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A preliminary study of the formation of WSi2 by high-current W ion implantation

摘要：
Two differently structured WSi2 phases were formed by direct W ion implantation, for the first time, into silicon wafers using a metal vapour vacuum arc ion source. Implantation of W ions was conducted with an extract voltage of 40 kV, various beam densities from 50 to 115 mu A cm^-2 and a fixed dose of 5*10¹⁷ cm^-2. It was found that the formation of WSi2 with either a hexagonal or a tetragonal structure depended on the ion current density. The temperature rise caused by beam heating and the beam-striking time related to the dose were calculated, and they were responsible for the formation and evolution related to the differently structured WSi2 phases.
作者：
Zhu D. H.;Lu H. B.;Tao K.;Liu B. X.
刊名：
Journal of Physics Condensed Matter
在线出版时间：
1993

Formation of a CoSi2 layer by Co ion implantation using a metal vapor vacuum arc ion source

摘要：
CoSi2 was formed by metal vapor vacuum arc ion implantation in both crystalline silicon and crystalline silicon deposited with a thin Co film. When the Si(111) wafers were implanted by Co ions at an extracted voltage of 40 kV with a current density of 100 and 152 μA/cm² to a fixed nominal dose of 2 × 10¹⁷/cm², a continuous CoSi2 layer was formed and the resistivities were in the range of 14-20 μΩ cm. When the Si wafers deposited with a Co film were implanted by Co ions at an extracted voltage of 20 kV with a current density of 100 μA/cm² to a dose ranging from 2 × 10¹⁷ /cm² to 6 × 10¹⁷ /cm², several Co-silicides were observed. Increasing the implanted dose or post-implantation annealing facilitated Co consumption and the transition from Co-rich silicide to CoSi2. © 1995.
作者：
Zhu D. H.;Chen Y. G.;Liu B. X.
刊名：
Nuclear Inst and Methods in Physics Research B
在线出版时间：
1995

C54-TiSi2 formed by direct high current Ti-ion implantation

摘要：
We report, in this letter, the formation of TiSi2 by direct Ti-ion implantation into silicon wafers using a metal vapor vacuum arc ion source. Implantation was conducted by 80 KeV Ti ions to a dose of 5×10¹⁷/cm² with various ion current densities. When the ion current density exceeded 100 μA/cm², the equilibrium TiSi2 of the C54 structure was uniquely formed. Additional evidence of the formation of C54-TiSi2 was given by the resistivity measurements, i.e., the sheet resistivity was below 3.0 Ω/. The formation mechanism is also discussed in terms of the beam heating effect during implantation.
作者：
Zhu D. H.;Tao K.;Pan F.;Liu B. X.
刊名：
Applied Physics Letters
在线出版时间：
1993

Annealing-induced blue shift in luminescence band from Si-implanted SiO2 layer

摘要：
The SiO2 layers thermally grown on Si wafers were implanted by 130 keV Si ions at liquid nitrogen temperature to a dose of 1×10¹⁷ ions/cm². From the as-implanted samples, a visible photoluminescence band centered around 2.0 eV was observed. After postannealing at 1100°C for 90 min another visible band in the range of 1.7 eV was detected. Interestingly, with increasing thermal annealing time, a blue shift in peak energy and an intensity variation of the 1.7 eV band were observed. A possible interpretation for the observations was discussed in terms of a so-called three-region model. © 1997 American Institute of Physics.
作者：
Lan A. D.;Liu B. X.;Bai X. D.
刊名：
Journal of Applied Physics
在线出版时间：
1997

Ion-induced disconnected branching tree morphology: Correlation of fractal dimension with ion fluence

摘要：
The authors report experimental evidence of an ion-induced disconnected branching tree morphology (DBTM) as a new fractal structure. The DBTM fractal is characterised by the discontinuity of pattern components and the intrinsic branching angles. It is found that the fractal dimension of the DBTM increases with increasing ion fluence. A semi-quantitative analysis is also presented to enhance their understanding of the observed phenomenon.
作者：
Shang C. H.;Liu B. X.
刊名：
Journal of Physics Condensed Matter
在线出版时间：
1989

Self-avoiding magnetic chains formed in annealed Fe-Cu multilayers: Experiment and simulation

摘要：
Self-avoiding magnetic chains (SAMCs) were observed in annealed Fe-Cu multilayers. Scaling analyses showed that these structures were statistically self-similar and satisfied the power-law relationship well in their stretched dimension. Compared with the self-avoiding walks, the SAMCs were found to have smaller global fractal dimensionality and less geometrical entropy, which were attributed to the existing magnetic interaction and local lattice coherence during their growth, respectively. A modified tip-to-tip model was proposed to simulate the aggregation processes, and the results were in agreement with the observations.
作者：
Shang C. H.;Li H. D.;Liu B. X.
刊名：
Journal of Physics Condensed Matter
在线出版时间：
1991

AMORPHOUS FILM FORMATION BY ION MIXING IN BINARY METAL SYSTEMS.

摘要：
A structural difference rule is formulated according to which an amorphous binary alloy film is formed by ion mixing of multilayered sample when the two constituent metals are of different structure, apparently independently of their atomic sizes and electronegativities. The rule is supported by the experimental results obtained on eight selected binary metal systems, which cover all possible combinations between b. c. c. , f. c. c. and h. c. p. structures. The previous data reported in the literature also support this rule. 25 rfs.
作者：
Liu Bai Xin;Johnson W. L.;Nicolet M. A.;Lau S. S.
刊名：
Nuclear Instruments and Methods in Physics Research
在线出版时间：
1982

ION MIXING AND PHASE DIAGRAMS.

摘要：
Ion-induced mixing not only can lead to stable compound formation, but also to metastable alloy formation. In some metal-metal systems, terminal solubilities can be greatly extended by ion mixing. In other cases, where the two constituents of the system have different crystal structures, extension of terminal solubility from both sides of the phase diagram eventually becomes structurally incompatible and a glassy (amorphous) mixture can form. The composition range where this bifurcation is likely to occur is in the two-phase regions of the phase digram. These concepts are potentially useful guides in selecting metal pairs that from metallic glasses by ion mixing. In this report, phenomenological correlation between stable (and metastable) phase formation and phase diagram is discussed in terms of recent experimental data.
作者：
Lau S. S.;Liu B. X.;Nicolet M. A.
刊名：
Nuclear Instruments and Methods in Physics Research
在线出版时间：
1982

CHEMICAL EFFECTS IN ION MIXING OF TRANSITION METALS ON SiO2.

摘要：
Ion-beam mixing is investigated of Ti/SiO//2, Cr/SiO//2 and Ni/SiO//2 bilayers with 290 keV Xe. These systems were chosen in order to isolate the role of chemistry in the ion-beam mixing process. At 750 K, enhanced mixing occurs for the thermally reactive systems Ti/SiO//2 and Cr/SiO//2; however, mixing is suppressed for Ni/SiO//2. The fact that the deep tail of the metal profiles is not altered suggests that only the cascade mixing process is affected by chemical driving forces.
作者：
Banwell T.;Liu B. X.;Golecki I.;Nicolet M. A.
刊名：
Nuclear Instruments and Methods in Physics Research
在线出版时间：
1982

CEMS study of irradiation effects on the chemical bonding of SnO 2

摘要：
For a comparative study of ion irradiation effects on the chemical bonding of metal oxides, SnO 2 thin films were irradiated by 180 keV ¹²⁰ Sn ions and 80 keV N ⁺ ions, and analyzed by conversion electron Mössbauer spectroscopy (CEMS) and ESCA techniques. The results show that only ¹²⁰ Sn ion irradiation causes appreciable rupture of the SnO bonds. This phenomenon is interpreted by a proposed thermal spike model. Theoretical estimates are consistent with the experimental results. © 1987.
作者：
Li J.;Liu Bai-Xin;Li Heng-De;Wang Q.;Gao N. F.
刊名：
Nuclear Inst and Methods in Physics Research B
在线出版时间：
1987