Characteristics of microSilicon diode detector for electron beam dosimetry
Characteristics of microSilicon diode detector for electron beam dosimetry
复制标题
电子束剂量测定用微硅二极管探测器的特点
DOI：
10.1093/jrr/rrab085
复制
发表时间：
2021
影响因子：
2
通讯作者：
Ogawa K
中科院分区：
文献类型：
--
作者：
Akino Y;Das IJ;Fujiwara M;Kaneko A;Masutani T;Mizuno H;Isohashi F;Suzuki O;Seo Y;Tamari K;Ogawa K
microSilicon™（PTW型60023）是继二极管E（型号60017，PTW）之后的一种新型无屏蔽二极管检测器，其特征在于用于电子束剂量测定，并与其他检测器进行比较。使用microSilicon、Diode E和microDiamond合成单晶金刚石探测器测量TrueBeam直线加速器产生的电子束。通过在空气和水中采集的数据，测量了微硅的位置精度。评价了百分比深度剂量（PDD）、偏心比（OCR）、剂量-反应线性、剂量率依赖性和锥因子。的PDD进行了比较，使用PPC 40平面平行电离室测量的数据。最大剂量的50%和90%深度的最大变化以及所有探测器和能量之间的实际深度的最大变化为0.9mm。韧致辐射剂量在所有探测器和能量之间的最大变化在0.3%以内。OCR显示出良好的一致性在1%以内的平坦和尾部区域。微硅探测器显示出与微金刚石相似的半影宽度，而二极管E显示出最陡的半影形状。所有探测器均表现出良好的剂量响应线性和剂量率稳定性;只有二极管E表现出对数剂量率依赖性。对于所有能量和锥体尺寸，使用microSilicon测量的锥体系数在±1%范围内。我们证明了微硅的特性适合于电子束剂量学。微硅探测器可以是一个很好的替代电子束剂量学在提供一个适当的PDD曲线没有校正，高空间分辨率的OCR测量和锥因子。
A microSilicon™ (PTW type 60023), a new unshielded diode detector succeeding Diode E (model 60017, PTW), was characterized for electron beam dosimetry and compared with other detectors. Electron beams generated from a TrueBeam linear accelerator were measured using the microSilicon, Diode E, and microDiamond synthetic single-crystal diamond detector. Positional accuracy of microSilicon was measured by data collected in air and water. The percent depth dose (PDD), off-center ratio (OCR), dose–response linearity, dose rate dependence, and cone factors were evaluated. The PDDs were compared with data measured using a PPC40 plane-parallel ionization chamber. The maximum variations of depth of 50% and 90% of the maximum dose, and practical depth among all detectors and energies were 0.9 mm. The maximum variations of the bremsstrahlung dose among all detectors and energies were within 0.3%. OCR showed good agreement within 1% for the flat and tail regions. The microSilicon detector showed a penumbra width similar to microDiamond, whereas Diode E showed the steepest penumbra shape. All detectors showed good dose–response linearity and stability against the dose rate; only Diode E demonstrated logarithmic dose rate dependency. The cone factor measured with microSilicon was within ±1% for all energies and cone sizes. We demonstrated that the characteristics of microSilicon is suitable for electron beam dosimetry. The microSilicon detector can be a good alternative for electron beam dosimetry in terms of providing an appropriate PDD curve without corrections, high spatial resolution for OCR measurements and cone factors.