RBS/channeling studies on the heteroepitaxially grown Y2O3 film on Si(100)

The heteroepitaxially grown yttrium oxide layer by an ionized cluster beam (ICB) on a Si(100) substrate was investigated by Rutherford backscattering spectrometry (RBS)/channeling. The channeling minimum value (χ_min) of the Y₂O₃ layer on Si(100) is 0.28, and this is the smallest value among those reported. From the channeling polar plots, it is found that Y₂O₃ film grown on Si(100) oriented with (110) direction and has a double domain structure. The 110 axis of Y₂O₃ layer is exactly parallel to the 100 axis of the Si substrate. It is also observed that the interface region of Y₂O₃ film has more crystalline defects than the surface region.     

As离子束混合形成硅化钨的卢瑟福背散射分析

本工作用卢瑟福背散射研究了离子束混合方法形成硅化钨的条件。通过对热烧结和离子束混合法的比较,结合X射线衍射分析相结构的结果,指出离子束混合法可降低形成二硅化钨所需的退火温度。观察到氧杂质对形成条件的影响,简单讨论了离子束混合形成硅化物的机理。     

轨道飞行目标的雷达回波模拟及成像

逆综合孔径雷达（ＩＳＡＲ）是国内９０年代初新兴的一个课题，近几年对空中目标成像的取得了很大的进展，本文通过计算目标后向散射场来模拟轨道飞行目标的ＩＳＡＲ回波，讨论模拟和成像过程并给出模拟成像结果，同时分析了轨道飞行目标成像对雷达重复频率和相干积累时间的要求。     

Resonant Rutherford backscattering. Study ofa-axis YBaCuO films with very high crystallinity

Hybrid sputtering and the conventional dc-template sputtering methods were used to deposit highly crystallinea-axis films. The oxygen contents and disorder of the films were measured by the resonant Rutherford backscattering. The oxygen content of the films deposited by the hybrid sputtering depend on the deposition temperature. Films deposited at a low temperature have low oxygen content. The poor superconducting properties of these films may be due to the oxygen deficiency. The stoichiometry of the films deposited by the dc-template sputtering method was found to depend on the microstructure of the template. The disorder at the Ba and O sublattices of these highly crystallinea-axis films are uncorrelated.     

Rutherford-backscattering study of high-temperature oxidation of Y-implanted Fe-24Cr

We have investigated the effect of Y ion implantation on the high-Temperature oxidation of Fe-24Cr using Rutherford-backscattering spectroscopy, secondary ion mass spectroscopy, and analytical electron microscopy. Results indicate that implantation of Y has a very large effect on the growth rate of the oxide compared to metals alloyed with Y. Analytical tools have been applied to determine the spatial distribution of Y, the microstructure of the oxide, and contribution of oxygen transport to the oxidation process. Results are compared with those of recent cation-diffusion measurements in Cr₂O₃ and Cr₂O₃ doped with Y₂O₃.     

Complexation of uranyl ions by polypyrrole doped by sulfonated and phosphonated polyethyleneimine

Branched polyethyleneimine (PEI) was sulfonated by reaction with chloropropanesulfonylchloride and phosphonated by reaction with phosphorous acid and formaldehyde. The accordingly formed polyanions were used as doping agents for polypyrrole (PPy). The amount of doping polyanions into thin films of PPy was measured by Rutherford back‐scattering. These films were tested for their capacity to extract uranyl ions from liquid wastes of low level activity. The uranium content was determined by neutron activation analysis, autoradiography, and gravimetry of uranium oxide after calcination. The resistance against static and dynamic leachings was also estimated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 352–359, 2003     

Partial crystallization of as-quenched Zr55Cu30Al10Ni5 bulk metallic glass induced by oxygen

Dendritic crystals, randomly distributed into the as-quenched Zr₅₅Cu₃₀Al₁₀Ni₅ bulk metallic glass were characterized by optical microscopy, electron probe microanalysis, X-ray diffraction and electron backscattering diffraction. Oxygen enrichment is observed into these crystallites (formula: Zr₇Cu₄Al₃O, space group: Fd m, cell parameter: 5.70 Å) demonstrating the negative effect of oxygen, inducing partial crystallization during casting.     

半导体激光后向定位仪

一种可见光半导体激光后向接收定位，测位仪，达到了先进的技术性能，在钢铁、冶金等行业具有较好的应用前景。     

Ion beam mixing characteristics of MOCVD grown InGaAs/GaAs superlattices

The ion beam mixing behavior of InGaAs/GaAs strained layer superlattice structures grown by metalorganic chemical vapor deposition was studied using secondary ion mass spectroscopy and Rutherford backscattering channeling. The fluence dependence of intermixing by MeV Kr⁺ irradiation has been investigated. Significant intermixing occurs for fluences much lower than for similar intermixing in other superlattice systems (i.e. ALAs/GaAs). The intermixing exhibits no temperature dependence for fluences of 2 x 10¹⁵ to 5 x 10¹⁵ cm⁻² which sharply contrasts with the behavior of the AlAs/GaAs superlattice system which shows a strong temperature dependence, including a miscibility gap, in the temperature range 523 to 973K. Samples irradiated at 573K retain a high degree of crystallinity when compared to lower temperature irradiations indicating that the InGaAs/GaAs superlattice can be disordered and still retain crystallinity.     

Panchromatic cathodoluminescence characterization of III-V lattice-mismatched heterostructures

Some examples of the possibilities that panchromatic cathodoluminescence (PCL) offers in the scanning electron microscopy (SEM) characterization of III-V semiconductors are presented. Investigations on lattice-mismatched InGaAs/InP, InGaAs/ GaAs single heterostructures, and InGaAs/GaAs superlattices and GaAs/Ge and GaAs/InP single layers are shown. Further, the use of PCL as a support in the nondestructive determination of the sensitivity limit of Rutherford backscattering and x-ray diffraction techniques in the study of strain release in some of the above mentioned heterostructures is presented. Finally, PCL on-line study of dislocation movement induced by electron beam irradiation in the SEM, as evidence of InGaAs/GaAs superlattice metastability, is also presented.