M. A. Carvajal, J. Banqueri, A. J. Palma, A. M. Lallena, M. Vilches, D. Guirado


A portable dosimeter based on unbiased MOSFET sensor is presented. Its main characteristics are an extended linearity range and a notable thermal drift reduction using a unique p-channel MOSFET (pMOS) unbiased during the irradiation period, allowing the location of the sensor without wires for patient comfort and easy-to-use. Both features have been obtained with novel procedures of dose reading and signal processing applied to low-cost commercial pMOS. In this work, a full description of the electronics of the dosimetry system and the signal processing techniques are drawn. The system has been tested with photons from 60Co and the complete technical specifications have been obtained. Among them, we can emphasize: i) dose sensitivity of around 25 mV/Gy; ii) linearity range of more than 50 Gy, with intermediate calibration each 15 Gy, for each sensor; iii) thermal drift below 3 mGy/ºC; iv) resolution below 1cGy; and v) total uncertainty of ± 9 mGy in the temperature range from 19 ºC to 36 ºC . We believe that the proposed dosimeter could be a novel and feasible low-cost alternative to previous commercial dosimetry systems for radiotherapy monitoring in clinical applications.


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Paper Citation

in Harvard Style

Carvajal M., Banqueri J., Palma A., Lallena A., Vilches M. and Guirado D. (2011). PORTABLE DOSIMETER WITH MOSFET SENSOR FOR RADIOTHERAPY MONITORING . In Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2011) ISBN 978-989-8425-37-9, pages 23-29. DOI: 10.5220/0003128100230029

in Bibtex Style

author={M. A. Carvajal and J. Banqueri and A. J. Palma and A. M. Lallena and M. Vilches and D. Guirado},
booktitle={Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2011)},

in EndNote Style

JO - Proceedings of the International Conference on Biomedical Electronics and Devices - Volume 1: BIODEVICES, (BIOSTEC 2011)
SN - 978-989-8425-37-9
AU - Carvajal M.
AU - Banqueri J.
AU - Palma A.
AU - Lallena A.
AU - Vilches M.
AU - Guirado D.
PY - 2011
SP - 23
EP - 29
DO - 10.5220/0003128100230029