X射线在Au-SiO_2界面剂量增强系数与Au厚度关系的模拟研究

Study of Au Thickness and Dose Enhancement Factor of Au-SiO_2 Interface

用蒙特卡罗（MonteCarlo）方法计算Au—SiOz界面的剂量增强系数（DEF）随能量的变化关系及不同厚度的Au对Au—SiOz界面剂量增强系数的影响。结果表明：界面下的DEF与Au的厚度有关，当Au厚度从1gm增加到9tam，DEF随之增大；当Au厚度超过9tam，随Au厚度增加DEF减小。当x射线能量为10～250keV时，界面附近SiO。一侧存在不同程度的剂量增强，而且在整个能量范围内出现了两个明显的峰值，其中剂量增强系数最大值达40．4。

Using Monte Carlo method, calculated are the relationships between X-ray energy and dose enhancement factor（DEF） at gold-silicon dioxide interface, and the effect of the differ- ent gold thicknesses on the DEF at this interface. The results show that the DEF relates with the gold thickness. The DEF increases with the gold thickness, from 1 μm to 9 μm, and above 9 μm, the DEF decreases with gold thickness. When the X-ray energy ranges from 10 to 250 keV, there are interface dose enhancement in varying degrees with two distinct peaks and the maximum dose enhancement factor is 40.4.