基于镍-63硅基辐伏能量转换结构初探

针对辐射伏特效应同位素微电池研究中所面临的主要问题——辐伏转换效率提高与辐射损伤 这一相互制约的矛盾体,利用单晶硅低能电子辐照感生缺陷行为研究,结合两种PIN结构的 电学性能测试,提出I区掺杂浓度为2×10¹² cm^-3的P⁺I (N^-) N⁺器件符合 P, N型硅辐射损伤效应预测结果.并以此为原型器件进行⁶³Ni辐照在线输出特性测试, 通过与Wisconsin大学实验数据比较,对影响能量转换效率低下的主要因素进行了分析, 考虑主要从器件采用三维PIN结结构;增大耗尽层能量沉积比重; I (N^-)区宽度与沉积深度匹配; 控制漏电流在皮安量级等方面提高能量转换效率,据此对硅基能量转换结构进行设计, 最终确定PIN多孔结构、辐射源厚度、掺杂浓度、耗尽层宽度等结构参数,完成换能结构优化.

Investigation of a energy conversion silicon chip based on 63Ni radio-voltaic effect

Aiming at the main problem encountered in the research of radioisotope microbattery based on β radio-voltaic effect-enhancement of energy transfer efficiency and radiation damage as mutually constraining sides of a contradiction, an investigation of radiation-induced defects in different silicon wafers by low-energy electron irradiation was carried out and the electrical characteristic measurement for two types of PIN structures indicated that P⁺I (N^-) N⁺ device in I zone with a dopant concentration of 2× 10¹² cm^-3 agreed with the predicted result of P, N type silicon radiation damage effect. This was then taken as the prototype device, on which test of ⁶³Ni radiation output characteristics was performed. The test result was compared with the experimental data of Wisconsin University and the major factors causing low energy transfer efficiency were analysed. Adoption of three-dimensional PIN junction structure, increasing the proportion of energy deposition in depletion region, matching I (N^-) zone width and deposition depth and controlling the leak current under an order of magnitude of Picoampere were considered to enhance the energy transfer efficiency, based on which energy transfer structure was designed and ultimately structure parameters such as multi-hole PIN structure, radiation source thickness, depletion region width were determined, thus the energy transfer structure optimization was accomplished.