The LAMBDA photon-counting pixel detector and high-Z sensor development

• Published in: Journal of instrumentation Vol. 9; no. 12; p. C12026
• Main Authors: Pennicard, D, Smoljanin, S, Struth, B, Hirsemann, H, Fauler, A, Fiederle, M, Tolbanov, O, Zarubin, A, Tyazhev, A, Shelkov, G, Graafsma, H
• Format: Journal Article
• Language: English
• Published: 01.12.2014
• Subjects: Arrays; Detectors; Gallium arsenide; High speed; Pixels; Sensors; Synchrotrons; X-rays
• ISSN: 1748-0221; 1748-0221
• DOI: 10.1088/1748-0221/9/12/C12026

Many X-ray experiments at third-generation synchrotrons benefit from using single-photon-counting detectors, due to their high signal-to-noise ratio and potential for high-speed measurements. LAMBDA (Large Area Medipix3-Based Detector Array) is a pixel detector system based on the Medipix3 readout chip. It combines the features of Medipix3, such as a small pixel size of 55 [mu]m and flexible functionality, with a large tileable module design consisting of 12 chips (1536 x 512 pixels) and a high-speed readout system capable of running at 2000 frames per second. To enable high-speed experiments with hard X-rays, the LAMBDA system has been combined with different high-Z sensor materials. Room-temperature systems using GaAs and CdTe systems have been produced and tested with X-ray tubes and at synchrotron beamlines. Both detector materials show nonuniformities in their raw image response, but the pixel yield is high and the uniformity can be improved by flat-field correction, particularly in the case of GaAs. High-frame-rate experiments show that useful information can be gained on millisecond timescales in synchrotron experiments with these sensors.