Multispectral photon-counting for medical imaging and beam characterization - A project review

Stefanie Kirschenmann, Mihaela Bezak, Shudhashil Bharthuar, Erik Brücken, Muhammad Emzir, Maria Golovleva, Akiko Gädda, Matti Kalliokoski, Aneliya Karadzhinova-Ferrer, Ahti Karjalainen, Pirkitta Koponen, Nikita Kramarenko, Panja Luukka, Jennifer Ott, Henri Petrow, Teemu Siiskonen, Simo Särkkä, Joonas Samuli Tikkanen, Raimo Turpeinen, Alexander Winkler

Research output: Contribution to journalArticleScientificpeer-review


Central focus of the MPMIB project – funded via the Academy of Finland’s RADDESS 2018–2021 programme – has been research towards a next-generation radiation detection system operating in a photon-counting (PC) multispectral mode: The extraction of energy spectrum per detector pixel data will lead to better efficacy in medical imaging with ionizing radiation. Therefore, it can be an important asset for diagnostic imaging and radiotherapy, enabling better diagnostic outcome with lower radiation dose as well as more versatile characterization of the radiation beam, leading for example to more accurate patient dosimetry. We present our approach of fabricating direct-conversion detectors based on cadmium telluride (CdTe) semiconductor material hybridized with PC mode capable application-specific integrated circuits (ASICs), and will give a review on our achievements, challenges and lessons learned. The CdTe crystals were processed at Micronova, Finland’s national research infrastructure for micro- and nanotechnology, employing techniques such as surface passivation via atomic layer deposition, and flip chip bonding of processed sensors to ASIC. Although CdTe has excellent photon radiation absorption properties, it is a brittle material that can include large concentrations of defects. We will therefore also emphasize our quality assessment of CdTe crystals and processed detectors, and present experimental data obtained with prototype detectors in X-ray and Co-60 beams at a standards laboratory
Original languageEnglish
Article number167043
JournalNuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment
Number of pages5
Publication statusPublished - 11 Sept 2022
MoE publication typeA1 Journal article-refereed
Event16th Vienna Conference on Instrumentation (VCI) -
Duration: 21 Feb 202225 Feb 2022

Fields of Science

  • 114 Physical sciences
  • Detectionofdefects
  • Materialsforsolid-statedetectors
  • Medicalimaging
  • Photoncountingdetectors

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