Abstract In the present work, the radioactive solution of 0.10 Molar 35S-aqua regia with half-life of 86.35 ± 0.17 days and specific activity of 519 Ci/cm3 was considered as a source. First, the beta spectrum of 35S was calculated. Then, by MCNPX code the effects of factors such as radius variation, height variation, type of substrate and type of side surface coating on the source efficiency were investigated. Also, by discussing the effect of minority carrier diffusion length, junction depth, geometric shape of P-N junction and doping concentration on the property of betavoltaic batteries, the present work concluded that the best parameters for betavoltaic batteries are the use of silicon and the radioactive solution of 0.10 Molar 35S-aqua regia, thickness of the titanium coating around the radioactive solution of 0.1 µm and junction depth of 0.2 µm, spherical P-N junction, Nd (doping concentration of N-type region) = 1.000 × 1017 cm−3 and Na (doping concentration of P-type region) = 4.500 × 1016 cm−3. Under these parameters the short circuit current, open circuit voltage and energy conversion efficiency are 0.926nA, 0.233 V and 2.513%, respectively. Also, the amounts of the short circuit current, open circuit voltage, and energy conversion efficiency were calculated for the titanium coating with thicknesses 0.5, 1, 2, and 10 µm. It is not easy to build the titanium coating with a thickness of 0.1 µm. So, in the manufacturing process, the titanium coating with a thickness 10 µm can be used. Since the relationship between battery parameters and activity is linear. To offset the amounts of the short circuit current, open circuit voltage and energy conversion efficiency, the activity needs to be increased about 6.521 times.

中文翻译：

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微尺寸Si-35S贝塔伏特液体核电池的设计与优化以构建

摘要 在目前的工作中，以0.10 摩尔35S-王水的放射性溶液为源，其半衰期为86.35±0.17 天，比活度为519 Ci/cm3。首先，计算35S的β谱。然后，通过MCNPX代码研究了半径变化、高度变化、基材类型和侧面涂层类型等因素对源效率的影响。此外，通过讨论少数载流子扩散长度、结深度、PN结几何形状和掺杂浓度对贝塔伏特电池性能的影响，目前的工作得出结论，贝塔伏特电池的最佳参数是使用硅和放射性溶液0.10 摩尔 35S-王水，放射性溶液周围的钛涂层厚度为 0.1 µm，结深为 0。2 µm，球形 PN 结，Nd（N 型区域的掺杂浓度）= 1.000 × 1017 cm-3 和 Na（P 型区域的掺杂浓度）= 4.500 × 1016 cm-3。在这些参数下，短路电流、开路电压和能量转换效率分别为 0.926nA、0.233 V 和 2.513%。此外，还计算了厚度为 0.5、1、2 和 10 µm 的钛涂层的短路电流、开路电压和能量转换效率的量。构建厚度为 0.1 µm 的钛涂层并不容易。因此，在制造过程中，可以使用厚度为 10 µm 的钛涂层。由于电池参数和活性之间的关系是线性的。为了抵消短路电流、开路电压和能量转换效率的量，