β辐射伏特效应电池内建电场厚度设计

计算了放射源在半导体中沿厚度方向的能量沉积,并以此计算β辐射伏特效应电池的理想短路电流。通过对比实测短路电流和理想短路电流可以得到β辐射伏特效应电池PN结内建电场的扩散长度。在上述基础上,本文给出了β辐射伏特效应电池内建电场厚度设计原则： 放射源在半导体中能量沉积厚度和PN结内建电场中载流子的扩散长度两者中较小的应作为β伏特效应电池内建电场厚度设计值,如果沉积厚度远远大于载流子扩散长度,则说明多结结构较适合该类β伏特效应电池果,多结的结数应约为沉积厚度与载流子扩散长度的比。

Built-in electric field thickness design for betavoltaic batteries

Isotope source energy deposition along the thickness direction of a semiconductor is calculated, based upon which an ideal short current is evaluated for betavoltaic batteries. Electron-hole pair recombination and drifting length in a PN junction built-in electric field are extracted by comparing the measured short currents with the ideal short currents. A built-in electric field thickness design principle is proposed for betavoltaic batteries: after measuring the energy deposition depth and the carrier drift length, the shorter one should then be chosen as the built-in electric field thickness. If the energy deposition depth is much larger than the carrier drift length, a multijunction is preferred in betavoltaic batteries and the number of the junctions should be the value of the deposition depth divided by the drift length.