Ge(Li)γ谱本底的直接扣除法

本文介绍了一种直接扣除峰下本底的技术,这个技术已在《SPAN Ge(Li)γ谱分析程序》中得到成功的应用。这个方法是积分峰本底技术的完善和发展,它对于十分复杂的包含有多重峰的Ge(Li)γ谱也能得出合理的本底线,并且能从γ谱中直接扣除。     

Catalytic hydrogenation for improvement of GaAs/Ge solar cell efficiency

Hydrogen passivation on MOCVD grown p-GaAs epilayers on Ge substrate have been studied by plasma and catalytic hydrogenation and the results were compared. The conversion efficiency of the GaAs/Ge solar cells was found to increase by 10% after catalytic hydrogenation at AM1.5. This increase in efficiency is probably due to passivation of surface dangling bonds.     

超薄体MOSFET的结构优化

对UTB器件的各结构参数进行了优化,给出了UTB器件设计的指导方向.在UTB器件的设计中,有三个重要参数,即器件的源漏提升高度、锗硅栅(GexSi1-x)中Ge含量的摩尔百分比和硅膜的厚度,并对这三个结构参数对器件性能的影响进行了模拟分析,给出了器件各结构参数的优化方向,找出了可行Ge含量的摩尔百分比和可行硅膜厚度之间的设计容区.通过模拟分析发现,只要合理选择器件的结构参数,就能得到性能优良的UTB器件.     

Ce–Ti–Ge system at 1170 K

Phase equilibria in the Ce–Ti–Ge system were investigated by X-ray powder diffraction, electron probe X-ray analysis and the isothermal section at 1170 K was obtained. We confirmed the CeFeSi-type CeTiGe compound (a=0.4135 (1) nm, c=0.7921 (1) nm, space group P4/nmm, No. 129). A new compound, Ce₂₀Ti₂₀Ge₆₀, was found (a=0.3967(6) nm, c=6.054 (2) nm, space group P4). It is obvious that the ThSi₂-type Ce₃₃Ti₇Ge₅₄ compound (a=0.4217 (1) nm, c=1.4184 (3) nm, space group I4₁/amd, No. 141) belongs to the extended solid solution region of the ThSi₂-type CeGe₂ compound.     

微型反应堆辐照座内中子温度和超热指标的测定

一、引言对于高浓铀燃料、金属铍反射层,主要作为中子活化分析用的微型反应堆而言,对有关辐照座内的能谱和谱参数必须有所了解,中子温度是重要的谱参数,它基本上反映了反应堆热谱的特征。     

同步仿生机械臂设计

本设计利用安装在人手臂部的加速度传感器采集运动信号,单片机智能运算后发出控制指令,实现机械臂与人臂的同步运动。系统将在采集传感器的输出模拟量经过单片机的处理产生PWM波,使用PWM波驱动舵机实现准确定位,使机械臂实现三自由度的运动。而且还可通过编程和仿生来完成各种预期的作业任务,在构造和性能上兼有人和机器各自的优点,体现了人的智能和适应性。     

半导体纳米晶体在薄膜晶体管中的应用

以非晶硅薄膜为核心的薄膜晶体管技术目前已经相当成熟,在该技术投入使用并且得以很好地优化之后,要想进一步提高薄膜晶体管的性能,就有必要开发新型的薄膜材料。近年来,由半导体纳米晶体构成的新型薄膜材料在晶体管中的应用越来越受到人们关注。利用半导体纳米晶体制备的薄膜晶体管有着较高的载流子迁移率和开关电流比,同时在其制备过程中可以在较低温度下大面积成膜,能够使用塑料等柔性衬底,因而具有明显的成本优势,发展前景广阔。着重介绍了几种颇具潜力的半导体(如硒化镉、碲化汞、硒化铅、锗、硅)纳米晶体在制备薄膜晶体管方面的应用。     

退火温度对CuGa_(0.8)Ge_(0.2)Se_2薄膜结构及光学特性的影响

采用脉冲激光沉积法在SiO2衬底上制备了CuGa0.8Ge0.2Se2薄膜。采用X射线衍射和X射线能谱仪研究了退火温度对薄膜晶体结构和成分的影响,利用扫描电子显微镜表征了薄膜的表面形貌,采用紫外—可见分光光度计分析了薄膜的光学特性。结果表明,在CuGaSe2中掺杂Ⅳ族元素Ge,光子吸收能量分别为0.65和0.92 e V,禁带宽度为1.57 e V,能够形成中间带。并随着退火温度的升高,CuGa0.8Ge0.2Se2薄膜的光学带隙逐渐减小。     

GaAs/Ge solar cell AC parameters under illumination

The ac parameters of GaAs/Ge solar cell were measured under illumination at different cell temperatures using impedance spectroscopy technique. They are compared with the dark measurements. It is found that the cell capacitance is higher and cell resistance is lower under illumination than in dark for all cell terminal voltages. The cell capacitances at the corresponding maximum power point voltage (terminal) do not vary with temperature where as the cell resistance decreases. The cell capacitance under illumination is estimated from the dark cell capacitance and it is in good agreement with the measured illumination data.