半导体光电化学法测定半导体材料的物理参数

光电化学技术以它许多独特的优点为半导体性能测试提供了一种灵敏、方便,有时是其它方法也难以达到的综合性测试方法,尤其是对多层及异质结构材料多数的剖面分布测量.因此,它已广泛应用于材料性能测试和器件工艺.本文总结了半导体材料特性参数的光电化学测试技术,包括导电类型、p-n结位置、载流子浓度、少子扩散长度、深能级、禁带宽度、材料组份,以及部分参数的剖面分布的测定.介绍了国内外的研究进展.     

硅扩散型压力敏感元器件的研制

硅扩散型压力传感器件自70年代问世以来,由于它有诸多优点,受到许多技术先进国家的重视.本文着重介绍作者所做的工作,即扩散型压力敏感元器件的特点、压力效应、圆片应力分析、制造的关键工艺和敏感元器件的结构设计及其应用,并提出对今后研究发展的见解.     

MOSFET的热载流子效应及其寿命的评估方法

首先简单地讨论热载流子效应的背景及其物理机制.然后,提出了一种常用的用来推算金属氧化物场效应晶体管的热载流子效应的寿命的模型,Hu模型.在这些研究的基础上,才能更好地研究来削弱MOSFET的热载流子效应及提高MOSFET的热载流子效应的寿命的方法.     

半导体制冷技术研究

本文讨论了目前制冷技术存在的问题,详尽分析了半导体制冷的特点、应用及发展动向。     

二氧化锡／多孔硅／硅的吸附特性

研究了二氧化锡／多孔硅／硅（ＳｎＯ＿２／ＰＳ／Ｓｉ）的光伏谱和吸附性质，由分析光伏谱得出在ＳｎＯ＿２／ＰＳ／Ｓｉ之间存在着二个异质结：一个是ＳｎＯ＿２／ＰＳ异质结；另一个是ＰＳ／Ｓｉ异质结，当样品吸附ＣＯ气体后，光电压明显减少，实验结果表明，利用光电压的变化可以检测ＣＯ等有害气体．本文对新气体敏感材料ＳｎＯ＿２／ＰＳ／Ｓｉ的有关气体吸附机制进行了讨论．     

Differenc es between amorphous indium oxide thin films

A series of 60~nm thick indium oxide thin-films,all amorphous as determined by x-ray diffraction,were found to have physical and electrical properties that depended on the temperature of deposition.The carrier mobility and flm conductivity decreased with decreasing deposition temperature;the best electrical properties of high mobility and conductivity were observed at a deposition temperature just below the temperature at which crystalline films formed.The density of the flm also decreased with deposition temperature from 7.2g/cm3 at+50℃ to 5.3g/cm3 at 100℃.     

电子速度对半导体量子点中极化子的声子平均数的影响

采用改进的线性组合算符和幺正变换方法研究半导体量子点中强、弱耦合极化子的振动频率和声子平均数的性质．导出了电子速度对半导体量子点中强、弱耦合极化子的声子平均数的影响．数值计算结果表明：半导体量子点中强耦合极化子的振动频率随量子点的受限强度的增加而增大，半导体量子点中强、弱耦合极化子的声子平均数随电子速度的增加而增加     

BCN非晶形成机理的实验研究

以六方ＢＮ和石墨粉为原料，通过机械球磨的方法制备出ＢＣＮ非晶粉，对ＢＣＮ非晶的成键状态和形成机理进行了实验研究。     

In-situ potential mapping of space charge layer in GaN nanowires under electrical field by off-axis electron holography

In situ potential mapping of space charge(SC) layer in a single Ga N nanowire(NW) contacted to the Au metal electrode has been conducted using off-axis electron holography in order to study the space distribution of SC layer under electric biases. Based on the phase image reconstructed from the complex hologram the electrostatic potential at the SC layer was clearly revealed; the SC width was estimated to be about 76 nm under zero bias condition. In order to study dynamic interrelation between the SC layer and bias conditions, the variation of the electrostatic potential due to change of the SC widths respond to the different bias conditions have also been examined. The measured SC layers are found to vary between68 nm and 91 nm, which correspond to the saturated SC layers at the Ga N-Au contact under the forward and reverse bias conditions, respectively. By plotting the square widths of the SC layer against the applied voltages, donor density of Ga N NWs was derived to be about 4.3*10~6cm~(-3). Our experiments demonstrate that in-situ electron holography under electric fi eld can be a useful method to investigate SC layers and donor density in single NW and other heterostructures.     

Ethylene glycol-assisted synthesis,photoelectrochemical and photocatalytic properties of BiOI microflowers

Hierarchical bismuth oxyiodide （BiOI） micro- flower photocatalysts were synthesized by hydrolysis at room temperature. The concentration of ethylene glycol modulated the resulting BiOI morphology. The morphology, elemental composition, crystal phase structre, and absorption properties of the BiOI samples were characterized. Under visible light irradiation （λ 〉 400 nm）, BiOI （S10） with a microflower morphology exhibited the highest photocatalytic activity in the degradation of methyl orange. The corresponding apparent pseudo-first-order rate constant was 0.826 h^-1. The trend in photocatalytic activities of the prepared BiOI samples coincided with the trend in their photocurrents. A strategy for preparing hierarchical BiOI microflowers with good visible light- induced photocatalytic activity is provided.