Electrical Properties of La-Doped Al2O3 Films on Si （100） Substrates as a High-Dielectric-Constant Gate Material

Amorphous La-doped Al2O3 （La： Al2O3） thin films are deposited on n-type （100） Si substrates by rf magnetron co-sputterlng. The composition of the deposited films is measured by energy dispersive x-ray spectroscopy： Capacitance-voltage measurement shows that the dielectric constant k of La-doped Al2O3 films ranges from 8.5 to 11.6 with the increasing La content, and the highest k value of 11.6 is obtained for the 20.14% La content film. In the structure of the Al/La：Al2O3/Si metal oxide semiconductor, the dominant conduction stems from the space- charge-limited current at different temperatures. In addition, the wavelength dependence of the transmittance is studied by ultraviolet spectroscopy and the band gap of all the deposited films is above 5.5eV. The results demonstrate that La-doped Al2O3 can meet the requirement of next-generation gate materials.     

光电效应实验仪器及实验方法的改进

对ZKY－GD－3型光电效应实验仪做了测试研究，给出了普朗克常量的实验结果。     

Relaxor Behaviour and Ferroelectric Properties of （Li0.12Na0.88） （Nb0.9-xWa0.10Sbx）O3 Lead-Free Ceramics

New lead-free ceramics （Lio.12Na0.88） （Nbo.9-x Ta0.10 Sbx） 03 （0.01 × 0.06） are synthesized by solid-state reaction method. The dielectric, piezoelectric and ferroelectric properties of the ceramics are studied. The dielectric constant dependence with temperature and frequency of the ceramic specimen with x = 0.04 shows typical characteristics of relaxor ferroelectrics, and the Vogel-Fulcher relationship is fulfilled. The dielectric behaviour and its relation to the phase transition phenomena are discussed. The polarization hysteresis loops at room temperature are also measured.     

简谈普适气体常量R——贯穿普化教育的重要常量

The universal gas constant R is an important constant in physics, and one of the vital fundamental constant throughout the teaching of general chemistry. This article aims to present a general review about the universal gas constant to the science and engineering majored students, including its history, determination, physical meaning and applications in chemical education. The choice of R values under various conditions is also provided to help students better understand and master basic concepts.     

氧化铟锡薄膜的椭偏光谱研究

用溅射法在Si片上制备了厚度为140nm的氧化铟锡(ITO)薄膜。X射线衍射研究表明所制备的薄膜为多晶结构。在1.5~4.5eV范围内对ITO薄膜进行了椭偏测量。分别用德鲁德-洛伦茨谐振子(Drude Lorenz oscillators)模型、层进模型结合有效介质近似模型对椭偏参量ψ、Δ进行了拟合,得到ITO薄膜的折射指数n的变化范围在1.8~2.6之间,可见光范围内消光系数k接近于零,在350nm波长附近开始明显变化,且随着波长的减小k迅速增加。计算得到直接和间接光学带隙分别是3.8eV和4.2eV。并在1.5~4.5eV段给出一套较为可靠的、具有实用价值的ITO介电常量和光学常量。     

氢原子光谱实验求里德伯常量的数据处理方法

分析了氢原子拳谱实验中求里德伯常量的多种数据处理方法,得出了以波长为因变量的过原点直线拟合的方法和用各波长求RH后加权平均的方法较为合理的结论.     

应用迈克耳孙干涉仪研究压电陶瓷的特性

简述了应用迈克耳孙干涉仪测量压电陶瓷压电常量的原理及实验结果分析.简单介绍了研究压电陶瓷振动特性的方法.     

真空介电常量和真空磁导率在高斯单位制中的数值

首先由ε 0和μ0在国际单位制中的数值得出其在高斯单位中的数值, 然后利用之, 把电磁学公式由S I制 化到G a u s s制, 并利用它解释了存在真空极化的合理性, 及“ 真空磁化”的存在     

R2Fe17-xAlx化合物中R-T交换耦合常量的计算

讨论了利用分子场近似结合中子衍射或X射线衍射的实验结果计算R2Fe17型稀土过渡族化合物中稀土磁矩与过渡族磁矩之间交换耦合常量的方法,并据此计算了R2Fe17-xAlx(R=Tb,Dy,Ho,Er,Gd,x=7或8)化合物中稀土磁矩与过渡族磁矩之间的交换耦合常量.计算结果与实验值符合较好.     

三胶子张量算符反常量纲的计算

计算了两个与量子数为J^PC=1^－+的胶球流算符密切相关的三胶子张量算符Ωαβ1=Gαa,μ Gμb,ν Gνβc f_abc和Ωαβ2=gαβ Gσa,μ Gμb,ν Gνc,σ f_abc的重整化矩阵和反常量纲矩阵.