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131.
本文将Gartener方程应用于硅材料,并提出了称之为I_o/I_(ph)-α~(-1)法的光电化学法,用于测定硅中少子扩散长度.文中研究了实验条件对测量结果的影响,讨论了该法的实用价值和给出了与SPV法对比的实验结果. 相似文献
132.
C. Astaldi
A. Santoni
F. Della Valle
R. Rosei
《Surface science》1989,220(2-3):322-332The kinetics of atomic carbon and oxygen buildup on a Ni(100) surface exposed to carbon monoxide at high temperatures have been investigated by Auger electron spectroscopy. The experimental data, taken at different sample temperatures (453 , T 573 K) and at different CO partial pressures (3 ×10−7</sup> , Pco , 3 ×10−1</sup> mbar) allowed the identification of the CO dissociation mechanism. By fitting the experimental data with a set of rate equations describing CO dissociation, CO reduction of surface oxygen, and C and O recombination, we have been able to determine the pre-exponential factors and the activation energies of these processes. 相似文献
133.
B. C. Bunker D. M. Haaland K. J. Ward T. A. Michalske W. L. Smith
J. S. Binkley
C. F. MeliusC. A. Balfe
《Surface science》1989,210(3):406-428Dehydroxylated silica exhibits two well-defined infrared bands at 888 and 907 cm−1</sup> previously assigned to a highly reactive strained surface defect. Comparisons of the spectra of dehydroxylated silica to frequencies and intensities calculated using molecular orbital (MO) calculations and to spectra obtained for cyclodisiloxanes suggest that the strained surface defect consists of an edge-shared silicate tetrahedral ring. Changes in vibrational frequencies and peak intensities with 18</sup>O labeling for both the surface defect and the cyclodisiloxanes are consistent with those expected for ring vibrational modes. The IR bands associated with the strained edge-shared ring disappear when either the surface defects or the cyclodisiloxanes react with water. Reactions of the surface defect can be used to study how strain enhances the reactivity of Si-O-Si bonds for modeling phenomena such as stress corrosion cracking. 相似文献
134.
135.
We propose an analytical approach to study the electron transport in semiconductors when a strong high frequency (HF) electric field is applied together with a weak direct current (DC) electric field. We derive a set of dynamic equations, from which the amplitude and phase of each harmonic component of the electron drift velocity and the electron temperature can be obtained. Our calculation shows that the DC conductivity in an n-GaAs sample decreases dramatically with increase of the first and second harmonic applied electric fields and definitely becomes negative. 相似文献
136.
This paper presents a MEMS Resonant Pressure Transducers (RPT) that is produced using a flexible fabrication route to allow pressure ranges from 1bar to 700bar in fully oil isolated hermetic packages without compromising sensor performance. The fabrication method makes use of silicon fusion bonding (SFB) and deep reactive ion etching (DRIE) to build up a three-layer die, with the middle layer consisting of a strain sensitive resonator. The key aspects of the fabrication process and sensor design that make this possible are presented, along with data showing long-term stability of better than 100ppm drift per year. 相似文献
138.
宽带IP城域网及其应用 总被引:1,自引:0,他引:1
文章结合南京电信公众宽带IP城域网的建设,对宽带IP城域网的网络结构、用户接入安全、网络管理和认证计费作了阐述,并简要介绍了应用于宽带IP城域网上的一些业务。 相似文献
139.
George Eng Pamela K. McKinney-Forbes Kristy L. Richie Van V. Nguyen
Leopold May
《Journal of organometallic chemistry》1986,310(3):285-291To obtain more structural information on complexes formed between alkyltin halides and bidentate ligands, the solid-state IR and Mössbauer spectra of the 1,2-ethanediamine and 1,4-butanediamine complexes of trimethyltin halides and dimethyltin dihalides were examined. The structures of the trimethyltin halide complexes were found to be trigonal bipyramidal with coplnar methyl groups. The dimethyltin dihalide complexes were octahedral with the methyl groups in the cis-positions and the halides trans to each other. However, there were no differences in the structures of the chloro and bromo complexes of either type. 相似文献
140.
洁净硅表面在电子束的作用下产生诱导氧化现象,在AES分析中已得到证实。本文利用TEM 200CX型电镜研究了洁净硅表面在电子束作用下的结果,实验表明,在TEM中同样存在着电子束诱导硅表面氧化的现象,氧化生成了SiO_2微晶,其氧主要来自硅晶体内氧的局部富集和电镜中残余气体在硅表面的吸附。 相似文献