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1.
L. K. Orlov E. A. Shteinman N. L. Ivina V. I. Vdovin 《Physics of the Solid State》2011,53(9):1798-1805
The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates
under conditions of decreased growth temperatures (T
gr ∼ 900–700°C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously,
a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium
laser (λexcit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (∼3 eV)
region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements
is split into a set of Lorentzian components. The correlation between these components and the specific features of the crystal
structure of the grown silicon carbide layers has been analyzed. 相似文献
2.
V. A. Terekhov S. Yu. Turishchev K. N. Pankov I. E. Zanin E. P. Domashevskaya D. I. Tetelbaum A. N. Mikhailov A. I. Belov D. E. Nikolichev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(5):958-967
Films obtained using molecular-beam deposition of SiO powder on c-Si (111) substrates for the purpose of SiO2 system formation with silicon nanocrystals were investigated before and after
900–1100°C annealing by photoluminescence, ultrasoft X-ray emission spectroscopy, X-ray photoelectron spectroscopy, X-ray
absorption near-edge structure spectroscopy, and X-ray diffraction. The appearance of (111)-oriented luminescent silicon nanoclusters
in considerable amounts upon annealing at T = 1000–1100°C is established in the investigated films. An anomalous phenomenon of X-ray absorption quantum yield intensity
reversal for the L
2,3 elementary silicon edge is detected. Models for this phenomenon are suggested. 相似文献
3.
Jie Feng Yin Zhang Bingchu Cai Bomy Chen 《Applied Physics A: Materials Science & Processing》2009,97(2):507-511
Undoped and N-doped Si10.5Sb89.5 films were deposited by magnetron sputtering. The X-ray diffraction spectra indicated that all of the films crystallized
into crystalline Sb with a rhombohedral structure after annealing at 280°C for 3 min. X-ray photoelectron spectroscopy analysis
indicated that the incorporated nitrogen combined with Si to form silicon nitride in the SiSb films. The changes in electrical
resistance and thermal stability of the undoped and N-doped Si10.5Sb89.5 films were investigated. The crystallization temperature increased from ∼225°C to ∼250°C when 13 at.% nitrogen was added
into the Si10.5Sb89.5 film and increased further with increasing nitrogen content. The thermal stability of the amorphous film was enhanced by
nitrogen doping. The maximum temperature for 10-year retention of amorphous state of a pure Si10.5Sb89.5 film is ∼140°C and the temperature of N-doped Si10.5Sb89.5 films is even higher, which may be helpful to improve the data retention and performance of phase-change memory in high temperature
applications. 相似文献
4.
L. K. Orlov E. A. Shteinman V. I. Vdovin 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(5):695-698
The light-emitting properties of cubic-lattice silicon carbide SiC films grown on Si(100) and Si(111) substrates with VPE
at low temperatures (T
gr ∼ 700°C) are discussed. Investigations of the grown films reveal a homogeneous nanocrystalline structure involving only the
3C-SiC phase. When the electron subsystem of the structure is excited by a He-Cd laser emitting at λexit = 325 nm, the photoluminescence (PL) spectra contain a rather strong emission band shifted by about 3 eV toward a short-wave
spectral region. At low temperatures, the PL integral curve is split into a set of Lorentz components. The relation between
these components and the peculiarities of the energy spectrum of electrons in the nanocrystalline grains of the silicon carbide
layers is discussed. 相似文献
5.
6.
在结合应变Si,高k栅和SOI结构三者的优点的基础上,提出了一种新型的高k栅介质应变Si全耗尽SOI MOSFET结构.通过求解二维泊松方程建立了该新结构的二维阈值电压模型,在该模型中考虑了影响阈值电压的主要参数.分析了阈值电压与弛豫层中的Ge组分、应变Si层厚度的关系.研究结果表明阈值电压随弛豫层中Ge组分的提高和应变Si层的厚度增加而降低.此外,还分析了阈值电压与高k栅介质的介电常数和应变Si层的掺杂浓度的关系.研究结果表明阈值电压随高k介质的介
关键词:
应变Si
k栅')" href="#">高k栅
短沟道效应
漏致势垒降低 相似文献
7.
Yoshiteru Amemiya Tomohiro Tokunaga Yuichiro Tanushi Shin Yokoyama 《Optical Review》2009,16(3):247-251
Electric-field drive optical modulators using a Si ring resonator were fabricated on silicon-on-insulator (SOI) wafers. The
fabricated resonators consisted of Si waveguides with width and thickness of 1.0 and 0.3 μm, respectively. In order to induce
the linear electro-optic (EO) effect in the Si core layer, the strain was applied by covering the layer with Si3N4 film (0.26 μm thick) deposited by low pressure chemical vapor deposition (LPCVD) at 750 °C. The vertical electric-field was
applied to the Si waveguide through the top and bottom cladding layers, and the optical output from the drop port at the resonance
wavelength was measured. At a wavelength of 1501.6 nm, the optical modulation of 33% was obtained at 200V (electric-field
at the silicon surface ∼3 × 105 V/cm, nearly the breakdown field). The resonance wavelength was shifted toward the short wavelength side by applying both
positive and negative voltages, this shift was explained by carrier concentration modulation. The linear EO effect in the
Si core layer was not observed, presumably because the strain in the Si core layer was too small. 相似文献
8.
Len’shin A. S. Kashkarov V. M. Turishchev S. Yu. Smirnov M. S. Domashevskaya E. P. 《Technical Physics》2012,57(2):305-307
The influence of natural aging on the photoluminescence intensity and the position of a photolu-minescence peak in n-type por-Si (por-Si) is studied. The variation of the phase composition and the relative content of the amorphous and oxide
phases of silicon in por-Si during aging is determined by fitting simulated spectra to experimental ultrasoft Si L
2,3 X-ray emission spectra using reference spectra. 相似文献
9.
The solid solutions La4/3−yLi3yTi2O6 (y=0.09∼0.33) have been studied by complex impedance spectroscopy, X-ray diffraction (XRD) and nuclear magnetic resonance
(NMR) methods. The ionic conductivity shows a maximum value at around y=0.21, and keeps high values at high y concentrations.
The XRD patterns show a single phase for all concentration. The crystal structure is orthorhombic with space groupPmmm for y=0.09∼0.15 and tetragonal with space groupP4/mmm for y=0.17∼0.33. The7Li static NMR spectra show a main central peak with a Lorenzian shape for y=0.09∼0.21. The central peak is divided into two
parts for y=0.23∼0.33. The narrow intense peak is a mobile component due to mobile ions, and a small broad central peak is
due to less mobile lithium ions which contribute to immobile component. The7Li MAS NMR spectra show negative chemical shifts which decrease with increasing y concentration. In this paper, we discuss
the conduction mechanism and the structure from the analysis of conductivity, lattice parameters, occupation, atomic positions
and the7Li static/MAS NMR spectra. 相似文献
10.
H. T. Chen X. L. Wu Y. Y. Zhang W. N. Su 《Applied Physics A: Materials Science & Processing》2009,97(3):725-728
Highly-pure iron powder was covered on porous silicon for fabricating semiconducting β-FeSi2 structures. X-ray diffraction and Raman scattering results confirm the formation of pure-phase β-FeSi2 after high-temperature annealing at 1100°C and then long-time persistence at 900°C. Scanning electron microscope observations
reveal that large-size (>μm) β-FeSi2 grains mainly form in the pores of porous silicon and some nanocrystals grow on local surfaces. The temperature-dependent
photoluminescence spectra disclose that the observed ∼1.54 μm emission arises from free exciton recombination, which is confirmed
via the activation energy (0.25 eV) measurement. Our method provides a way to synthesize single-phase β-FeSi2 materials. 相似文献
11.
Stuart J. Corr Lisa O'Reilly Eoghan P. Dillon Andrew R. Barron Patrick J. McNally 《Journal of Raman spectroscopy : JRS》2011,42(12):2085-2088
Poly(vinylpyrrolidone)‐stabilized silver nanoparticles deposited onto strained‐silicon layers grown on graded Si1−xGex virtual substrates are utilized for selective amplification of the Si–Si vibration mode of strained silicon via surface‐enhanced Raman scattering spectroscopy. This solution‐based technique allows rapid, highly sensitive and accurate characterization of strained silicon whose Raman signal would usually be overshadowed by the underlying bulk SiGe Raman spectra. The analysis was performed on strained silicon samples of thickness 9, 17.5 and 42 nm using a 488 nm Ar+ micro‐Raman excitation source. The quantitative determination of strained‐silicon enhancement factors was also made. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
12.
13.
14.
Samson T. H. Silalahi Q. V. Vu H. Y. Yang K. Pita Yu Mingbin 《Applied Physics A: Materials Science & Processing》2010,98(4):867-871
Controllable size of silicon (Si) nanocrystals can be achieved by a two-step rapid thermal annealing technique consisting
of rapid annealing at 1000°C in nitrogen ambient and rapid oxidation at 600–800°C of a radio frequency magnetron co-sputtered
Si-rich oxide/SiO2 superlattice structure. The photoluminescence (PL) spectra related to Si nanocrystals were observed in the visible range
(600–900 nm). After rapid oxidation, the size of the nanocrystals was reduced and the quality of the Si nanocrystal/SiO2 interface was improved, resulting in a blue shift and an increase of the PL peak intensity. Finally, annealing in air increases
the PL intensity further. 相似文献
15.
Physical mechanics of fluctuation processes in advanced submicron and decananometer MOSFETs (metal-oxide-semiconductor field-effect
transistors) including the ultra-thin film SOI (siliconon-insulator) devices using strained silicon films are reviewed. The
review is substantially based on the results obtained by the authors. It is shown that the following drastic changes occur
in the nature and parameters of noise in such devices as a result of their downscaling when the gate oxide thickness and the
channel length and width are decreased, the SOI substrates are used, the silicon film thickness is reduced, the film doping
level is varied, the strained silicon films are employed, etc. Firstly, the Lorentzian components can appear in the current
noise spectra. Those components are due to (i) electron tunneling from the valence band through the gate oxide in the SOI
MOSFETs of a sufficiently thin gate oxide (LKE-Lorentzians); (ii) Nyquist fluctuations generated in the source and drain regions
near the back Si/SiO2 interface in the SOI MOSFETs (BGI Lorentzians); (iii) electron exchange between the channel and some single trap in the gate
oxide of the transistors with sufficiently small length and width of the channel (RTS Lorentzians). Secondly, the 1/f-noise level can increase due to (i) the appearance of recombination processes near the Si/SiO2 interface activated by the currents of electron tunneling from the valence band; (ii) an increase in the trap density in
the gate oxide of the devices fabricated on the biaxially tensile-strained silicon films; (iii) the contribution of the 1/f fluctuations of the current flowing through the gate oxide as a result of electron tunneling from the conduction band. At
the same time, the 1/f-noise level may decrease due to a decrease in the trap density in the gate oxide of the transistors fabricated on the uniaxially
tensile-strained silicon films. Moreover, a 1/f
1.7 component may appear in the noise spectra for the transistors of a sufficiently thin gate oxide, whose component is due to
charge fluctuations on the defects located near the interface between the gate polysilicon and the gate oxide. 相似文献
16.
L. J. Li K. Yu H. B. Mao Z. Q. Zhu 《Applied Physics A: Materials Science & Processing》2010,99(4):865-869
By using a thermal evaporation and condensation method, Cu-doped SnO2 nanobelts were synthesized on silicon substrate. High-resolution transmission electron microscopy and energy dispersive X-ray
spectroscopy studies of Cu-doped SnO2 nanobelts demonstrate that the nanobelts are single-crystal structures and Cu is homogeneously doped into the SnO2 lattice. X-ray diffraction further confirmed the single-phase nature of these nanobelts. The photoluminescence measurements
of the nanobelts and samples annealed in oxygen were measured from 77 K to 300 K. Field-emission measurements demonstrated
that the Cu-doped nanobelts possessed good performance with a turn-on field of ∼2.9 V/μm and a threshold field of ∼4.8 V/μm. 相似文献
17.
S. Y. Huang S. Xu Q. J. Cheng J. D. Long K. Ostrikov 《Applied Physics A: Materials Science & Processing》2009,97(2):375-380
Aluminum-doped p-type polycrystalline silicon thin films have been synthesized on glass substrates using an aluminum target
in a reactive SiH4+Ar+H2 gas mixture at a low substrate temperature of 300 °C through inductively coupled plasma-assisted RF magnetron sputtering.
In this process, it is possible to simultaneously co-deposit Si–Al in one layer for crystallization of amorphous silicon,
in contrast to the conventional techniques where alternating metal and amorphous Si layers are deposited. The effect of aluminum
target power on the structural and electrical properties of polycrystalline Si films is analyzed by X-ray diffraction, Raman
spectroscopy, scanning electron microscopy and Hall-effect analysis. It is shown that at an aluminum target power of 100 W,
the polycrystalline Si film features a high crystalline fraction of 91%, a vertically aligned columnar structure, a sheet
resistance of 20.2 kΩ/□ and a hole concentration of 6.3×1018 cm−3. The underlying mechanism for achieving the semiconductor-quality polycrystalline silicon thin films at a low substrate temperature
of 300 °C is proposed. 相似文献
18.
The dependence on the energy of primary electrons of the form of the ultrasoft x-ray Si L
2,3 and Au N
6,7 emission bands is studied in Au/Si structures interacting with the oxygen in air. A method for quantitatively estimating
the phase chemical composition and its depth distribution was used, based on an analysis of the shape of the bands and employing
the most general integral form for the dependence of the intensity of the x-ray spectra on the energy of the primary electrons.
Oxidation was found to cause diffusion of silicon atoms to the surface and produce a fundamental change in the phase composition
of the structures that were studied. A characteristic feature of the structure of all the samples was the appearance on their
surface of a relatively thick layer of SiO2, whose thickness depends on the initial phase composition of the Au/Si interface.
Fiz. Tverd. Tela (St. Petersburg) 39, 2101–2105 (November 1997) 相似文献
19.
An experimental apparatus and method for investigating elastic and inelastic backscattering (180°) of low-energy (0–8 eV)
monoenergetic electrons by a solid surface are described and the first results are presented for the reflection of electrons
by samples of pure single-crystalline silicon with a polished surface (Si), doped p-type single-crystalline silicon with a porous surface (Si-p) as well as H2O and H2O2 passivated porous samples, Si-p + H2O and Si-p + H2O2. A structure due to the excitation of surface plasmons has been observed for the first time in the loss spectra. Features
corresponding to a resonance excited state of molecular nitrogen adsorbed on the surface of porous silicon have been observed
in the constant residual energy spectra.
Zh. Tekh. Fiz. 67, 103–108 (May 1997) 相似文献
20.
Woei-Shyan Lee Tao-Hsing Chen Chi-Feng Lin Jyun-Ming Chen 《Applied Physics A: Materials Science & Processing》2010,100(4):1089-1096
Thin Ni/Si films are prepared by depositing a Ni layer with a thickness of 100 nm on a Si (100) substrate. The as-deposited
thin-film specimens are indented to a maximum depth of 500 nm using a nanoindentation technique and are then annealed at temperatures
of 200°C, 300°C, 500°C and 800°C for 2 min. The microstructural changes and phases induced in the various specimens are observed
using transmission electron microscopy (TEM) and micro-Raman scattering spectroscopy (RSS). Based on the load-displacement
data obtained in the nanoindentation tests, the hardness and Young’s modulus of the as-deposited specimens are found to be
13 GPa and 177 GPa, respectively. The microstructural observations reveal that the nanoindentation process prompts the transformation
of the indentation-affected zone of the silicon substrate from a diamond cubic structure to a mixed structure comprising amorphous
phase and metastable Si III and Si XII phases. Following annealing at temperatures of 200∼500°C, the indented zone contains
either a mixture of amorphous phase and Si III and Si XII phases, or Si III and Si XII phases only, depending on the annealing
temperature. In addition, the annealing process prompts the formation of nickel silicide phases at the Ni/Si interface or
within the indentation zone. The composition of these phases depends on the annealing temperature. Specifically, Ni2Si is formed at a temperature of 200°C, NiSi is formed at a temperature of 300°C and 500°C, and NiSi2 is formed at 800°C. 相似文献