Characterisation of a PERCIVAL monolithic active pixel prototype using synchrotron radiation

• Published in: Journal of instrumentation Vol. 11; no. 2; p. C02090
• Main Authors: Correa, J., Bayer, M., Göttlicher, P., Lange, S., Marras, A., Niemann, M., Reza, S., Shevyakov, I., Smoljanin, S., Tennert, M., Xia, Q., Viti, M., Wunderer, C.B., Zimmer, M., Dipayan, D., Guerrini, N., Marsh, B., Sedgwick, I., Turchetta, R., Cautero, G., Giuressi, D., Khromova, A., Pinaroli, G., Menk, R., Stebel, L., Fan, R., Marchal, J., Pedersen, U., Rees, N., Steadman, P., Sussmuth, M., Tartoni, N., Yousef, H., Hyun, H.J., Kim, K., Rah, S., Graafsma, H.
• Format: Journal Article
• Language: English
• Published: 29.02.2016
• Subjects: CMOS; Instrumentation for FEL; Photons; Pixels; Prototypes; Sensors; Soft x-rays; Solid state detectors; Synchrotron radiation; X-ray detectors
• ISSN: 1748-0221; 1748-0221
• DOI: 10.1088/1748-0221/11/02/C02090

PERCIVAL ("Pixelated Energy Resolving CMOS Imager, Versatile And Large") is a monolithic active pixel sensor (MAPS) based on CMOS technology. Is being developed by DESY, RAL/STFC, Elettra, DLS, and PAL to address the various requirements of detectors at synchrotron radiation sources and Free Electron Lasers (FELs) in the soft X-ray regime. These requirements include high frame rates and FELs base-rate compatibility, large dynamic range, single-photon counting capability with low probability of false positives, high quantum efficiency (QE), and (multi-)megapixel arrangements with good spatial resolution. Small-scale back-side-illuminated (BSI) prototype systems are undergoing detailed testing with X-rays and optical photons, in preparation of submission of a larger sensor. A first BSI processed prototype was tested in 2014 and a preliminary result-first detection of 350eV photons with some pixel types of PERCIVAL-reported at this meeting a year ago. Subsequent more detailed analysis revealed a very low QE and pointed to contamination as a possible cause. In the past year, BSI-processed chips on two more wafers were tested and their response to soft X-ray evaluated. We report here the improved charge collection efficiency (CCE) of different PERCIVAL pixel types for 400eV soft X-rays together with Airy patterns, response to a flat field, and noise performance for such a newly BSI-processed prototype sensor.