对于单板钴源而言，现有源棒排列优化方法都针对辐射加工，难以满足电子学器件耐辐照考核实验对剂量场均匀性较高的要求。通过建立数学模型，对基于改进型贪心算法进行求解，实现了源棒排列优化。算法采用贪心算法策略，以使参考辐照面剂量率不均匀度最小为约束条件来确定源棒位置；参考经验法来限制求解空间，利用枚举法改善初始条件、放置顺序对排源结果的影响，以增大算法的全局搜索能力。算例结果表明：针对耐辐照考核实验，获得了参考面剂量率不均匀度≤1.02条件下的源棒排列，满足使用要求，排源效果优于经验法，效率提高约100倍；针对辐射加工，排源效果、效率与已有基于贪心算法和模拟植物生长算法的优化方法相当。本文排源方法既能用于耐辐照考核实验又可适用于辐射加工。%Background: Concerning radiation hardness assurance testing of microelectronic devices, there is rigorous requirement for the dose rate uniformity of irradiation field. With existing methods, the source rods of single-plate irradiation facility cannot be configured properly in the source plaque, which consequently form the prospected irradiation field.Purpose: This study aims to construct a new method to realize the optimal deployment of source rods and meet the requirements of radiation hardness assurance testing.Methods: The new method was realized by constructing mathematical model and designing improved greedy algorithm. The algorithm mainly contained three aspects. First of all, there was the thought of existing greedy algorithm, which is to determine position of source rods with the objective function defined by uniformity of dose rate at the reference points. In addition, the position of source rods was constricted according to empirical method. Finally, the global searching ability was improved by using enumeration technique.Results: For radiation hardness assurance testing, this method was able to construct irradiation field with dose rate uniformity no more than 1.02, and it was better and 100 times faster than the empirical method. As for irradiation process, the dose rate uniformity and efficiency obtained by this new method is similar to the existing methods such as greedy algorithm and plant growth simulation algorithm.Conclusion: This new method is effective for both the radiation hardness assurance testing and the irradiation process applications.
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