Abstract
The results obtained with a standard float zone (FZ) silicon diode, processed at the Helsinki Institute of Physics, used as on-line diagnostic X-ray dosimeter are described in this work. The device was connected in the short-circuit current mode to the input of an integrating electrometer. The response repeatability and the current sensitivity coefficient of the diode were measured with diagnostic X-ray beams in the range of 40-80 kV. The dose-response of the device, evaluated from 10 mGy up to 500 mGy, was linear with high charge sensitivity. Nevertheless, significant energy dependence was observed in the charge sensitivity of FZ device for energies below 70 kV. The dosimetric characteristics of this FZ diode were compared to those of an XRA-50 commercial Si diode, specially designed to X-ray dosimetry. The results obtained with the FZ diode evidenced that it can be an alternative choice for diagnostic X-ray dosimetry, although it needs to be calibrated for individual X-ray beam energies. The studies of long-term stability and the radiation hardness of these diodes are under way.
Highlights
Semiconductor devices have been used for photon and electron beam dosimetry mainly in the field of radiation protection, medical imaging and radiation therapy [1,2,3]
Previous results obtained in our laboratory using similar radiation-hard Si diodes in radiation dosimetry [9, 10] motivated us to investigate the response of an n-type float zone (FZ) d iode for on-line diagnostic X-ray dosimetry
The dynamic current response of the rad-hard FZ diode and the commercial XRA-50 diode was investigated with irradiation energies of the X-ray beam from 40 kV to 80 kV and the dose rate range from 9.9 mGy/min to 42.8 mGy/min
Summary
Semiconductor devices have been used for photon and electron beam dosimetry mainly in the field of radiation protection, medical imaging and radiation therapy [1,2,3]. Si devices demands a periodic recalibration of the dosimeter related to the sensitivity decay as a function of the accumulated dose. This drop in sensitivity due to radiation damage imposes constraint on the wides pread use of ordinary silicon diodes as dosimeters [4,5,6,7]. Previous results obtained in our laboratory using similar radiation-hard (rad-hard) Si diodes in radiation dosimetry [9, 10] motivated us to investigate the response of an n-type float zone (FZ) d iode for on-line diagnostic X-ray dosimetry. The dosimetric characteristics of this FZ diode were compared to those of an XRA-50 commercial photodiode, specially designed for X-ray dosimetry [11]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
