搜索结果: 91-105 共查到“知识库 半导体物理学”相关记录145条 . 查询时间(1.015 秒)
共价半导体的化学键模型
2007/12/12
本文讨论了如何用化学键概念来描述半导体性质,特别是迁移现象。为了方便我们具体针对Ⅲ-V族化合物,通过电子在键间的过渡机率来表述电流,并讨论了电子跃迁的两种机构。最后我们讨论了杂质散射,当把杂质原子对较远和近邻电子的作用区分开后,得到了两种散射机构,相应迁移率部分分别正比于T3/2及T-1/2。
含顺磁杂质超导体中的束缚态
2007/12/12
本文利用广义正则变换和自洽场方法,讨论了单个杂质对超导体的影响。证明在磁性杂质附近,可能形成一个束缚态的元激发,其能量位于能隙之中。求出了能级和波函数的解析表达式,并计算了束缚能级所引起的附加电磁吸收。讨论了与此有关的隧道和高频吸收实验。此外,还讨论了非磁性杂质对连续谱元激发的影响及杂质附近能隙的变化。
锑化铟中载流子的复合过程
2007/12/12
用定态光电导及光磁电的方法测量了p型n型InSb在85—290°K之间的电子及空穴的寿命。在室温附近,所有样品的截流子寿命都趋于同一值,在290°K时为3×10-8秒。从寿命的绝对值及温度依赖关系,以及掺杂对寿命的影响,可以肯定在室温附近起主要作用的复合过程是带间碰撞复合过程。在200°K以下,p型样品中的电子寿命与空穴寿命有很大差别,表明有陷阱作用。用位于价带之上0.05eV的复合中心及位于导带...
跳跃机构与低渗杂半导体杂质电导
2007/12/12
在渗杂度很低时,由于少数杂质电离后引起场的起伏,电子在杂质上主要处于局域状态,电声子作用使电子能够在不同杂质上跳跃,但由于电子坐标算符与电声子作用交换,在电场中电子的运动实际上是一种击穿效应,而由声子束补偿能量。针对低补偿情况,略去复杂能带结构,我们由刘维方程出发,把密度矩阵对电场,然后对电声子作用展开,得到电流表达式及密度矩阵对角元所满足的玻茲曼型方程.只取到重迭积分二次项,我们得到了Mille...
用无限深势阱和有限深势阱2种模型，计算了激子束缚能与球形量子点半径的关系.计算结果表明：对于无限深势阱模型，量子点中激子束缚能随着量子点的半径增加而减小；对于有限深势阱模型，当量子点半径较小时，束缚能随着量子点的半径增加而增加；当量子点半径增加到一定值时，它的束缚能达到最大值，继续增加量子点半径，束缚能反而减少.这些计算结果对深入理解半导体量子点中激子的物理本质具有一定学术意义.
Optical Properties and Determination of Thermal Transformation Parameters for Se0.65Te0.35 High Reflectance Thin Films
Optical Properties and Parameters High Reflectance Chalcogenide Semiconductors Thermal Transformation Parameters
2010/4/9
Chalcogenide glasses Se-Te have been prepared from the high purity constituent elements. Thin films of these materials have been deposited by vacuum evaporation. The thickness effects on the optical p...
Magnetic Levitation of a Small Magnetic Ring Above Cylindrical Superconductor Sample in the Meissner State
Levitation force Meissner state superconducting cylinder
2010/4/9
The levitation force between a cylindrical superconductor in the Meissner state and a small magnetic ring was calculated using the dipole-dipole interaction model under the assumption that the magneti...
Optical and Electrical Properties of Te Doped AlGaAsSb/AlAsSb Bragg Mirrors on InP
Semiconductor Bragg mirror AlGaAs/AlAsSb
2010/10/13
We present a comparative study carried out on the optical and electrical characteristics of undoped and Te doped AlGaAsSb/AlAsSb Bragg mirrors with 6.5 pairs of layers and bulk undoped and Te doped Al...
Effects of Disorder on the Exchange Coupling in (Ga,Mn)As Diluted Magnetic Semiconductors
Disorder Exchange coupling Diluted magnetic semiconductors
2010/8/26
A theoretical study of the effects of disorder on the Mn-Mn exchange interactions for Ga1¡xMnxAs diluted magnetic semiconductors is presented. The disorder is intrinsically considered in the cal...
Transport Properties of a Ga1-xMnxAs/Ga1-yAlyAs Double-Barrier
Double barrier spin polarizer Diluted magnetic semiconductors Spintronic devices
2010/8/26
We study the transport properties of a spin filter consisting of a double-barrier resonant tunneling device in which the well is made of a semimagnetic material. Even if the device could be made of se...
Analysis of the Chemical Bath and its Effect on the Physical Properties of CdS/ITO thin Films
Chemical bath analysis Cadmium sulphide Semiconductor film Predominance diagrams
2010/9/29
Cadmium sulphide (CdS) thin films deposited on indium tin oxide (ITO) substrates were prepared by the chemical bath deposition technique at different values of pH and pNH3. This was made in order to a...
Two-photon Absorption Processes in Semiconductor Quantum Dots
Nonlinear absorption Two-photon absorption Quantum dots
2010/9/29
The two-photon absorption process is a nonlinear phenomenon that shows very low optical efficiency in bulk
semiconductors. For this reason the detection of these processes becomes very difficult from...
Thin-film ZnO/CdS/CuIn1 - xGaxSe2 Solar Cells: Anomalous Physical Properties of the CuIn1 - xGaxSe2 Absorber
Solar cells Photovoltaic Absorbers CuInSe2 Surface Interface Defects
2010/9/29
Thin-film ZnO/CdS/CuIn1¡xGaxSe2 solar cells are manufactured with »20% solar-cell conversion efficiency. The CuIn1¡xGaxSe2 (CIGS) absorber exhibits rather different physical properti...