电子束光刻中邻近效应的Monte Carlo模拟

电子束光刻不受衍射效应的限制，具有高分辨率和能产生特征尺寸在100nm以下图形的优点。目前，国际上正在将角度限制散射的投影电子束光刻技术作为21世纪100纳米以下器件大规模生产的主流光刻技术进行重点开发。     

出射二次电子表面分布的多重分形谱

本文用ＭｏｎｔｅＣａｒｌｏ方法模拟了１－１０ｋｅＶ的入射电子与固体Ｓｉ的相互作用，在模拟中还对体内的二次电子进行跟踪。对出射二次电子在样品表面的分布进行了多重分形研究。随入射电子能量增大，多重分形谱高度下降，多重分形谱主要向低奇异指数方向扩展。     

Pressure and temperature dependent up-conversion properties of Yb~(3+)-Er~(3+) co-doped BaBi_4Ti_4O_(15) ferroelectric ceramics

Yb3+ and Er3+ co-doped BaBi4Ti4O15(BBT) ceramic samples showed brighter up-conversion photoluminescence(UC-PL) under excitation of 980 nm. The monotonous increase of fluorescence intensity ratio(FIR) from 525 to 550 nm with temperature showed that this material could be used for temperature sensing with the maximum sensitivity to be 0.0046 K–1 and the energy difference was 700 cm–1. Moreover, the sudden change of red and green emissions around 400 oC might imply a phase transition. With increasing pressure up to 4 GPa, the PL intensity decreased but was still strong enough. These results illustrated the wide applications of BBT in high temperature and high pressure conditions.     

电子束光刻中邻近效应校正的几种方法

本文简要介绍了限制电子束光刻分辨率的主要因素之一-邻近效应的产生机制,列举了校正邻近效应的GHOST法、图形区密集度分布法和掩模图形形状改变法,介绍了每种方法的原理、步骤和效果,比较了它们各自的优缺点.     

多孔状的Eu:Y2O3/SiO2的合成与光学性能

采用凝胶溶胶法合成了亚微米尺寸的多孔Eu:Y2O3/SiO2(摩尔比Eu:Y2O3:SiO2=5:100:100)样品,并用扫描电镜、傅立叶变换红外光谱仪、拉曼光谱仪和荧光光谱仪对其形貌、结构和光学性能进行了研究.结果表明,退火后的合成产物是一种含有大量孔隙的块体.这是因为在退火之后,样品中绝大部分的-OH、-C=O基团和一些晶格缺陷等被消除.荧光光谱测量结果显示,样品在退火前Eu3 离子基本上不发光,但在经过720℃下退火6 h以后.Eu3 离子发出的荧光非常强.     

电子轨迹的分形描述

电子轨迹的分形描述李华，丁泽军，吴自勤（中国科学技术大学基础物理中心，合肥２３００２６）电子在固体中的运动轨迹具有分形的特性。本文用ＭｏｎｔｅＣａｒｌｏ方法模拟了１－１０ｋｅＶ能量的不同数目的电子入射到固体Ｓｉ、Ｃｕ、Ａｇ、Ａｕ中的运动轨迹。由盒计数...     

ACS-Ⅱ型破乳剂自动控制系统在炼油厂的应用

通过ACS-Ⅱ型破乳剂自动控制系统在炼油厂原油电脱盐装置上的应用，使药剂以原剂形式注入，工艺得到简化，工人劳动强度降低，操作方便、直观、精度高。同时使设备小型化，减少了设备占地面积，节约了电能及药剂量。     

Raman and luminescence studies on phase transition of EuNbO4 under high pressure

Raman and luminescence studies on the phase transition of europium orthoniobates(EuNbO4) under high pressure were performed. The pressure dependent Raman spectra revealed that an irreversible phase transition from monoclinic phase to M'-fergusonite phase of EuNbO4 occurred at 7.3 GPa, and the two phases coexisted over a pressure range from 7.3 to 13.7 GPa. An obvious discontinuity on luminescence intensity ratio between 5D0 →7F2 and 5D0→7F1 transitions was observed with increasing pressure, indicating also that a phase transition occurred at 7.3 GPa, which was in agreement with the high pressure Raman spectra data. Meanwhile, the Raman and luminescence spectra in the temperature range of 20–300 K showed the structure stability at low temperatures.     

Upconversion luminescence ofNaYF4：Yb,Er nanocrystals with high uniformity

The NaYF4：Yb,Er nanocrystals were synthesized via the thermal decomposition ot metal oleate precursors, lhe nanocrys- tals in hexagonal structure were highly uniform and in size of 25 nm. The bright upconversion luminescence was observed under the excitation of 980 nm laser and the upeonversion emission spectra were investigated at different pump powers. The emission intensity ratio of red light to green light linearly increased with pump power increasing. This result indicated that there existed a large threshold power of saturation pump for the first excitation state in NaYFa：Yb,Er nanocrystals comparing to that in bulk material.     

Nd:YAG连续激光辐照铝合金旋转抛物面的温度效应

为了研究激光推进中激光作用反射面后的温度效应,采用自行设计的温度测量系统对不同激光功率辐照下的旋转抛物面铝合金靶的表面温度进行了测试,得到了不同条件下温度-时间关系曲线。结果表明,激光吸收率随激光入射角的增大而增大;罩面上的表面温度与位置相关,自辐照点至径向各点上的温度符合高斯分布,激光辐照点与其它各点呈现明显不同的升温和降温特点;激光辐照停止约数秒后,旋转抛物面表面上各点的温度趋于一致,之后按同一种热扩散方式和降温曲线变温。