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1.
The recent achievements of high-efficiency
Cu(In,Ga)Se2 heterojunction solar cells are reviewed with a special focus on the understanding of the electronic transport properties
of the devices. We discuss the basic limitations of the device performance, the present understanding of electronic device
analysis, as well as the role of intrinsic defects and of the interfaces for the performance of the solar cells.
Received: 12 March 1999 / Accepted: 28 March 1999 / Published online: 24 June 1999 相似文献
2.
Solid-state diffusion of impurities into crystals and quasicrystals is essential for many physical processes concerned with
the growth of novel semiconductor materials and the fabrication of electronic/energy devices with commercial viability. Here
relevant considerations about diffusion in these systems are presented and discussed. 相似文献
3.
R. Verucchi L. Aversa G. Ciullo A. Podestà P. Milani S. Iannotta 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(4):509-514
The development of electronic devices based on Silicon Carbide (SiC) has been strongly limited by the difficulties in growing
high quality crystalline bulk materials and films. We have recently elaborated a new technique for the synthesis of SiC on
clean Si substrates by means of supersonic beams of C60: the electronic and structural properties of the film can be controlled by monitoring the beam parameters, i.e. flux and particles energy and aggregation state. SiC films were grown in Ultra High Vacuum on Si(111)-7×7, at substrates temperatures of 800
°
C, using two different supersonic beams of C60: He and H2 have been used as seeding gases, leading to particles energy of 5 eV and 20 eV, respectively. Surface characterisation was
done in situ by Auger and X-Ray photoelectron spectroscopy, as well as by low energy electron diffraction and ex situ by atomic force microscopy technique. SiC films exhibited good structural and electronic properties, with presence of defects
different from the typical triangular voids.
Received 20 November 2001 相似文献
4.
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
5.
L. Schlapbach A. Züttel P. Gröning O. Gröning P. Aebi 《Applied Physics A: Materials Science & Processing》2001,72(2):245-253
We start by recalling some of the properties of hydrogen and present a summary of the phenomena caused by the reversible hydrogen
sorption by metals and various forms of condensed carbon, at the surface and into the bulk, using molecular hydrogen gas,
hydrogen plasma and electrochemically sorbed hydrogen. We then describe the use of hydrogen to modify the surface and bulk
properties of various materials with a focus on applications and devices: electronic and optic phase transitions of thin films
and related energy devices, surface polishing and cleaning, decrepitation and amorphization of intermetallics, growth of carbon
nanostructures and electron emission from diamond-like and graphitic carbon, longrange perturbation of the electron distribution
of graphitic structures by hydrogen defects, and the consequences for potential nanoelectronics.
Received: 8 November 2000 / Accepted: 20 November 2000 / Published online: 9 February 2001 相似文献
6.
W. Swiech G.H. Fecher M. Huth O. Schmidt N.-F. Cheng C.-K. Lin C.-Y. Tung Y. Hwu 《Applied Physics A: Materials Science & Processing》1998,67(4):447-454
2 Al3 and YBa2Cu3O7/PrBa2Cu3O7. To investigate devices built from these complex materials we applied element-sensitive photoemission electron microscopy
(PEEM). Information about the chemical composition of the imaged sample can be obtained by PEEM via tuning the photon energy
to X-ray absorption edges. To apply spectromicroscopy we acquired microscopic images using photon energies near and at the
edges. Such images give the lateral distribution of a specific element. Microspectroscopy is performed by recording the intensity
of the true secondary electrons in selected spots during a sweep of the photon energy. The main aim of our work was to observe
oxygen-related defects and changes in the composition affecting the physical properties of the materials. Therefore, we applied
both methods to micro-patterned devices using soft-X-ray synchrotron radiation and found that small local defects and chemical
differences can be easily detected. Such defects and chemical differences are quite critical to the physical properties of
the devices, since they simulate spurious effects thus influencing the reliability of the devices.
Received: 13 March 1998/Accepted: 22 April 1998 相似文献
7.
M.S. Zhang P. Zhang Z. Yin J. Liu 《Applied Physics A: Materials Science & Processing》1999,69(4):389-395
Barium sodium niobate (BSN) optical waveguide films were grown on potassium titanyl phosphate (KTP) substrate by pulsed laser
deposition (PLD). X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray pole spectroscopy, and X-ray photoelectron
spectroscopy (XPS) showed that the as-grown BSN films are epitaxially smooth, fine-particled and show small constituent deviation.
Both m lines of the waveguided TE and TM modes were recorded. Lattice match between the BSN(110) and both the KTP(001) and KTP(100)
planes is examined with mismatch less than 3%. Effective refractive indices as a function of incident wavelength and order
of the waveguided modes are studied. A phase matching relationship of k
(1)−2k
(0)=0 is established between the first-order and fundamental modes in the BSN/KTP waveguided system. Effective thicknesses for
TE and TM modes were obtained to be equal to 0.76 and 0.72 μm, respectively, larger than the thickness of the as-grown BSN
film of 0.60 μm. A constituent ratio of Ba:Na:Nb in the BSN film measured was equal to 2:0.82:5.14, slightly deviating from
the stoichiometric ratio of 2:1:5, which is attributed to higher relative asymptotic velocity for Nb species and higher evaporation
pressure for Na species. Finally, the main factors affecting quality of the as-grown BSN films are also discussed.
Received: 26 March 1999 / Accepted: 30 March 1999 / Published online: 19 August 1999 相似文献
8.
A. Brockhinke W. Kreutner U. Rahmann K. Kohse-Höinghaus T.B. Settersten M.A. Linne 《Applied physics. B, Lasers and optics》1999,69(5-6):477-485
Laser-induced fluorescence of OH (A 2Σ+, v’=1) was measured in hydrogen/oxygen and hydrogen/air/nitrogen flames using laser pulses of 80 psec duration. A 2D signal
acquisition scheme simultaneously employed wavelength, temporal, and polarization resolution. The signals emitted in different
rotational branches exhibit polarization-dependent intensities, depending on the rotational branch of the absorption line
used. It is possible to select experimental conditions such that rotational and vibrational relaxation as well as electronic
quenching can be monitored simultaneously. Advantages and limitations of the experimental approach are discussed. Numerical
simulations are presented of the LIF spectra affected by energy transfer.
Received: 29 March 1999 / Revised version: 14 June 1999 / Published online: 27 October 1999 相似文献
9.
N. Manikanthababu N. Arun M. Dhanunjaya V. Saikiran S.V.S. Nageswara Rao 《辐射效应与固体损伤》2015,170(3):207-217
The current trend in miniaturization of metal oxide semiconductor devices needs high-k dielectric materials as gate dielectrics. Among all the high-k dielectric materials, HfO2 enticed the most attention, and it has already been introduced as a new gate dielectric by the semiconductor industry. High dielectric constant (HfO2) films (10?nm) were deposited on Si substrates using the e-beam evaporation technique. These samples were characterized by various structural and electrical characterization techniques. Rutherford backscattering spectrometry, X-ray reflectivity, and energy-dispersive X-ray analysis measurements were performed to determine the thickness and stoichiometry of these films. The results obtained from various measurements are found to be consistent with each other. These samples were further characterized by I–V (leakage current) and C–V measurements after depositing suitable metal contacts. A significant decrease in the leakage current and the corresponding increase in device capacitance are observed when these samples were annealed in oxygen atmosphere. Furthermore, we have studied the influence of gamma irradiation on the electrical properties of these films as a function of the irradiation dose. The observed increase in the leakage current accompanied by changes in various other parameters, such as accumulation capacitance, inversion capacitance, flat band voltage, mid-gap voltage, etc., indicates the presence of various types of defects in irradiated samples. 相似文献
10.
N. Esser 《Applied Physics A: Materials Science & Processing》1999,69(5):507-518
Only recently Raman spectroscopy (RS) has advanced into the study of surface phonons from clean and adsorbate-covered semiconductor
surfaces. RS allows the determination of eigenfrequencies as well as symmetry selection rules of surface phonons, by k-conservation limited to the Brillouin zone-center, and offers a significantly higher spectral resolution than standard surface
science techniques such as high-resolution electron energy loss spectroscopy. Moreover, surface electronic states become accessible
via electron–phonon coupling. In this article the fundamentals of Raman scattering from surface phonons are discussed and
its potential illustrated by considering two examples, namely Sb-monolayer-terminated and clean InP(110) surfaces. Both are
very well understood with respect to their atomic and electronic structure and thus may be regarded as model systems for heteroterminated
and clean semiconductor surfaces. In both cases, localized surface phonons as well as surface resonances are detected by Raman
spectroscopy. The experimental results are compared with surface modes predicted by theoretical calculations. On InP(110),
due to the high spectral resolution of Raman spectroscopy, several surface modes predicted by theory can be experimentally
verified. Surface electronic transitions are detected by changing the energy of the exciting laser light indicating resonances
in the RS cross section.
Received: 7 April 1999 / Accepted: 25 June 1999 / Published online: 16 September 1999 相似文献
11.
Electron ratchet effect in semiconductor devices and artificial materials with broken centrosymmetry
A.M. Song 《Applied Physics A: Materials Science & Processing》2002,75(2):229-235
Studies on nonlinear electron transport in nanometer-sized semiconductor devices with broken centrosymmetry are reviewed.
In these devices, an applied alternating (rocking) electric field induces a net flow of electrons in the direction perpendicular
to that of the applied field. Such an electron ratchet effect has been observed in a number of differently designed devices,
fabricated from two types of semiconductor material systems. The functionality is interpreted with an extended Büttiker–Landauer
formula. We show that the devices operate at both cryogenic and room temperatures and at frequencies up to at least 50 GHz.
Based on a similar microscopic mechanism, we have also constructed, to the best of our knowledge, the first artificial electronic
nanomaterial that operates at room temperature. The promising possibilities for practical applications, such as rectification,
microwave detection, second-harmonic generation, etc., are also discussed.
Received: 16 January 2002 / Accepted: 11 February 2002 / Published online: 22 April 2002 相似文献
12.
L. M. Walpita 《Fiber and Integrated Optics》1990,9(1):27-36
During the last two decades, lithium niobate has been extensively studied for applications in integrated optical circuits. However, it is difficult to integrate lithium niobate optical devices with semiconductor electronic devices because the materials are incompatible. In recent years, semiconductor materials have been emerging as the main contenders in applications; these materials have the advantage of allowing both optical and electronic devices to be integrated. Further, the semiconductor technology has advanced rapidly, allowing us to engineer device parameters very precisely. In semiconductor optoelectronic devices, that is, bulk and quantum well structures, electroabsorption has mainly been used for amplitude modulation of light. The electrorefraction effect is the most useful for devices employing phase-modulation techniques, but this effect cannot be effectively utilized in semiconductors since the strongest electrorefraction effect is near the absorption edge of the material. Recently, organic materials have been shown to have electro-optic coefficients equal to or larger than that of lithium niobate. There are major advantages of organic materials: (1) the organics can be deposited on semiconductor substrates, and therefore both electronic and optical circuits can be integrated; (2) in organic materials the electrorefraction can be effectively utilized to obtain both amplitude and phase modulation; (3) the organic material composition can be adjusted to satisfy some device requirements. In this paper, a comparison of these material systems are made in terms of device applications. 相似文献
13.
Cross-sectional scanning tunneling microscopy is used to study defects on the surface of semiconductor laser devices. Step defects across the active region caused by the cleave process are identified. Curved blocking layers used in buried heterostructure lasers are shown to induce strain in the layers above them. Devices are also studied whilst powered to look at how the devices change during operation, with a numerical model that confirms the observed behavior. Whilst powered, low-doped blocking layers adjacent to the active region are found to change in real time, with dopant diffusion and the formation of surface states. A tunneling model which allows the inclusion of surface states and tip-induced band bending is applied to analyze the effects on the tunneling current, confirming that the doping concentration is reducing and defect surface states are being formed. 相似文献
14.
P.V. Grujić 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(4):441-450
We calculate rovibronic intrashell spectra of the triply highly excited atomic hydrogen dianion, helium anion and lithium
atom, within a simple semiclassical model. Zero-order electronic energy levels and half-lives are calculated for a number
of principal quantum numbers and approximate thresholds for the appearance of vibronic modes are estimated. Since no quantum-mechanical
and experimental data are available for the highly excited levels (N > 5), where the semiclassical models apply, no comparison with other results are possible at present. The problem of comparing
semiclassical and quantum-mechanical calculations for moderately large quantum numbers, which seem attainable by the present
day experimental technique, has been discussed.
Received: 16 September 1998 / Received in final form: 16 March 1999 相似文献
15.
Mingshan Xue Zhonghao Jiang Wen Li Guangli BiJunfei Ou Fajun WangChangquan Li 《Applied Surface Science》2012,258(8):3373-3377
Organic semiconductor materials are becoming a promising subject of not only scientific interest but also potential applications in the field of new energy resources. In this study, the copper phthalocyanine (CuPc) films as an excellent organic semiconductor were self-assembly grown on indium tin oxide glass by electrodeposition, the structural and electronic properties were investigated using various techniques. The results demonstrated that ordered α-form crystalline CuPc films were obtained. The decrease of electron work function of CuPc films with the increase of film thickness was found, which was obviously dependent on the surface morphology. The understanding of these behaviors of CuPc films will be significant for designing related photoelectric devices. 相似文献
16.
Shaun D. Gittard John R. Perfect Wei Wei Roger J. Narayan 《Applied Surface Science》2009,255(11):5806-5811
The electronic and chemical properties of semiconductor materials may be useful in preventing growth of microorganisms. In this article, in vitro methods for assessing microbial growth on semiconductor materials will be presented. The structural and biological properties of silicon wafers coated with zinc oxide thin films were evaluated using atomic force microscopy, X-ray photoelectron spectroscopy, and MTT viability assay. The antimicrobial properties of zinc oxide thin films were established using disk diffusion and CDC Biofilm Reactor studies. Our results suggest that zinc oxide and other semiconductor materials may play a leading role in providing antimicrobial functionality to the next-generation medical devices. 相似文献
17.
T. Kamiya A. Suemasu T. Watanabe T. Sameshima I. Shimizu 《Applied Physics A: Materials Science & Processing》2001,73(2):151-159
The carrier transport property of polycrystalline silicon (poly-Si:H:F) thin films was studied in relation to film microstructure,
impurity, in situ or post-annealing treatments to obtain better carrier transport properties. Poly-Si:H:F films were prepared
from SiF4 and H2 gas mixtures at temperatures <300 °C. Dark conductivity of the films prepared at high SiF4/H2 gas flow ratio (e.g., 60/3 sccm) exhibits a high value for intrinsic silicon and its Fermi level is located near the conduction
band edge. The carrier incorporation is suppressed well, either by in situ hydrogen plasma treatment or by post-annealing
with high-pressure hot-H2O vapor. It is confirmed that weak-bonded hydrogen atoms are removed by the hot-H2O vapor annealing. In addition, evident correlation between impurity concentrations and dark conductivity is not found for
these films. It is thought that the carrier incorporation in the films prepared at high SiF4/H2 gas flow ratios is related to grain-boundary defects such as weak-bonded hydrogen. By applying hot-H2O vapor annealing at 310 °C to a 1-μm-thick p-doped (400)-oriented poly-Si:H:F film, Hall mobility was improved from 10 cm2/Vs to 17 cm2/Vs.
Received: 7 August 2000 / Accepted: 2 March 2001 / Published online: 20 June 2001 相似文献
18.
H.A.M. de Gronckel H. Kohlstedt C. Daniels 《Applied Physics A: Materials Science & Processing》2000,70(4):435-441
Aluminum films with thicknesses ranging from 1 nm to 12 nm have been sputtered on 20 nm thick Co layers. The properties of
the Co/Al bilayers were studied by X-ray photoemission spectroscopy (XPS) and spin-echo nuclear magnetic resonance (NMR).
Both methods show independently that a 1 nm Al film covers the Co surface completely. XPS and NMR also showed that layers
thicker than 1 nm Al are not oxidized completely in ambient air. Similarities to and deviations from niobium with Al overlayers
(Nb/Al) are described. Prerequisites for the fabrication of tunneling magnetoresistance devices based on Co or NiFe ferromagnets
and an aluminum oxide barrier are discussed.
Received: 7 July 1999 / Accepted: 11 November 1999 / Published online: 8 March 2000 相似文献
19.
M. Schindler S. K. Kim C. S. Hwang C. Schindler A. Offenhusser S. Ingebrandt 《固体物理学:研究快报》2008,2(1):4-6
Sensors, which are designed and fabricated in complementary metal oxide semiconductor (CMOS) technology, have become increasingly important in the field of bioelectronics. The standardized industry processes enable a fast, cheap, and reliable fabrication of biosensor devices with integrated addressing and processing units. However, the interfacing of such chips with a liquid environment has been a challenge in recent years. Especially for interfacing living cells with CMOS biosensors different elaborate post‐processes have been proposed. In this article we describe a novel and single step passivation of a CMOS biosensor using a bio‐compatible high‐permittivity thin film, which can be directly applied to the top aluminium layer of a CMOS process. The aluminium oxide and hafnium oxide multi‐layer thin films were prepared using atomic layer deposition at low process temperatures. Electrical I –V and capacitance measurements as well as electrochemical leakage current measurements were performed on films grown on aluminium bottom electrodes. The films showed a very low leakage current and were stable up to 6 V at a thickness of just 50 nm. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
20.
Electrically Tunable Wafer-Sized Three-Dimensional Topological Insulator Thin Films Grown by Magnetron Sputtering
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《中国物理快报》2020,(5)
Three-dimensional(3 D) topological insulators(TIs) are candidate materials for various electronic and spintronic devices due to their strong spin-orbit coupling and unique surface electronic structure.Rapid,low-cost preparation of large-area TI thin films compatible with conventional semiconductor technology is the key to the practical applications of TIs.Here we show that wafer-sized Bi_2 Te_3 family TI and magnetic TI films with decent quality and well-controlled composition and properties can be prepared on amorphous SiO_2/Si substrates by magnetron cosputtering.The SiO_2/Si substrates enable us to electrically tune(Bi_(1-x)Sb_x)_2 Te_3 and Cr-doped(Bi_(1-x)Sb_x)_2 Te_3 TI films between p-type and n-type behavior and thus study the phenomena associated with topological surface states,such as the quantum anomalous Hall effect(QAHE).This work significantly facilitates the fabrication of TI-based devices for electronic and spintronic applications. 相似文献