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1.
N+BF<Subscript>2</Subscript> and N+C+BF<Subscript>2</Subscript> high-dose co-implantation in silicon
L. Barbadillo M. Cervera M.J. Hernández P. Rodríguez J. Piqueras S.I. Molina A. Ponce F.M. Morales 《Applied Physics A: Materials Science & Processing》2003,76(5):791-800
Nitrogen and boron BF2, and nitrogen, carbon, and boron BF2 high-dose (6×1016–3×1017 cm-2) co-implantation were performed at energies of about 21–77 keV. Subsequent high-temperature annealing processes (600, 850,
and 1200 °C) lead to the formation of three and two surface layers respectively. The outer layer mainly consists of polycrystalline
silicon and some amorphous material and Si3N4 inclusions. The inner layer is highly defective crystalline silicon, with some inclusions of Si3N4 too. In the N+B-implanted sample the intermediate layer is amorphous. Co-implantation of boron with nitrogen and with nitrogen
and carbon prevents the excessive diffusivity of B and leads to a lattice-parameter reduction of 0.7–1.0%.
Received: 10 January 2002 / Accepted: 30 May 2002 / Published online: 4 November 2002
RID="*"
ID="*"Corresponding author. Fax: +34-91/3974895; E-mail: Lucia.Barbadillo@uam.es 相似文献
2.
T. Ohtsubo T. Azuma M. Takaura T. Higashiguchi S. Kubodera W. Sasaki 《Applied Physics A: Materials Science & Processing》2003,76(2):139-141
We have demonstrated the non-thermal removal of oxygen atoms from an oxidized silicon surface (SiO2) on a silicon wafer by the use of a low-power (0.3 mW cm-2) incoherent vacuum ultraviolet (VUV) light source at 126 nm. X-ray photoelectron spectroscopy (XPS) has shown that a maximum
Si concentration of 80% appears at the surface after a 20-h irradiation with 9.8 eV photons, as a result of oxygen removal
from the SiO2 matrix. The surface morphology, however, indicates no damage or melting on the surface even after the irradiation.
Received: 15 April 2002 / Accepted: 17 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Permanent address: Nano-Tech Photon Inc., Shimotomita 4132-1, Shintomi, Miyazaki, 889-1404, Japan
RID="**"
ID="**"Corresponding author. Fax: +81-985/583-899, E-mail: kubodera@opt.miyazaki-u.jp 相似文献
3.
M. Mamor Y. Fu O. Nur M. Willander S. Bengtsson 《Applied Physics A: Materials Science & Processing》2001,72(5):633-637
We investigate, both experimentally and theoretically, current and capacitance (I–V/C–V) characteristics and the device performance
of Si/SiO2/Si single-barrier varactor diodes (SBVs). Two diodes were fabricated with different SiO2 layer thicknesses using the state-of-the-art wafer bonding technique. The devices have very low leakage currents (about 5×10-2 and 1.8×10-2 mA/mm2) and intrinsic capacitance levels of typically 1.5 and 50 nF/mm2 for diodes with 5-nm and 20-nm oxide layers, respectively. With the present device physical parameters (25-mm2 device area, 760-μm modulation layer thickness and ≈1015-cm-3 doping level), the estimated cut-off frequency is about 5×107 Hz. With the physical parameters of the present existing III–V triplers, the cut-off frequency of our Si-based SBV can be
as high as 0.5 THz.
Received: 9 February 2001 / Accepted: 9 February 2001 / Published online: 23 March 2001 相似文献
4.
K.H. Heinig T. Müller B. Schmidt M. Strobel W. Möller 《Applied Physics A: Materials Science & Processing》2003,77(1):17-25
We have investigated the synthesis of nanostructures, as well as the control of their size and location by means of ion beams.
The phase separation and interface kinetics under ion irradiation give new possibilities for controlling the growth of nanostructures.
Additionally, the chemical decomposition of the host matrix by collisional mixing can contribute to the self-organization
of nanostructures, especially at interfaces. It is shown how collisional mixing during ion implantation affects nanocrystal
(NC) synthesis and how ion irradiation through NCs modifies their size and size distribution. An analytical expression for
solute concentration around an ion-irradiated NC was found, which may be written like the well-known Gibbs–Thomson relation.
However, parameters have modified meanings, which has a significant impact on the evolution of NC ensembles. “Inverse Ostwald
ripening” of NCs, resulting in an unimodal NC size distribution, is predicted, which has been confirmed experimentally for
Au NCs in SiO2 and by kinetic lattice Monte Carlo simulations. At interfaces, the same ion-irradiation-induced mechanism may result in self-organization
of NCs into a thin δ-layer. Collisional decomposition of SiO2 may enhance the NC δ-layer formation in SiO2 at the Si/SiO2 interface. The distance of the self-organized NC δ-layer from the SiO2/Si interface renders the structure interesting for non-volatile memory applications.
Received: 11 November 2002 / Accepted: 12 November 2002 / Published online: 4 April 2003
RID="*"
ID="*"Corresponding author. Fax: +49-351-260-3285, E-mail: K.-H.Heinig@fz-rossendorf.de 相似文献
5.
F.C. Fonseca G.F. Goya R.F. Jardim N.L.V. Carreño E. Longo E.R. Leite R. Muccillo 《Applied Physics A: Materials Science & Processing》2003,76(4):621-623
Ni nanoparticles embedded in an amorphous SiO2 matrix were produced by a modified sol–gel method. This method resulted in nanocomposites with a controlled size distribution
and good dispersion of the metallic particles. The particle-size distributions were found to have an average radius of ∼3 nm,
as inferred from transmission electron microscopy, X-ray-diffraction analysis, and magnetic measurements. Magnetic characterizations
revealed that samples exhibit superparamagnetic behavior above the blocking temperature TB, 20 K≤TB≤40 K, and absence of a shift along the field axis on hysteresis loops measured at T≤TB, indicating that the metallic nanoparticles are also free from an oxide layer.
Received: 7 October 2002 / Accepted: 9 October 2002 / Published online: 8 January 2003
RID="*"
ID="*"Corresponding author. Fax: +55-11/3091-6984, E-mail: rjardim@if.usp.br 相似文献
6.
The kinetics of growth, composition and electronic structure of thin oxide films formed by reactive ion beam mixing (IBM)
of Ni/Al interfaces bombarded with low-energy (3-keV) O2+\mathrm{O}_{2}^{+} ions have been studied at room temperature using X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy
and factor analysis. Initially, NiO species are formed but, later, with increasing ion dose, Ni–Al mixed oxide species appear
due to Al incorporation in the near-surface region. These changes are accompanied by a slight increase of the oxygen concentration
and a decrease of the Ni/Al ratio in the thin oxide films formed. Angle-resolved X-ray photoelectron spectroscopy shows that
Ni–Al mixed oxide species are located nearer the surface than NiO species. Experimental results have been compared with Monte
Carlo TRIDYN simulations, suggesting that processes driven by residual defects or the reaction with oxygen predominate over
pure ballistic mechanisms during reactive IBM of Ni/Al interfaces. 相似文献
7.
G.F. Cerofolini 《Applied Physics A: Materials Science & Processing》2003,76(1):49-52
The thermodynamic and kinetic stabilities of the Si–H bonds at the Si–SiO2 interface are studied on the basis of high-level quantum-mechanical calculations in the framework of density-functional theory.
In the absence of an applied electric field, the silanic bond is shown to be stable with respect to both hole capture from
the top of the silicon valence band and electron loss to the bottom of the silicon conduction band, but unstable with respect
to hole capture from the top of the SiO2 conduction band. The positively charged hydrogen does not shift spontaneously to protonate a neighbouring siloxanic bridge
unless it contains one adsorbed water molecule at least. The protonated siloxanic site thus formed may restore the original
silanic site (via simultaneous electron capture from the conduction band and hydron shift to silicon) but also evolve spontaneously
to a hydrogen atom via simple electron capture.
Received: 2 November 2001 / Accepted: 6 January 2002 / Published online: 20 March 2002 / Published online: 20 March 2002
RID="*"
ID="*"Also at: STMicroelectronics, 20041 Agrate MI, Italy (E-mail: gianfranco.cerofolini@st.com) 相似文献
8.
Crunteanu A. Jänchen G. Hoffmann P. Pollnau M. Buchal C. Petraru A. Eason R.W. Shepherd D.P. 《Applied Physics A: Materials Science & Processing》2003,76(7):1109-1112
We present a method for the selective two- and three-dimensional patterning of sapphire using light ion-beam implantation
to generate severe lattice damage to depths exceeding 1 μm and subsequent selective wet chemical etching of the damaged regions
by hot H3PO4. C-cut sapphire crystals were implanted through contact masks using ion fluences of 1×1016 to 5×1017 He+/cm2 and energies up to 400 keV. The etching process is characterized by a high selectivity and a rate of approximately 19 nm/min.
Whereas an implantation that produces a continuously damaged pathway results in complete etching from the surface, sole in-depth
implantation using only high-energy ions leads to under-etching of the crystalline surface layer. By a combination of these
processes we have fabricated three-dimensional structures such as channels and bridges in sapphire.
Received: 14 October 2002 / Accepted: 15 October 2002 / Published online: 26 February 2003
RID="*"
ID="*"Corresponding author. Fax +41-21/693-3701, E-mail: aurelian.crunteanustanescu@epfl.ch 相似文献
9.
X. Liu Q. Lu P. Liu M. Zhao Z. Wang M. Ying F. Li L. Qin 《Applied Physics A: Materials Science & Processing》2003,76(2):273-275
Range distributions for bismuth ions implanted in AgGaSe2 in the energy range 80–300 keV were investigated by using 2.1-MeV He2+ Rutherford backscattering spectrometry (RBS). A convolution calculation method was used to extract the true distributions
of bismuth from the measured RBS spectra. The range distribution parameters, Rp and ΔRp, were obtained and compared with those obtained from Monte Carlo simulation. The experimental Rp values agree with the Monte Carlo simulation values very well, but the experimental ΔRp values are systematically larger than those from the theoretical simulation.
Received: 28 January 2002 / Accepted: 11 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +86-531/856-5167, E-mail: xdliu@sdu.edu.cn 相似文献
10.
The electronic energy loss of swift heavy ions (MeV/amu) within a solid results in a highly excited cylindrical zone of some
nm in diameter, within which all atoms may be in motion for some tens of ps (transient local melting). After cooling down,
a defect-rich or even amorphous latent track is left in many cases, especially in insulating materials. The resulting property
alterations (density, micro-structure, morphology, phase composition, etc.) have been investigated for many bulk materials,
while only very few experiments have been carried out with thin-film systems. In the present paper, a summary will be given
of our studies on the transport of matter in thin-film packages induced by irradiation with high-energy ions. These is, on
the one hand, atomic mixing at the interfaces, which is especially pronounced in ceramic systems and which seems to occur
by interdiffusion in the molten ion track. On the other hand, we have discovered a self-organisation phenomenon in swift-heavy-ion-irradiated
NiO layers, which at low fluences first showed periodic cracking perpendicular to the projected beam direction. After application
of high fluences, the NiO layer was reorganised in 100-nm-thick and 1-μm-high NiO lamellae of the same separation distance
(1–3 μm) and orientation as found for the cracks. Both effects can be attributed to transient melting of the material surrounding
the ion trajectory.
Received: 11 November 2002 / Accepted: 12 November 2002 / Published online: 4 April 2003
RID="*"
ID="*"Corresponding author. Fax: +49-711/6853-866, E-mail: bolse@ifs.physik.uni-stuttgart.de 相似文献
11.
J.-Y. Zhang Y.-H. Ye X.-L. Tan X.-M. Bao 《Applied Physics A: Materials Science & Processing》2000,71(3):299-303
Luminescent SiO2 films containing Ge nanocrystals are fabricated by using Ge ion implantation, and metal–oxide–semiconductor structures employing
these films as the active layers show yellow electroluminescence (EL) under both forward and reverse biases. The EL spectra
are strongly dependent on the applied voltage, but slightly on the mean size of Ge nanocrystals. When the forward bias increases
towards 30 V, the EL spectral peak shifts from 590 nm to 485 nm. It is assumed that the EL originates from the recombination
of injected electrons and holes in Ge nanocrystals near the Si/SiO2 interface, or through luminescent centers in the SiO2 matrix near the SiO2/metal interface. The mismatch of the injection amounts between holes and electrons results in the low EL efficiency.
Received: 28 February 2000 / Accepted: 28 March 2000 / Published online: 5 July 2000 相似文献
12.
G.W. Meng X.S. Peng Y.W. Wang C.Z. Wang X.F. Wang L.D. Zhang 《Applied Physics A: Materials Science & Processing》2003,76(1):119-121
Aligned SiOx nanowire arrays standing on a Si substrate were successfully synthesized using a simple method by heating a single-crystalline
Si slice covered with SiO2 nanoparticles at 1000 °C in a flowing Ar atmosphere. The SiOx nanowire arrays were characterized by scanning electron microscopy and transmission electron microscopy. The SiOx nanowires become progressively thinner from bottom to top. The formation process of the SiOx nanowire arrays is closely related to a vapor–solid mechanism. Room-temperature photoluminescence measurements under excitation
at 260 nm showed that the SiOx nanowire arrays had a strong blue–green emission at 500 nm (about 2.5 eV), which may be related to oxygen defects.
Received: 29 April 2002 / Accepted: 30 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +86-551-559-1434, E-mail: gwmeng@mail.issp.ac.cn 相似文献
13.
Oleg A. Yeshchenko Igor. M. Dmitruk Andriy M. Dmytruk 《Journal of Physics and Chemistry of Solids》2008,69(7):1615-1622
Nickel nanoparticles were grown in silica glass by annealing of the sol-gel prepared silicate matrices doped with nickel nitrate. TEM characterization of Ni/SiO2 glass proves the formation of isolated spherical nickel nanoparticles with mean sizes 6.7 and 20 nm depending on annealing conditions. The absorption and photoluminescence spectra of Ni/SiO2 glasses were measured. In the absorption spectra, we observed the band related to the surface plasmon resonance (SPR) in Ni nanoparticles. The broadening of SPR was observed with decrease of Ni nanoparticle size. The width of the surface plasmon band decreases 1.5 times at the lowering of temperature from 293 to 2 K because of strong electron-phonon interaction. The spectra proved the creation of nickel oxide NiO clusters and Ni2+ ions in silica glass as well. 相似文献
14.
Group-IV nanocluster formation by ion-beam synthesis 总被引:1,自引:0,他引:1
W. Skorupa L. Rebohle T. Gebel 《Applied Physics A: Materials Science & Processing》2003,76(7):1049-1059
A short review of our investigations devoted to the use of ion-beam-synthesized nanoclusters for silicon-based light emission
and nonvolatile memory effects is presented. Blue-violet light emission is demonstrated based on Ge-implanted silicon dioxide
layers thermally grown on silicon substrates. This version of silicon-based light emission relies on Ge-related defects in
the amorphous ≡Si–O–Si≡ network. The photoluminescence and electroluminescence are excited by a singlet S0–S1 transition of a neutral oxygen vacancy and by electron injection from the silicon substrate into the silicon dioxide layer,
respectively. Whereas the photoluminescence excitation is a well-known mechanism, for the case of electroluminescence an interpretation
was performed for the first time in the course of our studies. It was found that the most probable way to excite luminescence
centers is the impact excitation by hot electrons. Whereas the injection is explained by trap-assisted tunneling of electrons
from the substrate into the oxide, the electrons will be transported via traps or in the SiO2 conduction band. The application of the silicon-based light-emitting devices for an integrated optocoupler arrangement is
described. Another application of nanoclusters is based on the investigation of thin Si-implanted silicon dioxide layers for
nonvolatile memory devices. First promising results demonstrate that the observed programming window can reach several volts
and the devices exhibit excellent retention behavior. A 256 K-nv-SRAM is demonstrated showing a programming window of >1 V
for write pulses of 12 V/8 ms.
Received: 21 August 2002 / Accepted: 21 August 2002 / Published online: 12 February 2003
RID="*"
ID="*"Corresponding author. Fax: +49-351/260-3411, E-mail: w.skorupa@fz-rossendorf.de 相似文献
15.
16.
G. Held 《Applied Physics A: Materials Science & Processing》2003,76(5):689-700
The mutual influence of surface geometry (e.g. lattice parameters, morphology) and electronic structure is discussed for Cu-Ni
bimetallic (111) surfaces. It is found that on flat surfaces the electronic d-states of the adlayer experience very little
influence from the substrate electronic structure which is due to their large separation in binding energies and the close
match of Cu and Ni lattice constants. Using carbon monoxide and benzene as probe molecules, it is found that in most cases
the reactivity of Cu or Ni adlayers is very similar to the corresponding (111) single crystal surfaces. Exceptions are the
adsorption of CO on submonolayers of Cu on Ni(111) and the dissociation of benzene on Ni/Cu(111) which is very different from
Ni(111). These differences are related to geometric factors influencing the adsorption on these surfaces.
Received: 26 August 2002 / Accepted: 4 September 2002 / Published online: 5 February 2003
RID="*"
ID="*"Corresponding author. Fax: +44-1223/76-2829, E-mail: gh10009@cam.ac.uk [+1pt] Present address: University of Cambridge,
Lensfield Road, Department of Chemistry, Cambridge CB2 1EW, UK 相似文献
17.
D. Rudolph D. Weisshaar F. Cristancho J. Eberth C. Fahlander O. Iordanov S. Skoda Ch. Teich O. Thelen H.G. Thomas 《The European Physical Journal A - Hadrons and Nuclei》1999,6(4):377-380
The neutron g
9/2 single-particle state in 57Ni has been unambiguously identified in a combined measurement of the linear polarization, angular distribution, and angular
correlation of γ rays following the fusion-evaporation reaction 28Si(32S,2pn)57Ni at a beam energy of 90 MeV. The linear polarization was measured with a Euroball cluster detector and a prototype of an encapsulated six-fold segmented hexaconical Ge-detector. The spin of the 3701 keV
level in 57Ni was confirmed to be I= 9/2 and its parity determined to be positive.
Received: 24 September 1999 / Revised version: 22 October 1999 相似文献
18.
A.V. Karabutov V.D. Frolov E.N. Loubnin A.V. Simakin G.A. Shafeev 《Applied Physics A: Materials Science & Processing》2003,76(3):413-416
Low-threshold field electron emission (FEE) is reported for periodic arrays of micro-tips produced by laser ablation of Si
wafers. The best samples show emission at threshold fields as low as 4–5 V/μm for n-type Si substrates and of 1–2 V/μm for
p-doped Si substrates, as measured with a flat-screen technique. Auger electron spectroscopy and X-ray electron spectroscopy
reveal island-like deviation of the SiO2 stoichiometry on the tip surfaces, with lateral dimensions of less than 100 nm. Microscopic studies using a special field-emission
STM show that the emission originates from well-conducting regions of sub-micron size. The experimental data suggest FEE from
the tip arrays by a geometric field enhancement of both the individual micro-tip and the narrow conducting channels in the
tip body.
Received: 3 May 2002 / Accepted: 1 July 2002 / Published online: 28 October 2002
RID="*"
ID="*"Corresponding author. Fax: +7-095/135-82-34, E-mail: shafeev@kapella.gpi.ru 相似文献
19.
H. F. Kappert K. F. Heidemann D. Eichholz E. te Kaat W. Tothemund 《Applied Physics A: Materials Science & Processing》1980,21(2):151-158
Oxygen profiles in silicon implanted with energies between 2 and 20 MeV by means of a Tandem accelerator have been investigated with a microprobe after bevelling the sample surface. It is shown that the measured profiles correspond to the implantation profiles when the microprobe is operated with a well focussed 2 keV electron beam. The projected ion ranges and the profiles thus obtained are compared with theoretical profiles which have been calculated by a Monte Carlo simulation of the stopping procedure. Takingk=1.30k LSS for the electronic stopping coefficient in the LSS region up to 2.55 MeV and a constant value of 162 eV/Å for the electronic stopping at higher energies the calculation yields satisfactory range estimates, whereas the range straggling is systematically too small up to 13% in comparison with the experimental results. 相似文献
20.
T.V. Dolgova V.G. Avramenko A.A. Nikulin G. Marowsky A.F. Pudonin A.A. Fedyanin O.A. Aktsipetrov 《Applied physics. B, Lasers and optics》2002,74(7-8):671-675
Size effects in the resonant nonlinear optical response of amorphous Si/SiO2 multiple quantum wells (MQW) are studied by second-harmonic generation (SHG) spectroscopy in a spectral interval of second-harmonic
photon energies from 2.5 to 3.4 eV. The sensitivity of SHG spectroscopy to thickness-dependent electronic structure (sub-band
energy position and density of states line shape) of MQW is demonstrated. A monotonic red shift of central energies of SHG
resonances by 120 m eV upon increase of the well thickness from 2.5 to 10 ? is observed. This is interpreted as a size dependence
of the position of singularities in the combined density of states for a 2D gas of electrons moving in an effective potential
well. It is shown that, for agreement with experiment, the simplest (rectangular) shape of the well should be modified in
order to take into account the lattice-potential distortion at the interfaces.
Received: 16 October 2001 / Revised version: 16 April 2002 / Published online: 6 June 2002 相似文献