 2012

We present the design and the experimental characterization of novel topologies of Multi-Linear Silicon Drift Detectors suitable for 1D and 2D position sensing with the aim to extend the potential of silicon drift detector technology to X-ray imaging at high charge injection levels and with faster readout speed. Three detector prototypes has been designed with novel design solutions. The first two prototype are optimized for high charge confinement and for high field operation. The third prototype is designed profiting of a novel technological development for detector production that makes possible self-aligned layout and therefore a finer line-width. The paper will discuss the design features of the Multi-Linear Silicon Drift Detectors prototypes and the results of the experimental campaign with IR laser and with mono-energetic protons. © 2012 IEEE.

Loading MPI Halbleiterlabor collaborators
Loading MPI Halbleiterlabor collaborators