TY - JOUR
T1 - Dose rate effects on the thermoluminescence properties of MWCVD diamond films
AU - Gastélum, S.
AU - Cruz-Zaragoza, E.
AU - Meléndrez, R.
AU - Chernov, V.
AU - Barboza-Flores, M.
N1 - Funding Information:
The authors are indebted to Dr. B. Gan for growing the samples and Prof. C. Furetta for enthusiastic and enlightening discussions. We acknowledge financial support from the Oficina de Colaboración Interinstitucional UNAM, SEP and Conacyt grants No. 36521, 37641 and 32069.
PY - 2007/7
Y1 - 2007/7
N2 - Synthetic CVD diamond, being non-toxic and tissue equivalent, has been proposed as a ionizing radiation passive dosimeter with relevant applications in radiotherapy and clinical dosimetry. In the present work, the thermoluminescence (TL) properties of microwave-assisted chemical vapor deposition (MWCVD) diamond, 6m thick film grown on (100) silicon substrates, were studied after room temperature -irradiation for 2.4, 3.1, 5.94, 13.1, 20.67, 43.4 and 81.11Gy min-1 dose rates in the range of 0.05-10kGy. At fixed irradiation dose the TL efficiency increases as the dose rate increases. As the dose increases the peak temperature at the maximum intensity of the TL glow curve is shifted about 10K degrees toward the lower temperature side. The TL glow curve shape resembles first-order kinetics for low-radiation doses and second-order kinetics for higher doses. Linear dose behavior was found for doses below 200Gy and supralinear for higher doses; respectively, with a significant dependence on the dose rate, reaching saturation for higher doses around 2.0kGy. Due to the dose rate dependence of the TL properties of the CVD diamond sample, it is necessary to take these effects into consideration for dosimetric applications involving synthetic CVD diamond.
AB - Synthetic CVD diamond, being non-toxic and tissue equivalent, has been proposed as a ionizing radiation passive dosimeter with relevant applications in radiotherapy and clinical dosimetry. In the present work, the thermoluminescence (TL) properties of microwave-assisted chemical vapor deposition (MWCVD) diamond, 6m thick film grown on (100) silicon substrates, were studied after room temperature -irradiation for 2.4, 3.1, 5.94, 13.1, 20.67, 43.4 and 81.11Gy min-1 dose rates in the range of 0.05-10kGy. At fixed irradiation dose the TL efficiency increases as the dose rate increases. As the dose increases the peak temperature at the maximum intensity of the TL glow curve is shifted about 10K degrees toward the lower temperature side. The TL glow curve shape resembles first-order kinetics for low-radiation doses and second-order kinetics for higher doses. Linear dose behavior was found for doses below 200Gy and supralinear for higher doses; respectively, with a significant dependence on the dose rate, reaching saturation for higher doses around 2.0kGy. Due to the dose rate dependence of the TL properties of the CVD diamond sample, it is necessary to take these effects into consideration for dosimetric applications involving synthetic CVD diamond.
KW - CVD diamond films
KW - Dose rate effects
KW - Dosimetry
KW - Gamma radiation
KW - Thermoluminescence
UR - http://www.scopus.com/inward/record.url?scp=34548303536&partnerID=8YFLogxK
U2 - 10.1080/10420150701470704
DO - 10.1080/10420150701470704
M3 - Artículo
AN - SCOPUS:34548303536
SN - 1042-0150
VL - 162
SP - 587
EP - 595
JO - Radiation Effects and Defects in Solids
JF - Radiation Effects and Defects in Solids
IS - 7-8
ER -