8th International Workshop on Semiconductor Pixel Detectors for Particles and Imaging.

The EIGER detector systems

Non in programma

20m

Sestri Levante

contributed paper

Relatore

Dr. Gemma Tinti (Paul Scherrer Institute)

Descrizione

EIGER is a single photon counting hybrid pixel detector developed at the Paul Scherrer Institute (PSI) for synchrotron applications. The pixel size is 75x75 um^2 and it features noise as low as 70 e^- equivalent noise charge RMS (depending on settings) and a very high frame rate (up to 24 kHz). Each pixel has a counter which can be configured in 4, 8 or 12 bit mode. A larger dynamic range of 32 bits can be obtained by splitting the acquisition into short sub-frames and summing them on the readout boards. The minimum dead time between frames is 3 us thanks to the double buffering capabilities of the counter. Large area EIGER detectors are being produced by tiling single modules. A single module consists of a 8x4 cm^2 silicon sensor bump bonded to 4x2 readout chips, for a total of 0.5 Mpixels. The largest of the systems in production at PSI is a 9~Mpixel detector for the coherent small angle X-ray scattering (cSAXS) beamline at the Swiss Light Source Synchrotron. The very high frame rate capability is conserved for multi-module systems due to fully parallel data processing. The count rate capabilities are 200-500 kHz/pixel at 90% linearity of the counter versus the incident photon flux. Rate corrections can be applied on-board before the sub-frame summation to compensate for fast varying pile-up rates. The on-board corrections restore the linearity up to at least 1.2 MHz/pixel incident rate. Performance of the detector, calibration and operational challenges of the large systems will be presented. EIGER can also be used to detect electrons: characterization of the detector performances with low energy electrons (8-20 keV) and medium energy (>100 keV) has been performed. Results will be presented as well as plans to optimize the detector for electron detection towards the use of EIGER in photo-emission electron microscopes and transmission electron microscopes.