Matches in SemOpenAlex for { <https://semopenalex.org/work/W2096119945> ?p ?o ?g. }
- W2096119945 abstract "This thesis details an investigation of the suitability of commercially-available single crystal and polycrystalline diamond films made via chemical vapor deposition (CVD) that were not studied previously for use in radiotherapy dosimetry. Novel sandwich-type detectors were designed and constructed to investigate the dosimetric response of diamond films under clinical conditions. Relatively inexpensive diamond films were obtained from three manufacturers: Diamonex, Diamond Materials GmbH and Element Six. Spectrophotometry, Raman spectroscopy and bulk conductivity studies were used to characterize these films and correlate crystalline quality with detector performance. Novel detectors were designed and constructed to investigate detectors under clinical conditions, including Perspex encapsulations and PCBs to minimize fluence perturbations. The dosimetric response of these diamond detectors was examined using a 6 MV beam from a Varian Clinac 600C linear accelerator. Diamond detectors were evaluated by measuring a number of response characteristics.Polycrystalline CVD diamond films from Diamonex (100, 200, 400-μm thicknesses) were considered unsuitable for dosimetric applications due to their lack of stability, low sensitivity, high leakage currents, high priming dose and dependence on dose rate. High-quality polycrystalline diamond films from Diamond Materials (100, 200, 400-μm thicknesses) displayed characteristics that varied with film thickness. A 100-μm film featured slow response dynamics and high priming doses. Thicker films featured suitable dosimetric characteristics, e.g. negligible leakage currents, low priming doses, fast response dynamics and good sensitivity with small sensitive volumes. Element Six single crystal CVD diamond films (500-μm thicknesses) with small sensitive volumes (0.39 mm³) exhibited suitable characteristics for dosimetry. These films showed negligible leakage currents (< 1.25 pA), low priming doses (1–10 Gy), quick response dynamics, high sensitivity (47–230 nC Gy⁻¹) and were weakly dependent on dose rate and directional dependence (±1%). A relatively inexpensive single crystal CVD diamond film from Element Six that exhibited high sensitivity (230 nC Gy⁻¹ at 0.5 V μm⁻¹), amongst other favourable characteristics, was selected for further analyses. An appropriate operating voltage was determined before further clinically relevant measurements could be conducted. This included how changes in an applied electric field affected detector response, and determined whether an optimal operating voltage could be realized within the parameters of conventional instrumentation used in radiation therapy. The results of this study indicated a preference towards using 62.5 V (at ~0.13 V μm⁻¹) out of a range of 30.8–248.0 V for temporal response as required for modulated beams due to its minimal rise time (2 s) and fall time (2 s) yet sufficient sensitivity (37 nC Gy⁻¹) and weak dependence on polarity (±1.5%). Investigations were then performed on the same diamond detector to…" @default.
- W2096119945 created "2016-06-24" @default.
- W2096119945 creator A5060250706 @default.
- W2096119945 date "2010-01-01" @default.
- W2096119945 modified "2023-09-23" @default.
- W2096119945 title "Development of a Prototype Synthetic Diamond Detector for Radiotherapy Dosimetry" @default.
- W2096119945 cites W1242424520 @default.
- W2096119945 cites W147319338 @default.
- W2096119945 cites W1484334610 @default.
- W2096119945 cites W1485096288 @default.
- W2096119945 cites W1493604621 @default.
- W2096119945 cites W1516817720 @default.
- W2096119945 cites W1526218031 @default.
- W2096119945 cites W1535211234 @default.
- W2096119945 cites W1535898099 @default.
- W2096119945 cites W1535939676 @default.
- W2096119945 cites W1569356849 @default.
- W2096119945 cites W1605467703 @default.
- W2096119945 cites W1606049780 @default.
- W2096119945 cites W1641551628 @default.
- W2096119945 cites W1964529543 @default.
- W2096119945 cites W1964998747 @default.
- W2096119945 cites W1965519298 @default.
- W2096119945 cites W1966642079 @default.
- W2096119945 cites W1966857337 @default.
- W2096119945 cites W1967552337 @default.
- W2096119945 cites W1967798147 @default.
- W2096119945 cites W1968567699 @default.
- W2096119945 cites W1969325923 @default.
- W2096119945 cites W1970794371 @default.
- W2096119945 cites W1970924615 @default.
- W2096119945 cites W1970926590 @default.
- W2096119945 cites W1971488612 @default.
- W2096119945 cites W1971540314 @default.
- W2096119945 cites W1971966604 @default.
- W2096119945 cites W1974292779 @default.
- W2096119945 cites W1974461554 @default.
- W2096119945 cites W1977920155 @default.
- W2096119945 cites W1978191318 @default.
- W2096119945 cites W1978865860 @default.
- W2096119945 cites W1980268171 @default.
- W2096119945 cites W1980423700 @default.
- W2096119945 cites W1980462610 @default.
- W2096119945 cites W1981167949 @default.
- W2096119945 cites W1981877939 @default.
- W2096119945 cites W1982020568 @default.
- W2096119945 cites W1982710927 @default.
- W2096119945 cites W1983185290 @default.
- W2096119945 cites W1983492209 @default.
- W2096119945 cites W1985288941 @default.
- W2096119945 cites W1986409491 @default.
- W2096119945 cites W1987150312 @default.
- W2096119945 cites W1987294590 @default.
- W2096119945 cites W1987485906 @default.
- W2096119945 cites W1988458064 @default.
- W2096119945 cites W1989752136 @default.
- W2096119945 cites W1990210557 @default.
- W2096119945 cites W1991501080 @default.
- W2096119945 cites W1992041283 @default.
- W2096119945 cites W1993962157 @default.
- W2096119945 cites W1994065290 @default.
- W2096119945 cites W1994557130 @default.
- W2096119945 cites W1994568329 @default.
- W2096119945 cites W1995013069 @default.
- W2096119945 cites W1995837699 @default.
- W2096119945 cites W1998585582 @default.
- W2096119945 cites W1998782611 @default.
- W2096119945 cites W1999438941 @default.
- W2096119945 cites W2000563766 @default.
- W2096119945 cites W2001311595 @default.
- W2096119945 cites W2001434079 @default.
- W2096119945 cites W2002489286 @default.
- W2096119945 cites W2003306477 @default.
- W2096119945 cites W2003443926 @default.
- W2096119945 cites W2004598119 @default.
- W2096119945 cites W2004947669 @default.
- W2096119945 cites W2005043149 @default.
- W2096119945 cites W2006610647 @default.
- W2096119945 cites W2007367508 @default.
- W2096119945 cites W2008504693 @default.
- W2096119945 cites W2008700492 @default.
- W2096119945 cites W2009121933 @default.
- W2096119945 cites W2009777277 @default.
- W2096119945 cites W2011724134 @default.
- W2096119945 cites W2012325715 @default.
- W2096119945 cites W2012662343 @default.
- W2096119945 cites W2012682411 @default.
- W2096119945 cites W2012877757 @default.
- W2096119945 cites W2012931237 @default.
- W2096119945 cites W2013366981 @default.
- W2096119945 cites W2015354002 @default.
- W2096119945 cites W2015851130 @default.
- W2096119945 cites W2016764100 @default.
- W2096119945 cites W2017511987 @default.
- W2096119945 cites W2019013006 @default.
- W2096119945 cites W2019119558 @default.
- W2096119945 cites W2019333274 @default.
- W2096119945 cites W2019659451 @default.
- W2096119945 cites W2019925037 @default.
- W2096119945 cites W2020493657 @default.