Comparison between bulk micromachined and CMOS detectors for X-ray measurements

This paper compares two x-ray detectors fabricated using two different technologies: one is based on a bulk micromachined silicon photodetector and the other is based on a standard CMOS photodetector. The working principle of the two detectors is similar: a scintillating layer of CsI:Tl is placed above the photodetector, so the x-rays are first converted into visible light (560 nm) which is then converted into an electrical signal by the photodetector. The different aspects of the fabrication and the experimental results of both x-ray detectors are presented and discussed.This work was supported by The Foundation of Science and Technology, Portugal, FCT-CTM/POCTI/33751/1999; Grant-BD SFRH/BD/1296/2000