Study on Neutron Damage Dynamics of Semiconductor Materials

为了从微观角度考察中子损伤效应，人们成功地将高密度集成电路(IC)作为样品用于中子辐照实验。一个CCD图像传感器清楚地测量了硅晶体中中子反应产生的高能粒子的轨迹。(n，p)、(n，α)等中子核反应在径迹上的测量图像数据与TRIM程序的计算结果吻合得很好，这表明利用CCD传感器等精密器件从微观角度对中子损伤进行检测是有效的。通过对其中子损伤常数的实验，得到了DT-DD中子损伤在CCD图像传感器上的相关系数为1.4-1.6。用能谱系统测量了硅表面势垒探测器(Si-SBD)对中子和离子的响应。用基于分子动力学的模拟程序TRIM和MDRANGE对Si-SBD的脉冲高度谱进行了计算，并与实测结果进行了比较。分子动力学模拟程序对Si-SBD在低能区的响应有较好的模拟结果。

In order to examine the neutron damage effects from a microscopic point, highdensity integrated circuits (ICs) such as CCD image sensors were successfully used as samples for neutron irradiation experiments. A CCD image sensor clearly measured tracks of high-energy paticles preduced by neutron reactions in silicon crystal. Measured image data on the tracks by the (n, p), (n, alpha) and other neutron reactions were in good agreement in results calculated with the TRIM code, which suggests that the use of such exquisite devices as CCD sensors are effective in the examination of the neutron damage from a microscopic point. The correlation factor of the DT-DD neutron damage on the CCD image sensors was obtained from experimental results on their neutron damage constants and was found to be 1.4-1.6. This factor approximately agreed with that obtained from the displacement damage calculation.The response of a silicon surface barrier detector (Si-SBD) to neutrons and ions was measured with the energy spectroscopy system. Measured pulse height spectra of a Si-SBD were compared with results calculated with the simulation codes, the well-known TRIM and the MDRANGE based on the molecular dynamics. The molecular dynamics simulation code gave better results on the response of the Si-SBD in lower-energy region.