掺铁半绝缘磷化铟的深能级研究

文章简要地叙述了光激电流瞬态谱(PICTS)及恒流光电导(CCPC)设备的建立过程及测量方法。并首次用二种方法结合起来以研究掺铁半绝缘磷化铟(InP)中深能级的热电离能,载流子的发射与俘获特性,杂质波函数的局域程度及电子与晶格之间的相互作用。并给出了铁能级在禁带中的确切能量位置。     

Trap spectroscopy of a-Si:H diodes using transient current techniques

Transient current techniques have been applied to hydrogenated amorphous silicon (a-Si:H) solar cells to obtain information about the electron traps in the upper half of the band gap. These studies lead to the conclusion that electron trapping occurs in specific regions distributed throughout the a-Si:H. A model based on these trapping regions becoming negatively charged as electrons are captured and thus opposing further capture is presented. Because of this inhomogeneous capture only the lower limit to the density of traps is obtained.     

氢对硅中4d过渡杂质的钝化

本文研究了氢原子与Ｓｉ中４ｄ过渡杂（Ｐｄ，Ｒｈ，Ｒｕ，Ｍｏ）引入深入中心的相互作用，得到了Ｓｉ中这些深中心被钝化的难易程度。从钝化角度支持了Ｓｉ：Ｐｄ与Ｓｉ：Ｒｈ中有关能级属于同一中心、不同荷电态的判断，同时提出了Ｓｉ：Ｍｏ中Ｅ（０．５３）和Ｈ（０．１６）两个能级属于同一中心、不同荷电态的证据，通过氢对已知同一中心、不同荷电态两个能级的相互作用，对氢的钝化机理作了初步探讨。     

深亚微米薄膜SOI MOSFET的二维数值模拟

本文介绍了适合于薄膜亚微米、深亚微米ＳＯＩＭＯＳＦＥＴ的二维数值模拟软件。该模拟软件同时考虑了两种载流子的产生－复合作用，采用了独特的动态二步法求解泊松方程和电子、空穴的电流连续性方程，提高了计算效率和收敛性。利用此模拟软件较为详细地分析了薄膜ＳＯＩＭＯＳＦＥＴ不同于厚膜ＳＯＩＭＯＳＦＥＴ的工作机理及特性，发现薄膜ＳＯＩＭＯＳＦＥＴ的所有特性几乎都得到了改善。将模拟结果与实验结果进行了对比，两者吻合得较好。     

DEEP LEVELS RELATED TO COPPER IN SILICON

Energy positions and carrier capture cross sections of the deep levels related to copper insilicon are measured by the DLTS.The annealing behaviour and spatial distributions of some of these levelsare also studied.The results show that there are no triple aceeptor or quadruple states corresponding to thesubstitutional copper in silicon,which have been reported in literature.Most of the deep levels related tocopper in silicon correspond to complexes of copper and defects in silicon.     

1:1分步亚微米光刻镜头

本文介绍一个数值孔径0.4、视场10×10mm~2可用于1:1分步投影光刻机的镜头的光学设计及其模型实验结果.光学设计在Wynne-Dyson的1:1折反式系统的基础上,对该系统作了某些改变.实验结果表明,该镜头具有亚微米的光刻分辨率.     

Trapping and recombination processes via deep level T3 in semi-insulating gallium arsenide

Trapping and recombination of free carriers by deep level T₃ has been studied. Occupancy of the level by electrons and dynamics of its filling and emptying as a function of illumination with monoenergetic photons in 0.69–1.55 eV range has been monitored by the thermally stimulated currents method. We have found that level T₃ behaves more like a recombination center than like an ordinary electron trap. Besides trapping free electrons from conduction band, this trap can also communicate with valence band, trapping holes. The capture cross section for trapping a hole is estimated to be comparable or even larger than the capture cross section for trapping an electron. However, in many experimental conditions free electrons are generated more abundantly than free holes, and free carrier mobility and thermal velocity are both much higher for electrons than for holes. Therefore, electron trapping often prevails, so that this frequently detected defect, has been up to now most often perceived as a deep electron trap.     

Study of n type porous GaAs by photoluminescence spectroscopy: Effect of the etching time on the deep levels

Photoluminescence (PL) analysis is used to study porous layers elaborated by electrochemical etching of n⁺ Si-doped GaAs substrate with different etching times. Temperature and power dependence photoluminescence (PL) studies were achieved to characterize the effect of the etching time on the deep levels of the n⁺ Si-doped GaAs. The energy emission at about 1.46 eV is attributed to the band-to-band (B-B) (e-h) recombination of a hole gas with electrons in the conduction band. The emission band is composed of four deep levels due to the complex of (V_AsSi_GaV_Ga), a complex of a (Ga vacancy - donor - As vacancy), a (Si_Ga-V_Ga³⁻) defect or Si clustering, and a (gallium antisite double acceptor-effective mass donor pair complex) and which peaked, respectively, at about (0.94, 1, 1.14, and 1.32 eV). The PL intensity behavior as function of the temperature is investigated, and the experimental results are fitted with a rate equation model with double thermal activation energies.     

基于监督对比学习正则化的高分辨率SAR图像建筑物提取方法

近年来,高分辨合成孔径雷达(SAR)图像的智能解译技术在城市规划、变化监测等方面得到了广泛应用.不同于光学图像,SAR图像的获取方式、图像中目标的几何结构等因素制约了现有深度学习方法对SAR图像地物目标的解译效果.该文针对高分辨SAR图像城市区域建筑物提取,提出了基于监督对比学习的正则化方法,其主要思想是增强同一类别像...     

Measurement of momentum distribution of lightatoms and molecules in condensed matter systems using inelastic neutron scattering

Studies of single-particle momentum distributions in light atoms and molecules are reviewed with specific emphasis on experimental measurements using the deep inelastic neutron scattering technique at eV energies. The technique has undergone a remarkable development since the mid-1980s, when intense fluxes of epithermal neutrons were made available from pulsed neutron sources. These types of measurements provide a probe of the short-time dynamics of the recoiling atoms or molecules as well as information on the local structure of the materials. The paper introduces both the theoretical framework for the interpretation of deep inelastic neutron scattering experiments and thoroughly illustrates the physical principles underlying the impulse approximation from light atoms and molecules. The most relevant experimental studies performed on a variety of condensed matter systems in the last 20 years are reviewed. The experimental technique is critically presented in the context of a full list of published work. It is shown how, in some cases, these measurements can be used to extract directly the effective Born–Oppenheimer potential. A summary of the progress made to date in instrument development is also provided. Current data analysis and the interpretation of the results for a variety of physical systems is chosen to illustrate the scope and power of the method. The review ends with a brief consideration of likely developments in the foreseeable future. Particular discussion is given to the use of the VESUVIO spectrometer at ISIS.

Measurement of momentum distribution of lightatoms and molecules in condensed matter systems using inelastic neutron scattering

All authors

C. Andreani, D. Colognesi, J. Mayers, G. F. Reiter &; R. Senesi

https://doi.org/10.1080/00018730500403136

Published online:

19 February 2007

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