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141.
Iron and its complexes in silicon 总被引:3,自引:0,他引:3
A.A. Istratov H. Hieslmair E.R. Weber 《Applied Physics A: Materials Science & Processing》1999,69(1):13-44
This article is the first in a series of two reviews on the properties of iron in silicon. It offers a comprehensive summary
of the current state of understanding of fundamental physical properties of iron and its complexes in silicon. The first section
of this review discusses the position of iron in the silicon lattice and the electrical properties of interstitial iron. Updated
expressions for the solubility and the diffusivity of iron in silicon are presented, and possible explanations for conflicting
experimental data obtained by different groups are discussed. The second section of the article considers the electrical and
the structural properties of complexes of interstitial iron with shallow acceptors (boron, aluminum, indium, gallium, and
thallium), shallow donors (phosphorus and arsenic) and other impurities (gold, silver, platinum, palladium, zinc, sulfur,
oxygen, carbon, and hydrogen). Special attention is paid to the kinetics of iron pairing with shallow acceptors, the dissociation
of these pairs, and the metastability of iron–acceptor pairs. The parameters of iron-related defects in silicon are summarized
in tables that include more than 30 complexes of iron as detected by electron paramagnetic resonance (EPR) and almost 20 energy
levels in the band gap associated with iron. The data presented in this review illustrate the enormous complexing activity
of iron, which is attributed to the partial or complete (depending on the temperature and the conductivity type) ionization
of iron as well as the high diffusivity of iron in silicon. It is shown that studies of iron in silicon require exceptional
cleanliness of experimental facilities and highly reproducible diffusion and temperature ramping (quenching) procedures. Properties
of iron that are not yet completely understood and need further research are outlined.
Received: 14 December 1998 / Accepted: 22 February 1999 / Published online: 26 May 1999 相似文献
142.
S.I. Anisimov N.A. Inogamov A.M. Oparin B. Rethfeld T. Yabe M. Ogawa V.E. Fortov 《Applied Physics A: Materials Science & Processing》1999,69(6):617-620
Theoretical study of laser ablation is usually based on the assumption that the vapor is an ideal gas. Its flow is described
by gas dynamics equations [1, 2]. The boundary conditions at vaporization front are derived from the solution of the Boltzmann
equation that describes the vapor flow in the immediate vicinity of the vaporizing surface (so-called Knudsen layer) [1].
This model is applicable within the range of temperatures much lower than the critical temperature of target material. In
the present work, a general case is considered when the temperature of the condensed phase is comparable to or higher than
the critical temperature. The dynamics of both condensed and gaseous phases can be described in this case by the equations
of hydrodynamics. The dynamics of vaporization of a metal heated by an ultrashort laser pulse is studied both analytically
and numerically. The analysis reveals that the flow consists of two domains: thin liquid shell moving with constant velocity,
and thick low-density layer of material in two-phase state.
Received: 2 March 1999 / Accepted: 28 May 1999 / Published online: 21 October 1999 相似文献
143.
B. Hopp T. Smausz T. Wittmann F. Ignácz 《Applied Physics A: Materials Science & Processing》2000,71(3):315-318
Comparative study of solid and liquid phase ablation on the same sample by time-resolved investigations is presented in this
paper. Polyethylene-glycol (PEG) 1000 having relatively low melting point (35 °C) was used in our experiments. By varying
the sample temperature in the 20–80 °C range we could study the ablation mechanism in both solid and liquid (below and above
the melting point) state of matter. An ArF excimer laser (λ=193 nm, FWHM=20 ns) was used for ablation at 1.95 J/cm2 fluence. Ablation processes were observed by transmission fast photographic arrangement. It was demonstrated that plasma
development and expansion (primer ablation, in 0–50 ns time range), formation and propagation parameters of shock wave and
contact front did not depend on sample temperature and state of matter. The secondary material ejection (between 1–100 μs)
showed a strong temperature dependence. Material ejection in the case of solid target occurred in the form of dense material
cloud, and in the form of splashing for liquid (molten) sample. The ejection velocity of splashed jets depended on the sample
temperature, significantly. This can be due to the change of molten PEG 1000 viscosity.
Received: 1 November 1999 / Accepted: 17 April 2000 / Published online: 5 July 2000 相似文献
144.
Formation and crystal structure of metallic inclusions in a HPHT as-grown diamond single crystal 总被引:2,自引:0,他引:2
L.-W. Yin N.-W. Wang Z.-D. Zou M.-S. Li D.-S. Sun P.-Z. Zheng Z.-Y. Yao 《Applied Physics A: Materials Science & Processing》2000,71(4):473-476
One of the most important characteristics associated with crystal growth technology is the entrapment of inclusions by the
growing crystal. Diamond single crystals prepared under high temperature-high pressure (HPHT) usually contain metallic inclusions.
In the present paper, metallic inclusions in a diamond grown from a Fe-Ni-C system using the HPHT method have been, for the
first time, systematically examined by transmission electron microscopy (TEM). Energy dispersive X-ray spectrometry (EDS)
, combined with selected area electron diffraction (SAD) patterns, has been used to identify the chemical composition and
crystal structure of the metallic inclusions. The metallic inclusions were found to be composed mainly of cubic γ-(FeNi),
face-centered cubic (FeNi)23C6, ortho-rhombic Fe3C and hexagonal Ni3C, which may have been formed through the entrapment of molten catalyst by the growth front or through reaction of the trapped
melt with contaminants in the diamond.
Received: 19 June 2000 / Accepted: 21 June 2000 / Published online: 16 August 2000 相似文献
145.
Taizo Kawauchi Katsuyuki Fukutani Shunji Kishimoto Yoshitaka Yoda 《Applied Surface Science》2009,256(4):962-964
Measurements of the internal-conversion electron emission due to the inelastic nuclear resonant excitation are reported. thin films of 20 and 1.3 nm thickness were deposited on Si(1 1 1), and the internal-conversion electrons were measured as a function of the photon energy. From the inelastic part of the spectra, the phonon density of states was obtained. Whereas the phonon density of states of 20-nm thick film resembles that of bulk -Fe, the 1.3-nm thick film revealed an obvious softening of the acoustic mode. 相似文献
146.
The propagation of acoustic wave in a two-dimensional phononic crystal of a hybrid triangular graphite array is investigated by the plane wave expansion (PWE) method. Our numerical results show that the location and width of the band gaps can be tuned by altering the radii of scatters at different positions. 相似文献
147.
X. T. Lou G. Somesfalean Z. G. Zhang S. Svanberg 《Applied physics. B, Lasers and optics》2009,94(4):699-704
The important air pollutant sulfur dioxide has a strong structured absorption band in the ultraviolet (UV) region around 300 nm.
Recently, light-emitting diodes (LEDs) with structureless emission in a band about 15-nm wide in the UV region have become
available. We demonstrate that they can be ideal sources for gas absorption measurements combined with the gas correlation
technique, where an absorption cell with an optically thick column of the gas under investigation is used for analysing the
target gas contents in a path between the LED and the measurement device. A sensitivity of 0.4 ppm sulfur dioxide was obtained
with a 19-cm optical path length and 60-s integration time. Particularly compact and cost-effective monitors especially for
industrial emissions can be envisaged. 相似文献
148.
Gain versus tuning issues to Q-switch with Yb<Superscript>3+</Superscript>:LSO and amplify broad-bandwidth pulses 总被引:1,自引:0,他引:1
We report on the development of Incoherent Broadband Cavity Enhanced Absorption Spectroscopy (IBBCEAS) using a blue light
emitting diode (LED) for the detection of NO2 in laboratory ambient air. Absorption of the oxygen collisional pair in the atmosphere was also detected in the same spectral
range. The mirror reflectivity was determined using a standard gas sample mixture of NO2, and calibrated with the help of the absorption spectrum of the oxygen collisional pair in pure oxygen at atmospheric pressure.
Optimization of the experimental parameters was investigated and is discussed in detail. For the first time in IBBCEAS involving
broadband absorption spectra, averaging time for signal-to-noise ratio enhancement has been optimized using Allan variance
plot. 18.1 ppbv NO2 in laboratory ambient air has been retrieved from the absorption spectra using differential fitting method over a 40 nm spectral
region centered at 470 nm. A minimum detection sensitivity of about 2.2 ppbv (1σ) for NO2 at atmospheric pressure has been achieved using the optimal averaging time of 100 s by means of a high finesse optical cavity
formed with two moderate reflectivity (∼99.55%) mirrors. No purging of the cavity mirrors by high purity He or N2 gas streams was necessary to prevent contamination of the mirror faces for the in situ measurements. 相似文献
149.
R. de Paiva R. A. Nogueira S. Azevedo J. R. Kaschny 《Applied Physics A: Materials Science & Processing》2009,95(3):655-659
We present first-principles’ calculations of the structural, electronic, and effective mass properties of cubic Al1−x
B
x
N ordered alloys. They are based on the density functional theory within the local density approximation, and the full-potential
linear augmented plane-wave method. From such calculations we obtain the equilibrium lattice constants, the bulk moduli, the
bandgap energies, and the effective masses along the (111), (100), and (110) directions. The results are used to give important
information on characteristics analysis of AlBN-based quantum well devices, to provide the Luttinger-like valence band parameters
and the effective masses of charge carriers, connecting the first-principles’ band calculations with effective-mass theory. 相似文献
150.
V. V. Maslyuk V. Y. Aristov O. V. Molodtsova D. V. Vyalikh V. M. Zhilin Y. A. Ossipyan T. Bredow I. Mertig M. Knupfer 《Applied Physics A: Materials Science & Processing》2009,94(3):485-489
The electronic structure and morphology of organic semiconducting cobalt-phtalocyanine (CoPc) films in situ prepared on the
Au(001)-5×20 superstructure have been studied by a combination of experimental and theoretical work. The CoPc molecular film
was characterized by photoemission spectroscopy (PES, valence band and core-level). The experimental results were simulated
and have been explained in the framework of density functional theory (DFT) calculations. The C 1s and N 1s core level spectra were analyzed by taking into account the fact that both types of atoms have different nonequivalent positions
in the molecule. And finally, the experimentally obtained electronic valence band structure of CoPc is in very good agreement
with ab initio density of state results, allowing a detailed site-specific insight into the system. 相似文献