MOS结构的质子辐照效应

利用微分电容法和禁带中央电压漂移技术,研究了铝栅MOS结构质子辐照诱发的新生界面陷阱和氧化层陷阱结构。结果表明,质子辐照所诱发的新生界面陷阱和氧化层陷阱随质子能量和剂量的增加而增加。用H~+二级过程模型和计算机模拟定性解释了实验结果。     

强流电子束在薄靶中的能量沉积

由测量飞散离子判定了强流电子束在薄靶中的能量沉积。飞散离子能量的测定是根据飞行时间法及阻滞电压测量。结果表明,对于高Z靶,能量沉积与经典的能量沉积相符合;对低Z靶,能量沉积比经典的能量沉积高一些。     

计算脉冲电子束辐照下能量沉积剖面的新方案

脉冲电子束辐照材料试验研究中,束流电子具有不同的速度和角度分布。但数值模拟计算一般都考虑电子束垂直入射靶材料,这可能导致数值计算结果与试验结果不符。针对该问题,提出了一种计算电子束辐照下能量沉积剖面的新方案,利用MCNP(Monte Carlo N Particle Transport Code)软件对铝、铜、钽金属材料在电子束辐照下的能量沉积进行模拟,分析了电子束垂直入射与带有角度分布入射时能量沉积的差异,为解释电子束辐照试验测量数据与理论计算结果之间的差异提供了依据。     

强流电子束在薄靶中能量沉积的模拟计算

一、引言美、日等国发表过利用强流相对论电子束打靶的实验与理论工作。本文采用MonteCarlo方法模拟计算强流电子束在薄靶物质中的能量沉积。目的是配合中国原子能科学研究院17室强流电子束加速器的物理实验,提供一些理论解释。     

氧化锡气体传感器的电子束辐照效应

There are many traditional ways to improve sensitivity and selectivity of semiconductor gas sensors, such as metal ions adulteration and surface modification. In this paper 1.75 MeV electron beam was used to modify surface structure of tin dioxide gas sensors, and the gas sensing characteristics were studied. Results showed that the sensitivity and selectivity of SnO2 sensors were improved after the electron beam irradiation.     

环氧树脂电子束辐射效应研究

为了研究不同结构的环氧树脂在电子束辐射条件下的辐射化学行为及其对环氧树脂辐射固化行为与性能的影响。通过对环氧树脂电子束辐射前后的粘度变化、加热失重率以及辐射产生的小分子的对比研究发现,各种环氧树脂在电子束辐射下均有不同程度的辐射分解反应发生。其中,以缩水甘油酯型环氧树脂和含酯基的环氧树脂的分解最为严重,缩水甘油胺环氧树脂次之,缩水甘油醚环氧树脂受电子束辐射的降解影响最小。     

电子入射角对束流传输系数和能量沉积的影响

利用数值方法研究了不同能量 (0 .4— 1.4MeV)的电子束以不同的入射角穿透不同厚度碳靶的束流传输系数和能量沉积。计算结果表明 ,随着电子束入射角的增大 ,束流的传输系数减小 ,而较小入射角 (接近垂直入射角 )的电子在靶材料中穿透深度更大 ;能量为 1.0— 1.4MeV的电子束当入射角在 6 0°— 70°时在碳靶单位体积中沉积的能量最大     

环氧树脂分子量对电子束辐射固化效果的影响

研究了分子量对于环氧树脂电子束辐射固化行为的影响规律。环氧树脂体系的辐射反应速率随分子量增加而下降,在低辐射剂量下,高分子量树脂的固化度和固化层厚度较小,提高辐射剂量,分子量的影响减弱。对于辐射固化程度较高的样品,其玻璃化温度(Tg)和贮能模量(E’)主要受固化度控制。电子束辐射固化的环氧树脂进行热处理后,样品的玻璃化温度和高温E’均有所提高,低分子量树脂的热处理效果更为明显。     

Track structure and energy deposition distribution of heavy ions in liquid water

Progress in theoretical research into track structure and energy deposition distribution of heavy ions in introduced,and some research results are given,such as a Monte Carlo model of heavy ion track structure calculation,frequency distribution of energy deposition inside a electron track and radial dose distribution around a heavy ion path.Moreover,research direction in future is also analysed.     

液态水中重离子径述结构及能量沉积分布的研究

介绍了重离子径述结构及能量沉积分布理论研究的进展情况，给出了重离子ＭｏｎｔｅＣａｒｌｏ计算模型以及电子径迹中的能量沉积几率分布和重离子径向剂量分布等计算结果。     

Relationship between radiation damage anisotropy in MgO and YSZ single crystals and the Ion/Atom ratio deposition parameter in biaxially-textured MgO and YSZ thin films fabricated by ion beam assisted deposition

To elucidate the underlying physics of ion beam assisted deposition (IBAD), irradiation damage effects in magnesia (MgO) and yttria-stabilized zirconia (YSZ) were investigated. Ion irradiations were performed on MgO and YSZ single crystals of three low-index crystallographic orientations using 100 and 150 keV Ar⁺ ions over a fluence range from 1 × 10¹⁴ to 5 × 10¹⁶ Ar/cm². Damage accumulation was analyzed using Rutherford backscattering spectrometry combined with ion channeling. Damage evolution with increasing ion fluence proceeded via several characteristic stages and the total damage exhibited a strong dependence on crystallographic orientation. For both MgO and YSZ, damage anisotropy was maximal at a stage when the damage saturated, with the (1 1 0) crystallographic orientation being the most radiation damage resistant. The Ion/Atom ratio deposition parameter reported for IBAD of MgO and YSZ films was found to correlate with the damage plateau stage described above. Finally, the role of the Ion/Atom ratio is discussed in terms of radiation damage anisotropy mechanism.     

Monte Carlo模拟对放疗中电子反散射谱的研究

电子束治疗腮、耳垂等敏感处肿瘤时,经常需要挡铅以保护正常组织,由此产生电子的反散射效应.本文用蒙特卡罗程序模拟了10MeV临床电子束谱随深度的变化;给出了多种散射体的反散射谱平均能量与基本电子谱平均能量的比值随平均束能量的变化曲线.并从能谱的观点,对反散射效应强弱随深度的变化关系作了定性分析,得到与文献一致的结论.     

Formation and annealing behavior of defect clusters in electron or He-ion irradiated Ti-rich Ti–Al alloys

In order to clarify the effect of He atoms on the formation and annealing behavior of defect clusters in Ti–Al alloys, a Ti–47 at.% Al intermetallic compound has been irradiated with electrons and He-ions. Helium-ion irradiation enhances the nucleation of defect clusters, especially of interstitial loops, at temperatures from 623 to 773 K in both γ-TiAl and ₂-Ti₃Al grains of the sample. However, there is little difference between the annealing temperature ranges of defect clusters in TiAl grains formed by He-ion or electron irradiation at 623 K. The dot-shaped clusters and interstitial loops grow scarcely during annealing, but are annihilated by annealing up to 923 K. Cavities are formed after irradiation with He-ions below 10 dpa at 773 K, but no cavities are formed by electron irradiation up to 30 dpa. The cavities in γ-TiAl and ₂-Ti₃Al grains survive after annealing even at 1053 K for 1.8 ks, keeping their density and diameter to be nearly the same as those in the as-irradiated grains.     

GaP高能重离子辐照损伤及退火的正电子湮没研究

用正电子湮没寿命技术研究２．４＊１０＾１５／ｃｍ＾２和２．２＊１０＾１６／ｃｍ＾２ ８５ＭｅＶ＾１９Ｆ离子辐照ＧａＰ的辐照损伤及其退火效应。结果表明,高低两种注量辐照在ＧａＰ中产生浓度较高的单空位。在３００－１０２３Ｋ温度范围内测量了正电子湮没寿命温度的变化。低注量辐照品在退火过程中有双空位的形成;而高注量辐照样品中观察到比双空位更复杂的缺陷形式,其完全被退火的温度比低剂量辐照的高２５０Ｋ。