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1.
+ -Si/Ti/WNx/Al multi-layer metallization scheme. The contact resistance has been strongly related to the plasma nitridation of the Ti
surface because the contact resistance of n+-Si/Ti/WNx/Al with contact size of 0.49 μm2 about 100–130 Ω, whereas without the nitridation of the Ti surface the contact resistance rises up to 200–390 Ω. 19F (p,αγ) nuclear resonance analysis and Auger electron spectroscopy reveal that F adatoms on the Ti surface are successfully
removed by the 30 s nitridation and as a result, the low contact resistance can be achieved.
Received: 16 July 1996/Accepted: 5 November 1996 相似文献
2.
Y. Isshiki J. Shi H. Nakai M. Hashimoto 《Applied Physics A: Materials Science & Processing》2000,70(4):395-402
Laser surface alloying (LSA) with silicon was conducted on austenitic stainless steel 304. Silicon slurry composed of silicon
particle of 5 μm in average diameter was made and a uniform layer was supplied on the substrate stainless steel. The surface
was melted with beam-oscillated carbon dioxide laser and then LSA layers of 0.4–1.2 mm in thickness were obtained. When an
impinged energy density was adjusted to be equal to or lower than 100 W mm−2, LSA layers retained rapidly solidified microstructure with dispersed cracks. In these samples, Fe3Si was detected and the concentration of Si in LSA layer was estimated to be 10.5 wt.% maximum. When the energy density was
equal to or greater than 147 W mm−2, cellular grained structure with no crack was formed. No iron silicate was observed and alpha iron content in LSA layers
increased. Si concentration within LSA layers was estimated to be 5 to 9 wt.% on average. Crack-free as-deposited samples
exhibited no distinct corrosion resistance. The segregation of Si was confirmed along the grain boundaries and inside the
grains. The microstructure of these samples changed with solution-annealing and the corrosion resistance was fairly improved
with the time period of solution-annealing.
Received: 2 September 1999 / Accepted: 6 September 1999 / Published online: 1 March 2000 相似文献
3.
Synthesis, integration, and electrical properties of individual single-walled carbon nanotubes 总被引:4,自引:0,他引:4
J. Kong C. Zhou A. Morpurgo H.T. Soh C.F. Quate C. Marcus H. Dai 《Applied Physics A: Materials Science & Processing》1999,69(3):305-308
High-quality single-walled carbon nanotubes (SWNTs) are synthesized by chemical vapor deposition (CVD) of methane on silicon-dioxide
substrates at controlled locations using patterned catalytic islands. With the synthesized nanotube chips, microfabrication
techniques are used to reliably contact individual SWNTs and obtain low contact resistance. The combined chemical synthesis
and microfabrication approaches enable systematic characterization of electron transport properties of a large number of individual
SWNTs. Results of electrical properties of representative semiconducting and metallic SWNTs are presented. The lowest two-terminal
resistance for individual metallic SWNTs (≈5 μm long) is ≈16.5 kΩ measured at 4.2 K.
Received: 17 May 1999 / Accepted: 18 May 1999 / Published online: 14 July 1999 相似文献
4.
This paper deals with the implantation of high-energy (1.0–3.0 MeV) atomic and molecular Al+ ions in Si(100) to a fluence of 5×1014 Al atoms/cm2 at room temperature. The molecular effect, i.e. the increase of the displacement yield compared with the sum of the atomic
yields, and the damage formation as well as defect behaviour after annealing have been investigated. A detailed experimental
study has been made of the evolution of extended secondary defects which form during thermal anneals of Al+ or Al2
+ irradiated silicon. The samples have been examined using combined Rutherford backscattering and channeling experiments together
with transmission electron microscopy observations. The surface structure of the implanted wafers has been measured by atomic
force microscopy. The results for the implantation-induced roughness at the Si surface, resulting from Al+ or Al2
+ irradiation at the same energy/atom, total atomic fluence, flux rate, and irradiation temperature, are presented and discussed.
Received: 19 August 1999 / Accepted: 20 October 1999 / Published online: 23 February 2000 相似文献
5.
F. Machalett K. Edinger J. Melngailis M. Diegel K. Steenbeck E. Steinbeiss 《Applied Physics A: Materials Science & Processing》2000,71(3):331-335
For direct writing of electrically conducting connections and areas into insulating gold oxide thin films a scanning Ar+ laser beam and a 30 keV Ga+ focused ion beam (FIB) have been used. The gold oxide films are prepared by magnetron sputtering under argon/oxygen plasma.
The patterning of larger areas (dimension 10–100 μm) has been carried out with the laser beam by local heating of the selected
area above the decomposition temperature of AuOx (130–150 °C). For smaller dimensions (100 nm to 10 μm) the FIB irradiation could be used. With both complementary methods
a reduction of the sheet resistance by 6–7 orders of magnitude has been achieved in the irradiated regions (e.g. with FIB
irradiation from 1.5×107 Ω/□ to approximately 6 Ω/□). The energy-dispersive X-ray analysis (EDX) show a considerably reduced oxygen content in the
irradiated areas, and scanning electron microscopy (SEM), as well as atomic force microscopy (AFM) investigations, indicate
that the FIB patterning in the low-dose region (1014 Ga+/cm2) is combined with a volume reduction, which is caused by oxygen escape rather than by sputtering.
Received: 30 May 2000 / Accepted: 31 May 2000 / Published online: 13 July 2000 相似文献
6.
Thin-film transistors were made using 50-nm-thick directly deposited nanocrystalline silicon channel layers. The transistors
have a coplanar top gate structure. The nanocrystalline silicon was deposited from discharges in silane, hydrogen and silicon
tetrafluoride. The transistors combine a high electron field effect mobility of ∼10 cm2 V-1s-1 with a low ‘off’ current of ∼10-14 A per μm of channel length and an ‘on’/‘off’ current ratio of ∼108. This result shows that transistors made from directly deposited silicon can combine high mobility with low ‘off’ currents.
Received: 28 May 2001 / Accepted: 30 May 2001 / Published online: 30 August 2001 相似文献
7.
T.J. Rinke R.B. Bergmann J.H. Werner 《Applied Physics A: Materials Science & Processing》1999,68(6):705-707
Thermal crystallization of a double layer porous Si film creates a monocrystalline Si film with a thin separation layer between
the Si film and the reusable starting wafer. The process enables transfer of thin monocrystalline Si films to foreign substrates,
whereby devices may be formed before or after separation of the film. Sub-micrometer thick films are almost compact, while
films with a thickness of several μm contain voids, and are therefore termed “quasi-monocrystalline”. Internal voids strongly
enhance optical absorption by light scattering. The hole mobility is 78 cm2 V-1 s-1 at a p-type starting wafer resistivity of 0.05 Ω cm.
Received: 24 March 1999 / Accepted: 29 March 1999 / Published online: 5 May 1999 相似文献
8.
C. Berger Y. Yi Z.L. Wang W.A. de Heer 《Applied Physics A: Materials Science & Processing》2002,75(3):363-365
Following the experiments of Frank et al. [1], which demonstrated quantum transport in multiwalled carbon nanotubes, there
have been several experiments that appear to contradict the main conclusion of that paper, which is that the transport of
a MWNT at room temperature is ballistic. Here we demonstrate that the intrinsic resistance of clean-arc-produced carbon nanotubes
is at most 200 Ω/ μm, which implies that the momentum mean free path is greater than 30 μm, which in turn is much larger than
the tube length. This implies that these tubes are ballistic, according to the standard definition of ballistic transport.
We also show that the contact resistance with mercury is quite large: a nanotube in contact with Hg over 100 nm of its length
still represents a 3000 Ω resistance.
Received: 14 September 2001 / Accepted: 3 December 2001 / Published online: 4 March 2002 相似文献
9.
Silicon diodes with a p
+-n junction made in a 48-μm-thick phosphorus-doped silicon epilayer (resistivity ρ = 30 Ω cm) grown on antimony-doped Si(111)
wafers (ρ = 0.01 Ω cm) are studied. The diodes are irradiated by high-energy (3.5 MeV) electrons with fluences from 5 × 1015 to 2 × 1016 cm−2. It is shown that the conventional equivalent circuit of the diode that consists of a parallel RC network and a series-connected resistor inadequately describes the dependence of the dielectric loss tanδ on variable current
frequency f in the range 1 × 102–3 × 107 Hz. Another equivalent circuit is suggested that includes not only the capacitance and resistance of the n-base (the latter increases because radiation-induced defects are compensated for by shallow donors) but also the f dependence of the capacitance of the space-charge region, which is due to retarded charge exchange between deep-level radiation-induced
defects. 相似文献
10.
A.A. Andreev U. Teubner I.V. Kurnin E. Förster 《Applied physics. B, Lasers and optics》2000,70(4):505-515
Soft-X-radiation in the “water-window” region (23.3–43.6 ?) mainly from carbon laser plasmas generated by subpicosecond (700 fs)
0.248-μm laser pulses is studied as a function of angle of incidence and intensity (up to 1018 W/cm2) for p-polarized laser light. Furthermore, comparison is made between plasmas generated from massive and foil targets. Numerical
calculations are performed using a hydrocode coupled to X-ray line and continuum emission calculations including radiation
transport. The optimized conditions to achieve maximum water-window X-ray emissivity and, in particular, carbon Lyman-α line
emission are investigated. In addition, analytical scalings are presented. These theoretical results are essentially confirmed
by previous experiments. It is found that at optimized conditions, picosecond or subpicosecond laser plasma X-ray sources
with a power of the order of 1–10 GW in a spectral window of 1 ? could be developed.
Received: 6 August 1998 / Final version: 6 August 1999 / Published online: 30 November 1999 相似文献
11.
M. Quinten 《Applied physics. B, Lasers and optics》2000,70(4):579-586
Extended Mie-theory is used to investigate scattering and extinction of evanescent waves by aggregates of clusters. In an
application to apertureless near-field optical microscopy involving total internal reflection at the surface substrate–air,
the variation of the scattered power is calculated when a silicon particle is scanned across single clusters or aggregates
of clusters in the evanescent field. Metallic, dielectric, and semiconducting particles are taken into consideration, and
the dependence on sizes, materials, and the wavelength is discussed.
Received: 27 August 1999 / Revised version: 8 November 1999 / Published online: 1 March 2000 相似文献
12.
M. Dorikens C. Dauwe L. Dorikens-Vanpraet 《Applied Physics A: Materials Science & Processing》1974,4(3):271-272
Positron lifetime measurements were carried out in four different samples of silicon, namelyn-type (P-doped) 75 Ωcm,n-type (Sb-doped) 0.018 Ωcm,p-type (B-doped) 60 Ωcm andp-type (B-doped) 0.02 Ωcm. The measurements were made at room temperature and at 77K. A positron lifetime of τ1=(230±2) psec was found for all samples, independant of dopant or temperature.
Paper A 17 presented at 3 rd Internat'l Conf. Positron Annihilation. Otaniemi, Finland (August 1973). 相似文献
13.
The crystalline silicon thin-film solar cell combines, in principle, the advantages of crystalline silicon wafer-based solar
cells and of thin-film solar cell technologies. Its efficiency potential is the highest of all thin-film cells. In the “high-temperature
approach” thin silicon layers are deposited on substrates that withstand processing temperatures higher than 1000 °C. The
basic features of the high-temperature crystalline silicon thin-film cell technology are described and some important results
are discussed.
Received: 1 March 1999 / Accepted: 28 March 1999 / Published online: 24 June 1999 相似文献
14.
Z. Guo Y. Li Z. Ge J. Yan D. Zhu J. Si P. Ye 《Applied physics. B, Lasers and optics》2000,71(4):545-548
The Langmuir and Langmuir–Blodgett (LB) films of a novel crowned [60]fullero-pyrrolidine (CFP) were produced in different
conditions. Macroscopic second-harmonic generation of the LB film was investigated by means of AM1 Hamiltonian as well as
experiments. The monolayer LB film displayed a periodic fringe pattern. A linear dependence of second-harmonic intensity on
the number of layers was observed. The second-order molecular susceptibility χ(2) and hyperpolarizability β were evaluated to be 3.2×10−8 and 8.3×10−29 esu.
Received: 21 October 1999 / Revised version: 30 March 2000 / Published online: 2 August 2000 相似文献
15.
S. Civiš A.N. Imenkov A.P. Danilova N.M. Kolchanova V.V. Sherstnev Y.P. Yakovlev A.D. Walters 《Applied physics. B, Lasers and optics》2000,71(4):481-485
A new type of multimode semiconductor laser, based on InAsSb/InAsSbP heterostructures, is described. This continuous laser
working in a broad range of temperatures (30–100 K) was tested using a closed-cycle He-cryostat and its quality was demonstrated
using the laser spectroscopy of gases absorbing in the 2800 cm-1 region. Two different laser modes were used to increase the spectral range. The spectral characteristics and tunability of
the laser were explored as a function of heat-sink temperature and drive current with the aim of developing its use for high–resolution
spectroscopy. The laser has potential applications in the field of chemistry, atmospheric research and the study of the kinetics
of reactive species.
Received: 18 October 1999 / Revised version: 10 May 2000 / Published online: 16 August 2000 相似文献
16.
We have measured the absorption of the 19.47-nm neon like bromine (J=2–1) X-ray laser line in low-pressure helium. The experiment
was motivated by the coincidence of this line with the low-absorption wing of an autoionizing transition in helium. We observe
that, with 1 mbar of helium, the continuum background and another bromine X-ray laser line at 19.82 nm are strongly reduced,
enhancing the relative strength of the 19.47-nm laser line. Increasing the helium pressure to 1.5 mbar makes the continuum
virtually disappear, resulting in an almost monochromatic emission of the X-ray laser line. An estimate of the absorption
cross section for the 19.47-nm line is given as ≈3.9×10-19 cm2 and for the nearby continuum as 0.9–1.3×10-18 cm2.
Received: 8 March 1999 / Revised version: 26 April 1999 / Published online: 11 August 1999 相似文献
17.
Z. Guo Y. Li J. Yan F. Bai F. Li D. Zhu J. Si P. Ye 《Applied physics. B, Lasers and optics》2000,70(2):257-260
The photophysical properties of the first crown ether-bearing [60]fulleropyrrolidine (CFP) have been studied. The absorption
and fluorescence spectra are hypsochromically shifted by metal ions complexation via intramolecular electron transfer which
is confirmed by AMI computation. The third-order optical nonlinearity of CFP is measured by time-resolved degenerate four-wave-mixing
experiment. The third-order optical susceptibility χ(3) of CFP is 8.97×10−14 esu. The nonlinear optical temporal response is second-order exponential, the fast process is determined as 120 ps.
Received: 24 March 1999 / Revised version: 11 May 1999 / Published online: 25 August 1999 相似文献
18.
B. Shen Y.G. Zhou Z.Z. Chen P. Chen R. Zhang Y. Shi Y.D. Zheng W. Tong W. Park 《Applied Physics A: Materials Science & Processing》1999,68(5):593-596
Epitaxial growth of high-quality hexagonal GaN films on sapphire substrates using light-radiation heating metal-organic chemical
vapor deposition (LRH-MOCVD) is first reported. The deposition temperature is 950 °C, about 100 °C lower than that in normal
rf-heating MOCVD growth. The FWHM of GaN (0002) peak of the X-ray diffraction rocking curve is 8.7 arc min. Photoluminescence
spectrum of GaN film shows that there is a very strong band-edge emission and no “yellow-band” luminescence. Hall measurement
indicates that the n-type background carrier concentration of GaN film is 1.7×1018 cm-3 and the Hall mobility of it is 121.5 cm2/V s. It is suggested that the radiation of light in GaN growth enhances the dissociation of ammonia and decreases the disadvantages
of the parasite reaction between trimethylgallium and ammonia.
Received: 20 August 1998 / Accepted: 30 October 1998 / Published online: 10 March 1999 相似文献
19.
A. Klett A. Malavé R. Freudenstein M.F. Plass W. Kulisch 《Applied Physics A: Materials Science & Processing》1999,69(6):653-656
Cubic boron nitride thin films have been ion-beam-assisted deposited on silicon cantilever structures and subsequently back-etched
in order to study the stress evolution and finally the growth mechanisms. After each sputtering step, the film stress, the
remaining thickness, and the IR data were examined. In this way, the layered sequence of cBN on top of a hBN base layer, influencing
the development of the intrinsic film stress, could be studied in detail. The observed stress distribution can be divided
into three regions. First, a non-cubic base layer with a constant stress value is formed, followed by a linear increase in
the stress after cBN nucleation as a result of the coalescence of cBN nanocrystals. Finally, the stress reaches a second plateau
characteristic of the cBN top layer. In addition, the layered sequence was verified by the evolution of the FTIR spectra.
Furthermore, the fraction of the sp2-bonded material of the cBN top layer was determined from the IR data. For various deposition conditions, a linear relationship
between the stress of the nanocrystalline cBN top layer and the amount of sp3-bonded material was observed. From this, it can be concluded that stress relaxation occurs at the sp2-bonded grain boundary material. No evidence for stress relaxation after cBN nucleation was found.
Received: 27 August 1999 / Accepted: 31 August 1999 / Published online: 3 November 1999 相似文献
20.
C.J. da Silva M.T. de Araujo E.A. Gouveia A.S. Gouveia-Neto 《Applied physics. B, Lasers and optics》2000,70(2):185-188
The temperature effect upon infrared-to-visible frequency upconversion fluorescence emission in Yb3+-sensitized Er3+-doped germanosilicate optical fibers excited with cw radiation at 1.064 μm is investigated. The experimental results revealed
an eightfold enhancement in the visible upconversion emission intensity as the fiber temperature was increased from 17 °C
to 180 °C. The fluorescence emission enhancement is attributed to the temperature-dependent multiphonon-assisted anti-Stokes
excitation process of the ytterbium sensitizer. A theoretical approach that takes into account a sensitizer absorption cross-section,
which depends on the phonon occupation number, has proven to agree very well with the experimental data
Received: 6 April 1999 / Revised version: 27 August 1999 / Published online: 27 January 2000 相似文献