共查询到20条相似文献,搜索用时 767 毫秒
1.
M. N. Drozdov Yu. N. Drozdov E. B. Kluenkov A. Ya. Lopatin V. I. Luchin N. N. Salashchenko N. N. Tsybin L. A. Shmaenok 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(1):76-79
An analysis of the in-depth distribution of elements in annealed samples of multilayer Zr/ZrSi2 EUV filters with protective layers of MoSi2 and ZrSi2 was performed by secondary ion mass spectrometry (SIMS). The vacuum annealing of the samples was performed at temperatures
of up to 720–950°C for 3–7 h and at a residual pressure of ∼10−7 torr. It was demonstrated that MoSi2 coatings effectively inhibit the accumulation of oxygen by the heated film, which is the process that determines the optical
degradation of the filter. 相似文献
2.
S. N. Varnakov J. Bartolomé J. Sesé S. G. Ovchinnikov S. V. Komogortsev A. S. Parshin G. V. Bondarenko 《Physics of the Solid State》2007,49(8):1470-1475
The temperature dependence of the magnetization of (Fe/Si) n multilayer films with nanometer layers is investigated. The films are prepared through thermal evaporation under ultrahigh vacuum onto Si(100) and Si(111) single-crystal substrates. It is revealed that the thickness of individual iron layers in (Fe/Si) n multilayer films affects the magnetization and its temperature dependence. The inference is made that this dependence is associated with the formation of a chemical interface at the Fe-Si boundaries. The characteristics of the chemical interface in the (Fe/Si) n films are estimated. 相似文献
3.
B. M. Ayupov S. A. Prokhorova M. L. Kosinova Yu. M. Rumyantsev 《Optics and Spectroscopy》2012,112(2):201-205
The optical characteristics of nickel films deposited on Si(100) substrates by vacuum thermal evaporation have been studied.
The thickness and optical constants of the films are determined using monochromatic zero ellipsometry, while the inverse problems
are solved within the three-layer optical model of the samples. It is shown that thermal annealing leads to a change in the
optical constants of nickel films in the heating-temperature range of 500–900°C. Boron carbonitride layers deposited on silicon
substrates with a nickel sublayer are analyzed within multilayer optical models, which make it possible to determine the refractive
index and absorption coefficient distributions along the thickness of the synthesized Si(100)/Ni/BC
x
N
y
structure. 相似文献
4.
S. Muensit P. Sukwisut P. Khaenamkeaw S. B. Lang 《Applied Physics A: Materials Science & Processing》2008,92(3):659-663
Sol–gel techniques were used to prepare thin films of Pb(Zr
x
,Ti1−x
)O3 (PZT) with three different Zr/Ti ratios and a graded PZT film with three different compositional layers. A Michelson interferometer
was used to measure the thickness strains due to an applied ac electric field. Effective d
33 piezoelectric strain coefficients were computed from the experimental data. Interfacial pinning caused these coefficients
to differ from the true ones. They were corrected for the pinning using both an analytical model and finite-element analysis.
The corrected coefficients of the PZT (52/48) sample were in excellent agreement with values of bulk materials. The coefficients
of the multilayer sample were very low, probably due to insufficient poling or domain switching. 相似文献
5.
V. A. Ilyushin A. A. Velichko A. Yu. Krupin V. A. Gavrilenko A. N. Savinov A. V. Katzuba 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2016,10(6):1192-1196
The dielectric parameters of calcium fluoride films grown on the Si(100) surface by solid-phase epitaxy (group 2) and without it (group 1) are analyzed. It is established experimentally that the deposition mode of CaF2 films immediately after growth of the Si buffer layer at a substrate temperature of 530°C is not suitable for producing high-quality dielectric layers. The use of solid-phase epitaxy at the initial stage of the nucleation of CaF2 layers enables the production of single crystal uniformly thick films with high dielectric properties. 相似文献
6.
SrBi2Ta2O9(SBT)/LaNiO3(LNO)/Si and SBT/Pt/TiO2/SiO2/Si multilayers were fabricated by pulsed laser deposition. With Pt top electrodes, the measured remanent polarization (2Pr) of Pt/SBT/LNO/Si and Pt/SBT/Pt/TiO2/SiO2/Si capacitors was 6.5 C/cm2 and 5.2 C/cm2, respectively. Using LNO as both bottom electrodes and buffer layers, enhanced non-c-axis crystalline SBT films were induced, which resulted in a 2Pr greater than that of the Pt/SBT/Pt/TiO2/SiO2/Si capacitor. The hysteresis loop of the Pt/SBT/LNO/Si capacitor showed a great external-field-dependent horizontal shift. Using an electron-injection model, this dependence was addressed. The fatigue-free property of the Pt/SBT/LNO/Si capacitor was experimentally established, in that the non-volatile polarization decreased by less than 5% of the initial value after 1.44×109 switching cycles . PACS 77.84.Dy; 68.65.+g 相似文献
7.
The thermal effects produced by continuous-wave laser radiation on free-standing Si/SiO2 superlattices are studied. We compare two samples with different SiO2 layer thicknesses (2 and 6 nm) and the same Si layer thickness (2 nm). The as-prepared free-standing superlattices contain
some amount of Si nanocrystals (Si-nc). Intense laser irradiation at 488 nm of the as-prepared samples enhances the Raman
scattering of Si-nc by two orders of magnitude. This laser-induced crystallization originates from melting of Si nanostructures
in silica, which makes Si-nc better ordered and better isolated from the oxide surrounding. Continuous-wave laser control
of Si-nc stress was achieved in these samples. In the proposed model, intense laser radiation melts Si-nc, and Si crystallization
upon cooling down from the liquid phase in a silica matrix leads to compressive stress. The Si-nc stress can be tuned in the
∼3 GPa range using laser annealing below the Si melting temperature. The high laser-induced temperatures were verified with
Raman spectroscopy. The laser-induced heat leads to a strongly nonlinear rise of light emission. The light emission is also
observed in the anti-Stokes region, and its temperature dependence is practically the same for the two studied samples. The
laser-induced temperature is essentially controlled by the absorbed laser power.
PACS 78.55.-m; 78.20.-e; 68.55.-a; 78.30.-j 相似文献
8.
Meredith C. K. Sellers Edmund G. Seebauer 《Applied Physics A: Materials Science & Processing》2011,104(2):583-586
Mn-doped anatase TiO2 (Mn: 1.2, 2.4 at%) thin films were grown on Si(100) via atomic layer deposition (ALD). The synthesis utilized Ti(OCH(CH3)2)4 and H2O as ALD precursors and Mn(DPM)3 as a dopant source. X-ray photoelectron spectroscopy measurements indicate that Mn is successfully doped in the TiO2 matrix and reveal information about film composition and elemental chemical states. Microstructure, crystallinity, and density
were investigated with scanning electron microscopy, X-ray diffraction, and X-ray reflectivity. All ALD-synthesized films
exhibited room-temperature ferromagnetism; the microstructure, density, and magnetic field-dependent magnetization of the
TiO2 varied with the concentration of Mn. ALD permits precise composition and thickness control, and much higher process throughput
compared to alternative techniques. 相似文献
9.
Pb(Zr0.52Ti0.48)O3 (PZT)/LaNiO3 (LNO) thin films with highly (100) out of plane orientation were produced on SiO2/Si(100) and alkaline earth aluminosilicate glass substrates by pulsed laser deposition (PLD). Orientations of both PZT and
LNO films were evaluated using X-ray diffraction. The pure (100)-oriented PZT/LNO films were obtained under optimized deposition
conditions. Time of flight-secondary ion mass spectrometry analysis showed that LNO could effectively block interdiffusion
between the PZT films and the substrates. Fairly smooth surfaces of the PZT films with roughness of about 4 nm were observed
using an atomic force microscope. Cross sectional examination revealed that the films grew in columnar grains. The PZT films
grown on both SiO2/Si and glass substrates demonstrated very good ferroelectric characteristic at room temperature with remnant polarization
of up to 26 μC/cm2.
PACS 79.20.DS; 77.84.DY; 78.70.Ck 相似文献
10.
Shan-Tao Zhang Yi Zhang Zhen-Lin Luo Ming-Hui Lu Zheng-Bin Gu Yan-Feng Chen 《Applied Surface Science》2009,255(9):5092-5095
Bi0.8La0.2FeO3/CoFe2O4 (BLFO/CFO) multilayer thin films (totally 20 layers BLFO and 19 layers CFO) were prepared on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. X-ray diffraction and transmission electron microscope measurements show that the films are polycrystalline and consisted of multilayered structure. Ferroelectric hysteresis loops with remnant polarization and saturated polarization of 4.2 and 13.3 μC/cm2, respectively, were observed. On the other hand, the films show well-shaped magnetization hysteresis loops with saturated and remnant magnetization of 34.7 and 11.4 emu/cm3, respectively, which are significantly larger than pure BLFO thin films deposited under the same conditions. These results indicate that constructing epitaxial superlattice might be a promising way to fabricate multiferroics with improved properties. 相似文献
11.
A. S. Shulakov A. P. Braiko S. V. Bukin V. E. Drozd 《Physics of the Solid State》2004,46(10):1935-1939
The phase chemical composition of an Al2O3/Si interface formed upon molecular deposition of a 100-nm-thick Al2O3 layer on the Si(100) (c-Si) surface is investigated by depth-resolved ultrasoft x-ray emission spectroscopy. Analysis is performed using Al and Si L2, 3 emission bands. It is found that the thickness of the interface separating the c-Si substrate and the Al2O3 layer is approximately equal to 60 nm and the interface has a complex structure. The upper layer of the interface contains Al2O3 molecules and Al atoms, whose coordination is characteristic of metallic aluminum (most likely, these atoms form sufficiently large-sized Al clusters). The shape of the Si bands indicates that the interface layer (no more than 10-nm thick) adjacent to the substrate involves Si atoms in an unusual chemical state. This state is not typical of amorphous Si, c-Si, SiO2, or SiOx (it is assumed that these Si atoms form small-sized Si clusters). It is revealed that SiO2 is contained in the vicinity of the substrate. The properties of thicker coatings are similar to those of the 100-nm-thick Al2O3 layer and differ significantly from the properties of the interfaces of Al2O3 thin layers. 相似文献
12.
A. V. Boryakov S. I. Surodin D. E. Nikolichev A. V. Ershov 《Physics of the Solid State》2017,59(6):1206-1214
The chemical and the phase compositions of multilayer nanoperiodic SiO x /ZrO2 structures prepared by vacuum evaporation from separated sources and subjected to high-temperature annealing have been studied by X-ray photoelectron spectroscopy with a layer-by-layer etching. It is found that, under deposition conditions used, the silicon suboxide layers had the stoichiometric coefficient x ~1.8 and the zirconium-containing layers were the stoichiometric zirconium dioxide. It was found, using X-ray photoelectron spectroscopy, that annealing of the multilayer structures at 1000°C leads to mutual diffusion of the components and chemical interaction between ZrO2 and SiO x with predominant formation of zirconium silicate at heteroboundaries of the structures. The SiO x layers of the annealed nanostructures contained ~5 at % elemental silicon as a result of the phase separation and the formation of fine silicon nanocrystals. 相似文献
13.
N. I. Filimonova V. A. Ilyushin A. A. Velichko 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2017,11(1):130-134
The surface morphology of BaF2 epitaxial films grown by MBE (molecular beam epitaxy) in various modes on the surface of CaF2/Si(100) is investigated by AFM. The CaF2 layers on Si(100) are obtained in the high-temperature growth mode (Т S = 750°C). It is shown that the epitaxy of BaF2 at a temperature of 600°C at the initial stage of growth leads to the formation of defects such as perforations in the epitaxial film, while epitaxy at a temperature of 750°C provides a defect-free film with a surface morphology suitable for the subsequent growth of semiconductors of IV–VI type and solid solutions based on them. 相似文献
14.
A. K. Panchal D. K. Rai Meril Mathew C. S. Solanki 《Journal of nanoparticle research》2011,13(6):2469-2473
40 alternate a-Si/SiN
x
multilayer are incorporated as an absorber layer in a p–i–n solar cell. The device is fabricated using hot-wire chemical
vapor deposition (HWCVD) technique. The structure of the multilayer film is examined by high resolution transmission electron
microscopy (HR-TEM) which shows distinct formation of alternate a-Si and SiN
x
layers. The a-Si and SiN
x
layers have thickness of ~3.5 and 4 nm, respectively. The photoluminescence (PL) of multilayer film shows bandgap energy
of ~2.52 eV, is larger than that of the c-Si and a-Si. Dark and illuminated current–voltage (I–V) characterization of the ML films shows that these ML are photosensitive. In the present work, it is seen that the p–i–n
structure with i-layer as ML quantum well (QW) structures show photovoltaic effect with relatively high open-circuit voltage
(V
OC). The increment of bandgap energy in PL and high V
OC of the device is attributed to the quantum confinement effect (QCE). 相似文献
15.
X. Landreau B. Lanfant T. Merle E. Laborde C. Dublanche-Tixier P. Tristant 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,65(3):421-428
SiO
x
H
y
C
z
nanometric layers are deposited from hexamethyldisiloxane by atmospheric pressure
microwave plasma torch on Si(100) substrates submitted to temperatures varying on the
range [0 °C; 120 °C]. Atomic force microscopy (AFM) characterizations of samples grown at
intermediate substrate temperatures (~30 °C) demonstrate a layer-by-layer
growth (Frank van der Merwe growth) leading to smooth flat and compact films while films
deposited at lower and higher substrates temperatures show an island-like growth
(Volmer-Weber growth) generating a high surface roughness. Concomitantly, a detailed
infrared spectroscopy analysis of the growing films evidences structural modifications due
to changes in the bond types, Si-O-Si conformation and stoichiometry correlated with
scanning electron microscopy and AFM characterizations. Then, deposition conditions and
specific microstructure are selected with the aim of generating 3-dimensional
SiO
x
H
y
C
z
nanostructure arrays on nanoindented Si (100) templates. The first results are
discussed. 相似文献
16.
Scanning tunneling microscopy (STM) is used to study the basic laws of growth of ultrathin epitaxial CoSi2(111) films with Co coverages up to 4 ML formed upon sequential deposition of Co and Si atoms taken in a stoichiometric ratio onto the Co–Si(111) surface at room temperature and subsequent annealing at 600–700°C. When the coverage of Co atoms is lower than ~2.7 ML, flat CoSi2 islands up to ~3 nm high with surface structure 2 × 2 or 1 × 1 grow. It is shown that continuous epitaxial CoSi2 films containing 3–4 triple Si–Co–Si layers grow provided precise control of deposition. CoSi2 films can contain inclusions of the local regions with (2 × 1)Si reconstruction. At a temperature above 700°C, a multilevel CoSi2 film with pinholes grows because of vertical growth caused by the difference between the free energies of the CoSi2(111) and Si(111) surfaces. According to theoretical calculations, structures of A or B type with a coordination number of 8 of Co atoms are most favorable for the CoSi2(111)2 × 2 interface. 相似文献
17.
Wang Changzhou Zhai Jiwei Song Zhitang Shang Fei Yao Xi 《Applied Physics A: Materials Science & Processing》2011,103(1):193-198
Phase-change behavior in Si/Sb80Te20 nanocomposite multilayer films were investigated by utilizing in situ resistance measurements. It was found that the crystallization
temperature increased firstly with increasing Si layer thickness within the multilayer films, and then remained almost unchanged
at 170°C. The multilayer films have the merits of both good thermal stability and fast phase-change speed. An increase in
crystallization temperature by around 95°C was observed for the multilayer films when the Sb80Te20 layer thickness was reduced to 3 nm. Cross-sectional transmission electron microscopy (TEM) observations revealed that Si/Sb80Te20 nanocomposite multilayer films had layered structures with clear interfaces. The reversible phase change between set and
reset states was verified in phase-change random access memory (PCRAM) cell based on [Si (1 nm)/Sb80Te20 (5 nm)]17 multilayer film. 相似文献
18.
D. Do S. S. Kim S. W. Yi J. W. Kim 《Applied Physics A: Materials Science & Processing》2009,94(3):697-701
Ferroelectric and dielectric properties of bilayered ferroelectric thin films, SrBi4Ti4O15 grown on Bi4Ti3O12, were investigated. The thin films were annealed at 700°C under oxygen atmosphere. The bilayered thin films were prepared
on a Pt(111)/Ti/SiO2/Si substrate by a chemical solution deposition method. The dielectric constant and dielectric loss of the bilayered thin
films were 645 and 0.09, respectively, at 100 kHz. The value of remnant polarization (2P
r) measured from the ferroelectric thin film capacitors was 60.5 μC/cm2 at electric field of 200 kV/cm. The remnant polarization was reduced by 22% of the initial value after 1010 switching cycles. The results showed that the ferroelectric and dielectric properties of the SrBi4Ti4O15 on Bi4Ti3O12 ferroelectric thin films were better than those of the SrBi4Ti4O15 grown on a Pt-coated Si substrate suggesting that the improved properties may be due to the different nucleation and growth
kinetics of SrBi4Ti4O15 on the c-axis-oriented Bi4Ti3O12 layer or on the Pt-coated Si substrate. 相似文献
19.
I. V. Babkina K. S. Gabriel’s T. I. Epryntseva O. V. Zhilova V. A. Makagonov A. V. Sitnikov P. M. Hlopovskikh 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(9):1168-1171
The effect heat treatment has on the electrotransport mechanisms in films of ZnO and In2O3, and in a multilayer (In2O3/ZnO)83 structure obtained via ion-beam sputtering, is studied. It is shown that there is a mechanism of weak electron localization in the In2O3 and (In2O3/ZnO)83 samples. The relaxation processes that occur during the heat treatment of In2O3 films are found to increase the length of elastic electron scattering, but to reduce this parameter in multilayer heterostructures. 相似文献
20.
M. Modreanu M. Gartner E. Aperathitis N. Tomozeiu M. Androulidaki D. Cristea Paul Hurley 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):461
Structures containing silicon nanocrystals (nc-Si) are very promising for Si-based light-emitting devices. Using a technology compatible with that of silicon, a broader wavelength range of the emitted photoluminescence (PL) was obtained with nc-Si/SiO2 multilayer structures. The main characteristic of these structures is that both layers are light emitters. In this study we report results on a series of nc-Si/SiO2 multilayer periods deposited on 200 nm thermal oxide SiO2/Si substrate. Each period contains around 10 nm silicon thin films obtained by low-pressure chemical vapour deposition at T=625°C and 100 nmSiO2 obtained by atmospheric pressure chemical vapour deposition T=400°C. Optical and microstructural properties of the multilayer structures have been studied by spectroscopic ellipsometry (using the Bruggemann effective medium approximation model for multilayer and multicomponent films), FTIR and UV–visible reflectance spectroscopy. IR spectroscopy revealed the presence of SiOx structural entities in each nc-Si/SiO2 interface. Investigation of the PL spectra (using continuous wave-CW 325 nm and pulsed 266 nm laser excitation) has shown several peaks at 1.7, 2, 2.3, 2.7, 3.2 and 3.7 eV, associated with the PL centres in SiO2, nc-Si and Si–SiO2 interface. Their contribution to the PL spectra depends on the number of layers in the stack. 相似文献