Electron detection with CdTe and GaAs sensors using the charge integrating hybrid pixel detector JUNGFRAU

Abstract Speed, dynamic range, and radiation hardness make hybrid pixel detectors suitable image detectors for diffraction experiments. At synchrotrons and X-ray free electron lasers they are ubiquitous. However, for electron microscopy their spatial resolution is limited by multiple scattering in the sensor layer. In this paper we examine the use of two high Z sensor materials: CdTe and GaAs, as a way to mitigate this problem. The sensors were bonded to a JUNGFRAU readout chip which is a charge integrating hybrid pixel detector developed for use at X-ray free electron lasers. Using in-pixel gain switching, it can detect single particles down to 2 keV while maintaining a dynamic range of 120 MeV/pixel/frame. The characteristics of JUNGFRAU, besides being a capable detector, make it a good tool for sensor characterization since we can measure dark current and energy deposition per pixel. The high Z material shows better spatial resolution than silicon at 200 and 300 keV, however, their practical use with integrating detectors is still limited by material defects.

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Cadmium zinc telluride pixel detectors for high-intensity x-ray imaging at free electron lasers

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/aaf556 ◽

2018 ◽

Vol 52 (8) ◽

pp. 085106 ◽

Cited By ~ 3

Author(s):

M C Veale ◽

C Angelsen ◽

P Booker ◽

J Coughlan ◽

M J French ◽

...

Keyword(s):

Free Electron ◽

High Intensity ◽

Cadmium Zinc Telluride ◽

Zinc Telluride ◽

Free Electron Lasers ◽

X Ray ◽

Pixel Detectors ◽

X Ray Imaging ◽

Cadmium Zinc

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Latest Hybrid Pixel Detectors for increased q/t-resolution in SAXS

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314091177 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C882-C882

Author(s):

Tilman Donath ◽

Benjamin Lüthi ◽

Clemens Schulze-Briese

Keyword(s):

Data Quality ◽

Spatial Resolution ◽

Dynamic Range ◽

Imaging Techniques ◽

Sampling Point ◽

X Rays ◽

Pixel Detector ◽

Pixel Size ◽

Diffractive Imaging ◽

X Ray

The PILATUS was the first Hybrid Pixel Detector available for SAXS. It has transformed data collection by its photon-counting technology, which enables noise-free X-ray detection with high dynamic range and excellent stability at high frame rates. These properties are essential for superior data quality in all scattering experiments, especially for optimal background correction when studying low-concentration samples. Besides optimal data quality at each sampling point, highest resolution is desired in most SAXS experiments both in q-range and in time. The newly developed EIGER pixel detector more than doubles the q-resolution that can be achieved when compared with PILATUS3 for the same sample-to-detector distance. EIGER features a pixel size of only 75 µm (in comparison: PILATUS3 has 172 µm). To characterize the spatial resolution of these detectors, point-spread functions were measured at the PTB laboratory at BESSY II, which show that the resolution is directly proportional to the pixel size with minimal cross talk between neighboring pixels. The EIGER 1M detector allows data acquisition at up to 3'000 frames per second. This enables unprecedented temporal resolution in time-resolved SAXS measurements and increases the speed of novel imaging techniques such as scanning SAXS/WAXS and coherent diffractive imaging applications, allowing images to be recorded faster or with higher spatial resolution. The design of the EIGER detector makes it vacuum compatible. Operation at low X-ray energies and correspondingly large scattering angles is another way of increasing q-resolution and also gives access to the lowest q data near the beam stop. In-vacuum detectors enable measurements with ultra-soft x-rays and thus high q-resolution. Moreover they optimize the data quality in scattering experiments by removing absorption and scatter caused from air and windows. An in-vacuum PILATUS 1M detector has been installed at the BESSY-2 FCM beamline and is applied for SAXS/GI-SAXS measurements at energies from 1.75 to 10 keV. For simultaneous SAXS/WAXS applications covering an even wider q-range, in-vacuum detectors with L-shaped detection surface are under development. These will detect the WAXS signal, while a clearance in the detector permits the direct beam to pass on to a SAXS detector placed at larger distance. These latest detector developments will be presented along with corresponding experimental results.

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Characterisation of the high dynamic range Large Pixel Detector (LPD) and its use at X-ray free electron laser sources

Journal of Instrumentation ◽

10.1088/1748-0221/12/12/p12003 ◽

2017 ◽

Vol 12 (12) ◽

pp. P12003-P12003 ◽

Cited By ~ 4

Author(s):

M.C. Veale ◽

P. Adkin ◽

P. Booker ◽

J. Coughlan ◽

M.J. French ◽

...

Keyword(s):

Free Electron ◽

Free Electron Laser ◽

Dynamic Range ◽

High Dynamic Range ◽

Pixel Detector ◽

X Ray ◽

Laser Sources ◽

High Dynamic

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Prototype characterization of a charge-integration pixel detector readout chip with in-pixel A/D conversion

Journal of Instrumentation ◽

10.1088/1748-0221/17/01/p01003 ◽

2022 ◽

Vol 17 (01) ◽

pp. P01003

Author(s):

M. Li ◽

W. Wei ◽

X. Jiang ◽

S. Cui ◽

J. Zhang ◽

...

Keyword(s):

Free Electron ◽

Free Electron Laser ◽

Dynamic Range ◽

Frame Rate ◽

Functional Verification ◽

Switching Function ◽

Pixel Detector ◽

Long Distance ◽

A Charge ◽

Charge Integration

Abstract HYLITE (High dYmamic range free electron Laser Imaging deTEctor) is a hybrid pixel detector readout chip, which is designed for advanced light sources such as X-ray Free Electron Laser (XFEL) and diffraction-limited storage rings. It is a charge-integration readout chip which has three gains for different dynamic ranges and automatic gain-switching function. The full dynamic range covered by HYLITE is 1 ∼ 104 photons with an energy of 12 keV for each pixel in every shot. In-pixel ADC is designed to achieve front-end digitization and a 10 kHz continuous frame rate. HYLITE0.1 is the first prototype chip for functional verification that was produced in CMOS 0.13 μm technology. It consists of a pixel array with 6 × 12 pixels and a periphery with full standalone operation features. The size of each pixel is 200 μm × 200 μm. Three design variations of pixels with different integrating capacitance and structures were designed to optimize between area and performance. A 10-bit Wilkinson ADC is integrated in each pixel to digitize the outputs of the pre-amplifier. Therefore, analog signal transmission of long distance is avoided and a frame rate of 10 kHz can be achieved. In this paper, we present the design of HYLITE0.1 and the test results of this prototype chip.

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