共查询到20条相似文献,搜索用时 15 毫秒
1.
Mathias Mews Caspar Leendertz Michael Algasinger Svetoslav Koynov Lars Korte 《固体物理学:研究快报》2014,8(10):831-835
Excellent passivation of black silicon surfaces by thin amorphous silicon layers deposited with plasma enhanced chemical vapor deposition is demonstrated. Minority charge carrier lifetimes of 1.3 milliseconds, enabling an implied open‐circuit voltage of 714 mV, were achieved. The influence of amorphous silicon parasitic epitaxial growth and thickness, as well as of the texture depth is investigated. Furthermore, quantum efficiency gains for wavelengths above 600 nm, as compared to random textured solar cells, are demonstrated in 17.2% efficient amorphous–crystalline silicon heterojunction solar cells with black silicon texture. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
2.
Amorphous layers produced at the surface of iron by B+ and C+ implantation (50 kV, 1×1018 ions cm−2) were analyzed by CEMS. The CEM spectrum of B+ implanted layer was composed of broad doublet and sextet. Spread hyperfine field distribution, P(H), indicates the formation
of extremely disordered FeB layer. Annealing at 400°C brought about precipitation of FeB, which was converted to Fe2B by annealing at 500°C.
The P(H) for C+ implanted iron was resolved to 3 subpeaks with H values of 11.0, 18.0 and 22.5 T. The amorphous FeC phase was strongly correlated
to crystalline Fe5C2 and Fe2C, which precipitated at 300°C and were transformed into Fe3C at 500°C. The amorphous layer disappeared by annealing at 600°C. 相似文献
3.
Properties of reactively sputtered W–B–N thin film as a diffusion barrier for Cu metallization on Si
L. C. Leu D. P. Norton L. McElwee-White T. J. Anderson 《Applied Physics A: Materials Science & Processing》2009,94(3):691-695
Thin films of W–B–N (10 nm) have been evaluated as diffusion barriers for Cu interconnects. The amorphous W–B–N thin films
were prepared at room temperature via reactive magnetron sputtering using a W2B target at various N2/(Ar + N2) flow ratios. Cu diffusion tests were performed after in-situ deposition of 200 nm Cu. Thermal annealing of the barrier stacks
was carried out in vacuum at elevated temperatures for one hour. X-ray diffraction patterns, sheet resistance measurement,
cross-section transmission electron microscopy images, and energy-dispersive spectrometer scans on the samples annealed at
500°C revealed no Cu diffusion through the barrier. The results indicate that amorphous W–B–N is a promising low resistivity
diffusion barrier material for copper interconnects. 相似文献
4.
Hopp B. Smausz T. Kresz N. Nagy P.M. Juhász A. Ignácz F. Márton Z. 《Applied Physics A: Materials Science & Processing》2003,76(5):731-735
Allergic-type diseases are current nowadays, and they are frequently caused by certain metals. We demonstrated that the metal
objects can be covered by Teflon protective thin layers using a pulsed laser deposition procedure. An ArF excimer laser beam
was focused onto the surface of pressed PTFE powder pellets; the applied fluences were 7.5–7.7 J/cm2. Teflon films were deposited on fourteen-carat gold, silver and titanium plates. The number of ablating pulses was 10000.
Post-annealing of the films was carried out in atmospheric air at oven temperatures between 320 and 500 °C. The thickness
of the thin layers was around 5 μm. The prepared films were granular without heat treatment or after annealing at a temperature
below 340 °C. At 360 °C a crystalline, contiguous, smooth, very compact and pinhole-free thin layer was produced; a melted
and re-solidified morphology was observed above 420 °C. The adhesion strength between the Teflon films and the metal substrates
was determined. This could exceed 1–4 MPa depending on the treatment temperature. It was proved that the prepared Teflon layers
can be suitable for prevention of contact between the human body and allergen metals and so for avoidance of metal allergy.
Received: 12 June 2002 / Accepted: 13 June 2002 / Published online: 4 November 2002
RID="*"
ID="*"Corresponding author. E-mail: bhopp@physx.u-szeged.hu 相似文献
5.
Y. W. Li Z. G. Hu F. Y. Yue W. Z. Zhou P. X. Yang J. H. Chu 《Applied Physics A: Materials Science & Processing》2009,95(3):721-725
(La0.5Sr0.5)CoO3 (LSCO) thin films have been fabricated on silicon substrate by the pulsed laser deposition method. The effects of substrate
temperature and post-annealing condition on the structural and electrical properties are investigated. The samples grown above
650°C are fully crystalline with perovskite structure. The film deposited at 700°C has columnar growth with electrical resistivity
of about 1.99×10−3 Ω cm. The amorphous films grown at 500°C were post-annealed at different conditions. The sample post-annealed at 700°C and
10−4 Pa has similar microstructure with the sample in situ grown at 700°C and 25 Pa. However, the electrical resistivity of the
post-annealed sample is one magnitude higher than that of the in situ grown sample because of the effect of oxygen vacancy.
The temperature dependence of resistivity exhibits semiconductor-like character. It was found that post-annealing by rapid
thermal process will result in film cracks due to the thermal stress. The results are referential for the applications of
LSCO in microelectronic devices. 相似文献
6.
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
7.
S. Ağan A. Çelik-Aktaş J.M. Zuo A. Dana A. Aydınlı 《Applied Physics A: Materials Science & Processing》2006,83(1):107-110
Germanosilicate layers were grown on Si substrates by plasma enhanced chemical vapor deposition (PECVD) and annealed at different temperatures ranging from 700–1010 °C for durations of 5 to 60 min. Transmission electron microscopy (TEM) was used to investigate Ge nanocrystal formation in SiO2:Ge films. High-resolution cross section TEM images, electron energy-loss spectroscopy and energy dispersive X-ray analysis (EDX) data indicate that Ge nanocrystals are present in the amorphous silicon dioxide films. These nanocrystals are formed in two spatially separated layers with average sizes of 15 and 50 nm, respectively. EDX analysis indicates that Ge also diffuses into the Si substrate. PACS 68.73.Lp; 61.46.Hk; 61.46.-w; 68.65.Hb; 61.82.Rx 相似文献
8.
The X-ray pattern of ice recorded at −10°C reveals, along with the reflexes of a hexagonal phase, intense diffuse X-ray scattering,
testifying to the presence of a noncrystalline phase in the sample. Heating of ice to a temperature close to the melting point
leads to almost complete decomposition of the crystalline phase. As this takes place, intense diffuse X-ray scattering with
a maximum at 2Θ of 23°C appears in the diffraction pattern, which is typical for a metastable amorphous phase. The first maximums
of the radial distribution function for the metastable amorphous phase of ice appear to be close in their positions to the
first radii of the hexagonal phase coordination spheres. 相似文献
9.
D. Wörle H. Grünleitner V. Demuth C. Kumpf H.P. Strunk E. Burkel M. Schulz 《Applied Physics A: Materials Science & Processing》1998,66(6):629-637
The electro-optical properties of the films are studied by measuring the infrared optical absorption and the yield of hole
photoemission across the Schottky barrier to the p-Si substrate. The Schottky barrier height of the amorphous a-IrSi to the
valence band of Si is 0.17–0.18 eV. The barrier height of the polycrystalline c-IrSi depends on the degree of texturing of
the silicide; the Schottky barrier height increases from 0.14 eV to 0.18 eV when the substrate temperature is increased from
room temperature to 400 °C during the Ir metal deposition prior to the 500 °C silicidation. The non-linearity of the photoemission
yield observed for the amorphous a-IrSi in the Fowler plot is due to an energy-dependent photon absorption of these amorphous
films. An evaluation of the scattering events in the metal films shows that the mean free path for inelastic scattering is
λin=500 nm in the amorphous a-IrSi which is one order of magnitude larger than that in the crystalline c-IrSi. The mean free
path for quasi-elastic scattering λqe=0.3 nm, of the amorphous a-IrSi is in the order of the interatomic distance, indicating a localization of the electronic
states.
Received: 14 November 1997/Accepted: 12 January 1998 相似文献
10.
《Applied Surface Science》2002,185(3-4):243-247
By using RF plasma-enhanced chemical vapor deposition, amorphous carbon films were grown in pure methane plasma. Field emission of the films were examined as a function of substrate temperature. It was found that the emission current from the samples prepared at substrate temperatures higher than 600 °C were considerably improved. According to the results by Raman spectroscopy, growth of graphite crystallites were promoted with high substrate temperatures. Moreover, the surface morphology was abruptly changed at high substrate temperatures over 600 °C. We discuss the field emission characteristics of the amorphous carbon films with regard to the structural features and the surface morphology. 相似文献
11.
W. Deng T. Ohgi H. Nejo D. Fujita 《Applied Physics A: Materials Science & Processing》2001,72(5):595-601
Highly conductive and transparent indium tin oxide (ITO) thin films, each with a thickness of 100 nm, were deposited on glass
and Si(100) by direct current (DC) magnetron sputtering under an argon (Ar) atmosphere using an ITO target composed of 95%
indium oxide and 5% tin oxide for photon-STM use. X-ray diffraction, STM observations, resistivity and transmission measurements
were carried out to study the formation of the films at substrate temperatures between 40 and 400 °C and the effects of thermal
annealing in air between 200 and 400 °C for between1 and 5 h. The film properties were highly dependent on deposition conditions
and on post-deposition film treatment. The films deposited under an Ar atmosphere pressure of ∼1.7×10-3 Torr by DC power sputtering (100 W) at substrate temperatures between 40 and 400 °C exhibited resistivities in the range
3.0–5.7×10-5 Ω m and transmissions in the range 71–79%. After deposition and annealing in air at 300 °C for 1 h, the films showed resistivities
in the range 2.9–4.0×10-5 Ω m and transmissions in the range 78–81%. Resistivity and transmission measurements showed that in order to improve conductive
and transparent properties, 2 h annealing in air at 300 °C was necessary. X-ray diffraction data supported the experimental
measurements of resistivity and transmission on the studies of annealing time. The surface roughness and film uniformity improve
with increasing substrate temperature. STM observations found the ITO films deposited at a substrate temperature of 325 °C,
and up to 400 °C, had domains with crystalline structures. After deposition and annealing in air at 300 °C for 1 h the films
still exhibited similar domains. However, after deposition at substrate temperatures from 40 °C to 300 °C, and annealing in
air at 300 °C for 1 h, the films were shown to be amorphous. More importantly, the STM studies found that the ITO film surfaces
were most likely to break after deposition at a substrate temperature of 325 °C and annealing in air at 300 °C for 2 or 3 h.
Such findings give some inspiration to us in interpreting the effects of annealing on the improvement of conductive and transparent
properties and on the transition of phases. In addition, correlations between the conductive/transparent properties and the
phase transition, the annealing time and the phase transition, and the conductive/transparent properties and the annealing
time have been investigated.
Received: 10 July 2000 / Accepted: 27 October 2000 / Published online: 9 February 2001 相似文献
12.
Radek Zeipl Jarmila Walachová Martin Pavelka Miroslav Jelínek Václav Studnička Tomáš Kocourek 《Applied Physics A: Materials Science & Processing》2008,93(3):663-667
Room temperature conductivity and the Seebeck coefficient of thin layers prepared by laser ablation from Bi2Te3 target were explored. The power factor was calculated for samples prepared at substrate temperature of 360°C with the density
of the laser beam 5 J cm−2 and at substrate temperature of 410°C with the density of the laser beam 2 J cm−2 during the deposition. Oscillations of the conductivity and the power factor with the layer thickness were observed at room
temperature. The oscillations of conductivity were also verified at the temperature of 77 K. The period of oscillations depends
on the preparation conditions. This behavior has been theoretically explained by the quantum size effect in the layers containing
different phases and in addition, it was demonstrated by the X-ray Diffraction measurement.
The behavior of the power factor of the layers is compared to the behavior of the figure of merit of the layers published
earlier. 相似文献
13.
Y. Guhel M. T. Ta J. Bernard B. Boudart J. C. Pesant 《Journal of Raman spectroscopy : JRS》2009,40(4):401-404
We investigated by Raman spectroscopy (RS) the crystalline quality of CeO2 thin films radio frequency magnetron sputtered on n‐type (111) Si substrates from CeO2 target. The deposition temperature was in the range of 200–800 °C. We also realized structural investigations on CeO2 layers after Rapid Thermal Annealing (RTA) performed in the range of 750–1000 °C for 30 s under nitrogen atmosphere. So this study displays that a high‐growth temperature and a high post‐growth‐RTA temperature improves the crystalline structure of the film. In fact, the best crystalline quality, which is close to the CeO2 target taken as a reference, is obtained for a CeO2 layer deposited at 800 °C and post‐annealed at 1000 °C for 30 s. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
14.
Ahti Niilisk Mart Moppel Martti Pärs Ilmo Sildos Taavi Jantson Tea Avarmaa Raivo Jaaniso Jaan Aarik 《Central European Journal of Physics》2006,4(1):105-116
The Raman spectroscopy method was used for structural characterization of TiO2 thin films prepared by atomic layer deposition (ALD) and pulsed laser deposition (PLD) on fused silica and single-crystal
silicon and sapphire substrates. Using ALD, anatase thin films were grown on silica and silicon substrates at temperatures
125–425 °C. At higher deposition temperatures, mixed anatase and rutile phases grew on these substrates. Post-growth annealing
resulted in anatase-to-rutile phase transitions at 750 °C in the case of pure anatase films. The films that contained chlorine
residues and were amorphous in their as-grown stage transformed into anatase phase at 400 °C and retained this phase even
after annealing at 900 °C. On single crystal sapphire substrates, phase-pure rutile films were obtained by ALD at 425 °C and
higher temperatures without additional annealing. Thin films that predominantly contained brookite phase were grown by PLD
on silica substrates using rutile as a starting material. 相似文献
15.
2 and Si lattices at 380 °C, which was defined as zero-mismatch temperature. The implantation was conducted with a metal vapor
vacuum arc (MEVVA) ion implanter at an extraction voltage of 45 kV. Based on a thermal conduction estimation, a temperature
rise of 380 °C required the Ni-ion current density to be 35 μA/cm2. For the Si(111) wafers, the high conducting NiSi2 layers were indeed directly formed after Ni-ion implantation with this specific current density to a normal dose of 2×1017 ions/cm2 and the resistivity was as low as 9 μΩ cm. For the Si(111) wafers pre-covered with a 10-nm Ni overlayer, the resistivity
of the NiSi2 layers obtained under the same conditions decreased down to about 6 μΩ cm. The superior electrical property of the NiSi2 was thought to be related to its formation temperature, i.e. at a zero-mismatch temperature of 380 °C, which resulted in
minimizing the stress and stress-induced defects involved in its formation as well as cooling process.
Received: 27 April 1998 / Accepted: 26 October 1998 相似文献
16.
Hao Wang Y. Wang J. Feng C. Ye B. Y. Wang H. B. Wang Q. Li Y. Jiang A. P. Huang Z. S. Xiao 《Applied Physics A: Materials Science & Processing》2008,93(3):681-684
High-k gate dielectric hafnium dioxide films were grown on Si (100) substrate by pulsed laser deposition at room temperature. The
as-deposited films were amorphous and that were monoclinic and orthorhombic after annealed at 500°C in air and N2 atmosphere, respectively. After annealed, the accumulation capacitance values increase rapidly and the flat-band voltage
shifts from −1.34 V to 0.449 V due to the generation of negative charges via post-annealing. The dielectric constant is in
the range of 8–40 depending on the microstructure. The I–V curve indicates that the films possess of a promising low leakage
current density of 4.2×10−8 A/cm2 at the applied voltage of −1.5 V. 相似文献
17.
To evaluate the exchange current I
o of the oxygen electrode reaction at the O2 strontium-doped lanthanum manganite (LSM)/yttria stabilized zirconia (YSZ) composite/YSZ interface, the variation of the
current I vs overvoltage η is measured at low cathodic and anodic polarizations (−50 to 30 mV). A linear behavior is observed within this potential
domain with a unique slope. Taking into account of the dissociative adsorption of the oxygen molecule on the LSM electrocatalyst
surface and the charge transferred at the triple-phase boundary, the exchange current is evaluated to 2.93 mA in air at 747 °C. 相似文献
18.
N.P. Kobayashi S.-Y. Wang C. Santori R.S. Williams 《Applied Physics A: Materials Science & Processing》2006,85(1):1-6
The epitaxial growth of nanometer-scale structures on non-single crystalline surfaces is proposed and demonstrated. Hydrogenated amorphous silicon was deposited onto an SiO2 surface by plasma-enhanced chemical vapor deposition. Indium phosphide was deposited on the amorphous silicon by low-pressure metalorganic chemical vapor deposition in the presence of colloidal gold particles as catalysts. Under specific growth conditions, the indium phosphide formed nanoneedles connected to a microcrystalline silicon film nucleated within the amorphous silicon during the growth of the nanoneedles. Transmission electron microscopy revealed the presence of two different crystallographic structures: zinc-blende and wurtzite. Micro-photoluminescence measurements at room temperature showed two peaks with substantial blue-shifts with respect to that of bulk zinc-blende indium phosphide. PACS 81.16.Hc; 81.07.Vb; 68.65.La 相似文献
19.
The spectra and photoluminescence kinetics of Er3+ ions embedded in amorphous fluorine- and chlorine-doped silica matrices synthesized by surface-plasma chemical vapor deposition
were investigated at 27–300 K. Luminescence was excited with an Ar+ laser at a wavelength of 514.5 nm and with a diode laser at a wavelength of 975 nm. Narrow and well-expressed components
of Stark sublevels with a small contribution of inhomogeneous broadening intrinsic to Er3+ ions in crystalline rather than amorphous matrices were revealed and identified in photoluminescence spectra. The structure
of Stark sublevels was well-resolved at low temperatures. The presence of the well-resolved Stark structure in spectra was
indicative of stable anion complex formation in Er3+ environment presumably associated with halogen incorporation. This environment was formed at a stage of the low-temperature
plasma-chemical synthesis and was destroyed at glass fusion. 相似文献
20.
J. Teichert L. Bischoff S. Hausmann M. Voelskow H. Hobert 《Applied Physics A: Materials Science & Processing》2000,71(2):175-180
The lattice damage of silicon produced by ion implantation at extremely high current density of 0.8 A/cm2 (2.5᎒18 cm-2 s-1) was investigated. In a focused ion beam system, implantation was carried out with 70 keV Co ions, fluences of 1.2᎒16 cm-2 and 6.7᎒15 cm-2 into Si (111) at room temperature and elevated temperatures between 355 °C and 400 °C. Radiation damage measurements were performed by Rutherford backscattering/channeling spectroscopy and micro-Raman analysis. The radiation damage was studied as a function of pixel dwell-time and implantation temperature. The critical temperature for amorphization increases with current density. Although the fluence of the focused ion implantation was constant, crystalline layers were obtained for short and amorphous layers for long pixel dwell-times. The critical dwell-time of crystalline/amorphous transition increases with implantation temperature. From the results a typical time for defect annealing of 10-5 s at 400 °C and an activation energy of (2.5ǂ.6) eV were deduced. 相似文献