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24 Nov 1997

Volume 71, Issue 21, pp. 3033-3176

Page 2 of 2 Pages Previous Page | Jump to Page

Spatially selective disordering of InGaAs/GaAs quantum wells using an AlAs native oxide and thermal annealing technique

Chao-Kun Lin, Xingang Zhang, P. Daniel Dapkus, and Daniel H. Rich

Appl. Phys. Lett. 71, 3108 (1997); http://dx.doi.org/10.1063/1.120261 (3 pages) | Cited 8 times

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An InGaAs/GaAs quantum well (QW) disordering technique using AlAs native oxide and thermal annealing is presented. Unlike dielectric cap disordering, the AlAs native oxide can be placed close to quantum wells allowing for a spatially selective disordering deep within multilayer structures. The QW energy shifts and spatial control of the disordering were studied with photoluminescence and cathodoluminescence. The QW energy shift of thermally disordered regions containing buried oxide layer is ∼ 45 meV greater than that of regions not containing buried oxide layers. The disordering transition width is estimated to be ∼ 1 μm. © 1997 American Institute of Physics.
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81.05.Ea III-V semiconductors
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
78.55.Cr III-V semiconductors
81.65.Mq Oxidation
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.61.Ey III-V semiconductors
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
78.66.Fd III-V semiconductors
78.60.Hk Cathodoluminescence, ionoluminescence
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Effect of buffer layer and substrate surface polarity on the growth by molecular beam epitaxy of GaN on ZnO

F. Hamdani, A. E. Botchkarev, H. Tang, W. Kim, and H. Morkoç

Appl. Phys. Lett. 71, 3111 (1997); http://dx.doi.org/10.1063/1.120262 (3 pages) | Cited 24 times

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We present results on the effect of substrate surface polarity, oxygen and zinc faces, on the quality of GaN epitaxial layers grown on ZnO(0001) substrates by reactive ammonia molecular beam epitaxy. The possible effects dealing with the disparity in surface preparation of the two faces have been eliminated. Photoluminescence and reflectivity measurements demonstrate that the oxygen face leads to higher quality GaN on ZnO compared to the zinc face. We also present optical data obtained by using different low-temperature AlN, GaN, and InxGa1−xN buffer layers. The best result has been obtained with lattice-matched In0.20Ga0.80N buffer layer. © 1997 American Institute of Physics.
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81.05.Ea III-V semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

The effect of H2 on morphology evolution during GaN metalorganic chemical vapor deposition

J. Han, T.-B. Ng, R. M. Biefeld, M. H. Crawford, and D. M. Follstaedt

Appl. Phys. Lett. 71, 3114 (1997); http://dx.doi.org/10.1063/1.120263 (3 pages) | Cited 71 times

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In situ optical reflectance transients reveal that the morphology evolution of the initial low-temperature buffer layer strongly influences the structural and electrical quality of the high-temperature GaN films. Moreover, the morphology evolution of that buffer layer, specifically evolution of the spatial and orientational distributions of the nuclei, is strongly affected by H2. The growth conditions for which surface smoothness is maintained throughout the two-step growth do not necessarily produce the best quality final GaN films; instead, there may be an optimal roughness and incubation period en route to the best quality final films.
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81.05.Ea III-V semiconductors
68.55.-a Thin film structure and morphology
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.61.Ey III-V semiconductors
68.35.B- Structure of clean surfaces (and surface reconstruction)
78.66.Fd III-V semiconductors
78.20.-e Optical properties of bulk materials and thin films

Optically induced current bistability in coupled quantum wells

Anand V. Ramamurthi, Vivek Srinivas, and G. M. Hegde

Appl. Phys. Lett. 71, 3117 (1997); http://dx.doi.org/10.1063/1.120264 (3 pages)

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We report the observation of bistability in the photocurrent and photoluminescence spectra of GaAs quantum well heterostructures. The excitation energy is nonresonant and above the band-gap energy of the barrier. A self-consistent calculation taking into account the rate equations governing the charge distribution in the wells is shown to result in the observed bistability which leads to a new class of optically bistable devices. © 1997 American Institute of Physics.
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73.61.Ey III-V semiconductors
78.66.Fd III-V semiconductors
72.40.+w Photoconduction and photovoltaic effects
42.65.Pc Optical bistability, multistability, and switching, including local field effects
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.55.Cr III-V semiconductors

Photoluminescence determination of the Be binding energy in direct-gap AlGaAs

N. Galbiati, C. Gatti, E. Grilli, M. Guzzi, L. Pavesi, and M. Henini

Appl. Phys. Lett. 71, 3120 (1997); http://dx.doi.org/10.1063/1.120265 (3 pages)

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The Be binding energy [EABe(x)] as a function of the Al content in AlxGa1−xAs has been determined by photoluminescence measurements of direct-gap Be-doped AlxGa1−xAs (0 ⩽ x ⩽ 0.315) samples grown by molecular beam epitaxy. It has been found EABe(x) = 27.5+98x2 (meV) which is systematically lower than other literature values. © 1997 American Institute of Physics.
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78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors
73.20.Hb Impurity and defect levels; energy states of adsorbed species
71.55.Eq III-V semiconductors

Localized electron trapping and trap distributions in SiO2 gate oxides

R. Ludeke and H. J. Wen

Appl. Phys. Lett. 71, 3123 (1997); http://dx.doi.org/10.1063/1.120266 (3 pages) | Cited 7 times

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Localized trap filling and trap creation in SiO2 were investigated by injecting electrons into metal-oxide-semiconductor structures with a scanning tunneling microscope. The resulting charging causes changes in the oxide potential that were studied as a function of an applied oxide field. The charge densities and charge distributions were obtained by modeling the field dependence of the potential arising from multiple sets of sheet charges in the oxide. © 1997 American Institute of Physics.
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73.61.Ng Insulators
73.20.Fz Weak or Anderson localization
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)

A physically based predictive model of Si/SiO2 interface trap generation resulting from the presence of holes in the SiO2

P. M. Lenahan and J. F. Conley

Appl. Phys. Lett. 71, 3126 (1997); http://dx.doi.org/10.1063/1.120284 (3 pages) | Cited 10 times

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A physically based model is developed which explains apparently unrelated aspects of the Si/SiO2 interface trap generation process; the predictions of the model are in at least semiquantitative agreement with observations previously reported in the literature. The model involves interactions between molecular hydrogen and trivalent silicon dangling bond defects in the oxide (E′ centers) and at the Si/SiO2 interface (Pb centers). Our model is primarily directed at interface trap generation caused by ionizing radiation and by hot hole injection phenomena observed in short channel transistors. © 1997 American Institute of Physics.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.20.Hb Impurity and defect levels; energy states of adsorbed species

Influence of germanium content on the photoluminescence of erbium- and oxygen-doped SiGe grown by molecular beam epitaxy

E. Neufeld, A. Sticht, K. Brunner, G. Abstreiter, H. Holzbrecher, H. Bay, and Ch. Buchal

Appl. Phys. Lett. 71, 3129 (1997); http://dx.doi.org/10.1063/1.120267 (3 pages) | Cited 8 times

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The photoluminescence at 1.54 μm of erbium- and oxygen-doped Si/Si1−xGex samples grown completely by molecular beam epitaxy has been investigated for germanium concentrations ranging from x = 0 to x = 0.165. The dopants were either placed into the Si1−xGex or into the Si layers of an alternating Si/Si1−xGex layer structure. Because of the good crystal quality after growth, it was possible to obtain all luminescence data from as-grown samples without annealing. We observed a decrease in photoluminescence (PL) intensity and a stronger temperature dependence with increasing Ge content. For samples with the same Si/Si1−xGex layer structure, an enhancement of PL intensity at low temperature was seen when erbium and oxygen were placed into the Si1−xGex layers rather than into the Si layers. We attribute this effect to a capture of photogenerated carriers in the Si1−xGex layers. © 1997 American Institute of Physics.
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78.66.Li Other semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.05.Hd Other semiconductors
78.55.Hx Other solid inorganic materials

Relaxed Si0.7Ge0.3 layers grown on low-temperature Si buffers with low threading dislocation density

J. H. Li, C. S. Peng, Y. Wu, D. Y. Dai, J. M. Zhou, and Z. H. Mai

Appl. Phys. Lett. 71, 3132 (1997); http://dx.doi.org/10.1063/1.120268 (3 pages) | Cited 42 times

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Si0.7Ge0.3 epilayers with low threading dislocation density have been grown on Si (001) substrates by introducing a low temperature Si buffer. Such a structure can be used as the buffer for the growth of device structures. In comparison with the conventional compositionally graded buffer system, it has the advantages of having lower threading dislocation density, smaller thickness for required degree of relaxation, and smoother surface. Experimental evidence suggests that an anomalous relaxation mechanism has been involved.
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81.05.Hd Other semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Polarization field effects on the electron-hole recombination dynamics in In0.2Ga0.8N/In1−xGaxN multiple quantum wells

Marco Buongiorno Nardelli, Krzysztof Rapcewicz, and J. Bernholc

Appl. Phys. Lett. 71, 3135 (1997); http://dx.doi.org/10.1063/1.120269 (3 pages) | Cited 48 times

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The effect of the polarization field in wurtzite In0.2Ga0.8N/In1−xGaxN (x>0.8) multiple quantum wells is studied from first principles. The pyroelectric and piezoelectric fields naturally present in the system due to its wurtzite structure are strong enough to reduce the interband recombination rate in an ideal quantum well. We suggest that composition fluctuations, observed in the active region of actual devices, provide the necessary confinement for an improved recombination rate and lasing. © 1997 American Institute of Physics.
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73.61.Ey III-V semiconductors
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
71.20.Nr Semiconductor compounds
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.66.Fd III-V semiconductors
73.25.+i Surface conductivity and carrier phenomena
77.70.+a Pyroelectric and electrocaloric effects
77.65.Bn Piezoelectric and electrostrictive constants

Electron pump current by two pulses with phase delay

Kazuhito Tsukagoshi and Kazuo Nakazato

Appl. Phys. Lett. 71, 3138 (1997); http://dx.doi.org/10.1063/1.120270 (3 pages) | Cited 8 times

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Electron packet transport through two nodes built between three multiple-tunnel junctions (MTJs) was investigated. Two trapezoidal voltage pulses were applied to each node to transfer the electron packet. A pump current due to sequential transport of the electron packets was observed at a particular phase delay where the backward tail of the first pulse just overlapped the forward tail of the second pulse, whereas synchronized pulses could not carry the current. A dependence on pulse shape was also investigated. © 1997 American Institute of Physics.
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85.35.Ds Quantum interference devices
73.23.Hk Coulomb blockade; single-electron tunneling
73.40.Gk Tunneling

Reduction of transient diffusion from 1–5 keV Si+ ion implantation due to surface annihilation of interstitials

Aditya Agarwal, H.-J. Gossmann, D. J. Eaglesham, L. Pelaz, D. C. Jacobson, T. E. Haynes, and Yu. E. Erokhin

Appl. Phys. Lett. 71, 3141 (1997); http://dx.doi.org/10.1063/1.120552 (3 pages) | Cited 46 times

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The reduction of transient enhanced diffusion (TED) with reduced implantation energy has been investigated and quantified. A fixed dose of 1×1014 cm−2 Si+ was implanted at energies ranging from 0.5 to 20 keV into boron doping superlattices and enhanced diffusion of the buried boron marker layers was measured for anneals at 810, 950, and 1050 °C. A linearly decreasing dependence of diffusivity enhancement on decreasing Si+ ion range is observed at all temperatures, extrapolating to ∼1 for 0 keV. This is consistent with our expectation that at zero implantation energy there would be no excess interstitials from the implantation and hence no TED. Monte Carlo modeling and continuum simulations are used to fit the experimental data. The results are consistent with a surface recombination length for interstitials of <10 nm. The data presented here demonstrate that in the range of annealing temperatures of interest for p-n junction formation, TED is reduced at smaller ion implantation energies and that this is due to increased interstitial annihilation at the surface. © 1997 American Institute of Physics.
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61.72.uf Ge and Si
61.80.Jh Ion radiation effects
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
85.40.Ry Impurity doping, diffusion and ion implantation technology
61.72.Cc Kinetics of defect formation and annealing
61.72.J- Point defects and defect clusters
66.30.J- Diffusion of impurities
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Ultrafast carrier dynamics and intervalley scattering in ZnSe

D. J. Dougherty, S. B. Fleischer, E. L. Warlick, J. L. House, G. S. Petrich, L. A. Kolodziejski, and E. P. Ippen

Appl. Phys. Lett. 71, 3144 (1997); http://dx.doi.org/10.1063/1.120271 (3 pages) | Cited 12 times

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Intraband carrier dynamics were measured in ZnSe films by a two-wavelength pump probe technique with 180 fs resolution. A below-band pump pulse was used to heat carrier distributions in N-type samples by free carrier absorption. The electron cooling time constant was observed to be 500 fs. Intervalley scattering was seen to play a significant role in the electron dynamics and the scattering time from the L back to the Γ valley was measured to be 1.8 ps. By examining the ratio of the intervalley component to the total response as a function of pump photon energy, the bottom of the L valley was determined to lie 1.30 eV above the Γ-valley minimum. © 1997 American Institute of Physics.
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71.20.Nr Semiconductor compounds
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
78.47.-p Spectroscopy of solid state dynamics
71.38.-k Polarons and electron-phonon interactions
72.10.Di Scattering by phonons, magnons, and other nonlocalized excitations

Burning of high Tc bridges

M. E. Gaevski, T. H. Johansen, Yu. Galperin, H. Bratsberg, A. V. Bobyl, D. V. Shantsev, and S. F. Karmanenko

Appl. Phys. Lett. 71, 3147 (1997); http://dx.doi.org/10.1063/1.120272 (3 pages) | Cited 7 times

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Burning of superconducting thin film bridges by large transport currents (up to densities of 2×107 A/cm2) is investigated by magneto-optical imaging of flux distribution and low-temperature scanning electron microscopy providing Tc maps. It is shown that the destruction is preceded by significant penetration of magnetic field inside a weak-pinning region. In bridges containing extended defects magneto-optic investigation is sufficient to locate the incipient burning region. In high-quality bridges free from such defects only a combination of the two techniques will allow prediction of the place of fatal destruction. © 1997 American Institute of Physics.
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74.78.-w Superconducting films and low-dimensional structures
74.50.+r Tunneling phenomena; Josephson effects
74.25.Uv Vortex phases (includes vortex lattices, vortex liquids, and vortex glasses)
74.25.Sv Critical currents
74.25.Ha Magnetic properties including vortex structures and related phenomena
78.20.Ls Magneto-optical effects

Giant magnetoresistance in La0.8Sr0.2FexCo1−xO3 (0.025 ⩽ X ⩽ 0.3)

A. Barman, M. Ghosh, S. Biswas, S. K. De, and S. Chatterjee

Appl. Phys. Lett. 71, 3150 (1997); http://dx.doi.org/10.1063/1.120273 (3 pages) | Cited 8 times

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The electrical resistance and magnetoresistance of La0.8Sr0.2FexCo1−xO3 (0.025 ⩽ X ⩽ 0.3) have been studied at low temperatures down to 1.5 K and magnetic fields up to 7.5 T. The large magnetoresistance at high and low temperature has been found. The magnetoresistance exhibits a broad minima in the temperature interval between 150 and 50 K for all the compositions. The large magnetoresistance and its broad minima may be interpreted as the interplay of spin state transition, Jahn–Teller distortion, and orbital ordering of Co ions. © 1997 American Institute of Physics.
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72.20.My Galvanomagnetic and other magnetotransport effects
75.50.Dd Nonmetallic ferromagnetic materials
75.50.Pp Magnetic semiconductors
72.80.Jc Other crystalline inorganic semiconductors
72.20.Fr Low-field transport and mobility; piezoresistance
71.70.Ej Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect

Magnetic domains of cobalt ultrathin films observed with a scanning tunneling microscope using optically pumped GaAs tips

Y. Suzuki, W. Nabhan, and K. Tanaka

Appl. Phys. Lett. 71, 3153 (1997); http://dx.doi.org/10.1063/1.120274 (3 pages) | Cited 25 times

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We performed scanning tunneling microscope experiments with GaAs tips under illumination by circularly polarized light in ultrahigh vacuum at room temperature. Ferromagnetic ultrathin cobalt layers with perpendicular magnetization were employed as test samples. The spin-polarized tunneling current was shown to exhibit a magnetic sensitive component, changing its sign from one place to another on the sample surface. Reproducible images exhibiting magnetic domains of a 300–500 nm characteristic size were obtained. These results agree with magnetic force microscope measurements performed on a typical sample. © 1997 American Institute of Physics.
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75.70.Kw Domain structure (including magnetic bubbles and vortices)
75.50.Cc Other ferromagnetic metals and alloys
75.60.Ch Domain walls and domain structure
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects

Measuring hystereses of magnetic surfaces by ion scattering

M. Schleberger, M. Dirska, J. Manske, and A. Närmann

Appl. Phys. Lett. 71, 3156 (1997); http://dx.doi.org/10.1063/1.120275 (3 pages) | Cited 3 times

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Scattering of He ions off a magnetic surface results in the emission of circularly polarized light from a triplet transition. From the light polarization the spin polarization of the surface electrons can be deduced. We show that this electron capture spectroscopy (ECS) in the grazing incidence mode is an inherently surface sensitive method capable of measuring magnetic hystereses. The temperature dependence of the signal gives clear evidence that ECS is sensitive to the outermost atomic layer only. The signal follows a Bloch law with a surface prefactor of Asurf = 3.33×10−5 K−3/2. The signal as a function of the applied magnetic field results in a hysteresis which is compared to a hysteresis obtained by means of the magneto-optical Kerr effect. © 1997 American Institute of Physics.
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75.70.Rf Surface magnetism
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
78.60.Hk Cathodoluminescence, ionoluminescence
71.35.Ji Excitons in magnetic fields; magnetoexcitons
75.25.-j Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.)

Nanoscale field emission structures for ultra-low voltage operation at atmospheric pressure

A. A. G. Driskill-Smith, D. G. Hasko, and H. Ahmed

Appl. Phys. Lett. 71, 3159 (1997); http://dx.doi.org/10.1063/1.120276 (3 pages) | Cited 13 times

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Novel field emission devices with electron path lengths an order of magnitude less than the elastic mean free path of electrons in air have been fabricated and tested at atmospheric pressure. The nanoscale-tip field emission system consisted of multiple emitter tips of radii about 1 nm within an extractor aperture of diameter 50 nm. The extractor turn-on voltage was approximately 7.5 V; field-emitted currents of up to 10 nA were collected at extractor voltages of less than 10 V. Maximum current densities of over 1011 A m−2 have been observed, and the emission stability in air at atmospheric pressure is better than 3%. © 1997 American Institute of Physics.
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79.70.+q Field emission, ionization, evaporation, and desorption
85.45.Db Field emitters and arrays, cold electron emitters
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths

Control of nematic director orientation by exposing rubbed polyimide films to linearly polarized ultraviolet light

Jae-Hoon Kim, Yushan Shi, Satyendra Kumar, and Sin-Doo Lee

Appl. Phys. Lett. 71, 3162 (1997); http://dx.doi.org/10.1063/1.120277 (3 pages) | Cited 18 times

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The delicate interplay between the effects of mechanical rubbing and subsequent photo-induced chemical reactions on polyimide films has been studied for aligning liquid crystals. Exposure to linearly polarized ultraviolet (LPUV) light was found to profoundly alter the direction and the degree of molecular orientations obtained by rubbing. A simple model is presented to describe the observed changes in the director orientation. The results show that LPUV exposure can be very effectively used to control and fine-tune liquid crystal alignment. © 1997 American Institute of Physics.
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61.41.+e Polymers, elastomers, and plastics
61.30.Eb Experimental determinations of smectic, nematic, cholesteric, and other structures
64.70.M- Transitions in liquid crystals
83.80.Xz Liquid crystals: nematic, cholesteric, smectic, discotic, etc.

Microdefects in Al2O3 films and interfaces revealed by positron lifetime spectroscopy

Jun Xu, B. Somieski, L. D. Hulett, B. A. Pint, P. F. Tortorelli, R. Suzuki, and T. Ohdaira

Appl. Phys. Lett. 71, 3165 (1997); http://dx.doi.org/10.1063/1.120278 (3 pages) | Cited 3 times

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We have studied microdefects and interfaces of Al2O3 films on iron and nickel aluminide substrates using variable-energy positron lifetime spectroscopy. Di-vacancies, vacancy clusters, and microvoids were observed in the oxide scales. Their sizes and distributions were determined by the nature of the process used to synthesize the alumina film, and influenced by the composition of the alloy substrates. For oxide–iron aluminide interfaces, positron lifetimes are longer than those for the alumina layer itself, suggesting a greater defect concentration at such sites. © 1997 American Institute of Physics.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.Qq Microscopic defects (voids, inclusions, etc.)
61.72.J- Point defects and defect clusters
78.70.Bj Positron annihilation
68.35.Ct Interface structure and roughness
68.35.Dv Composition, segregation; defects and impurities

Spatial distribution of neutrons guided through a monolithic tapered lens

K. M. Podurets, V. A. Sharov, and D. F. R. Mildner

Appl. Phys. Lett. 71, 3168 (1997); http://dx.doi.org/10.1063/1.120449 (3 pages) | Cited 5 times

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The cold neutron transmission through a monolithic polycapillary lens is studied by scanning a pinhole beam across the entrance cross section of the lens. The relative transmission as a function of bending radius of a tapered channel is obtained. The results are explained in terms of a reduced critical angle for total reflection for the tapered channels. A technique for qualitative examination of monolithic lenses is proposed. © 1997 American Institute of Physics.
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28.20.Gd Neutron transport: diffusion and moderation
03.75.Be Atom and neutron optics

On stress evolution and interaction during electromigration in near bamboo structure lines

Yongkun Liu and R. J. Diefendorf

Appl. Phys. Lett. 71, 3171 (1997); http://dx.doi.org/10.1063/1.120279 (3 pages) | Cited 3 times

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Electromigration-induced stress in near bamboo structure interconnects has been simulated by the finite element method. The maximum stress at the juncture of polygranular clusters and bamboo segments increases when the stress profile interacts with the line end. The maximum stress at final steady state depends on the relative location of the polygranular cluster in the line under the constant source boundary condition. Under the blocking boundary condition, the steady state stress profile (if it exists) is determined only by current density and total line length and is independent of the microstructure of the line. Finally, the ratio of effective diffusivity of the cluster to that of bamboo segments affects the magnitude of maximum stress at quasi-steady state. © 1997 American Institute of Physics.
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66.30.Qa Electromigration
68.35.Fx Diffusion; interface formation
85.40.Ls Metallization, contacts, interconnects; device isolation

Nano-compact disks with 400 Gbit/in2 storage density fabricated using nanoimprint lithography and read with proximal probe

Peter R. Krauss and Stephen Y. Chou

Appl. Phys. Lett. 71, 3174 (1997); http://dx.doi.org/10.1063/1.120280 (3 pages) | Cited 63 times

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Nano-compact disks (Nano-CDs) with 400 Gbit/in2 topographical bit density (nearly three orders of magnitude higher than commercial CDs) have been fabricated using nanoimprint lithography. The reading and wearing of such Nano-CDs have been studied using scanning proximal probe methods. Using a tapping mode, a Nano-CD was read 1000 times without any detectable degradation of the disk or the silicon probe tip. In accelerated wear tests with a contact mode, the damage threshold was found to be 19 μN. This indicates that in a tapping mode, both the Nano-CD and silicon probe tip should have a lifetime that is at least four orders of magnitude longer than that at the damage threshold. © 1997 American Institute of Physics.
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42.79.Vb Optical storage systems, optical disks
85.40.Hp Lithography, masks and pattern transfer
81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices
42.82.Cr Fabrication techniques; lithography, pattern transfer
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