APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

1 May 2000

Volume 76, Issue 18, pp. 2487-2632

Page 1 of 2 Pages Next Page | Jump to Page
back to top
RSS Feeds

Scanning tunneling microscope light emission spectroscopy with picosecond time resolution

Y. Uehara, A. Yagami, K. J. Ito, and S. Ushioda

Appl. Phys. Lett. 76, 2487 (2000); http://dx.doi.org/10.1063/1.126384 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Scanning tunneling microscope (STM) light emission spectroscopy with picosecond time resolution has been developed and applied to the measurement of time-resolved spectra of STM light emission from an evaporated Au film. The spectra consist of two components in the time-energy domain. The first component is excited by the picosecond tunneling current pulses that are generated by picosecond laser irradiation at the STM tip-sample gap. The second component arises from the plane-wave surface plasmon polaritons that are excited at the Au surface by the laser and made radiative by the presence of the STM tip that breaks the translational symmetry of the surface. © 2000 American Institute of Physics.
Show PACS
07.79.Cz Scanning tunneling microscopes
78.47.-p Spectroscopy of solid state dynamics
78.40.Kc Metals, semimetals, and alloys
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
78.66.Bz Metals and metallic alloys
71.36.+c Polaritons (including photon-phonon and photon-magnon interactions)

Growth of Nd:potassium gadolinium tungstate thin-film waveguides by pulsed laser deposition

P. A. Atanasov, R. I. Tomov, J. Perriére, R. W. Eason, N. Vainos, A. Klini, A. Zherikhin, and E. Millon

Appl. Phys. Lett. 76, 2490 (2000); http://dx.doi.org/10.1063/1.126385 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thin Nd-doped potassium gadolinium tungstate [KGW or KGd(WO4)2] films are grown by pulsed laser deposition by ablation of a stoichiometric monocrystal target. Rutherford backscattering, x-ray diffraction, atomic force microscopy, and waveguide propagation analyses are performed. The as-grown films are optically active, as evidenced by the photoluminescence spectra centered at 1.068 μm. In some of the films, fine photoluminescence spectra between Stark levels are observed. © 2000 American Institute of Physics.
Show PACS
42.79.Gn Optical waveguides and couplers
81.15.Fg Pulsed laser ablation deposition
78.55.Hx Other solid inorganic materials
78.66.Nk Insulators
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces

Operating lifetime of phosphorescent organic light emitting devices

P. E. Burrows, S. R. Forrest, T. X. Zhou, and L. Michalski

Appl. Phys. Lett. 76, 2493 (2000); http://dx.doi.org/10.1063/1.126386 (3 pages) | Cited 71 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate the continuous operating lifetime of organic light emitting devices (OLEDs) using the phosphorescent dopant, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine platinum (II) as the light emitting molecule. We characterize devices based on two different electron transporting hosts: tris-(8-hydroxyquinoline) aluminum and 4,4′-N,N′-dicarbazolyl-biphenyl (CBP). The OLEDs lose ∼ 25% of their luminance in the first 50 h of operation, followed by extremely slow degradation with negligible growth of dark spots. The device lifetime of CBP-based phosphorescent OLEDs projected to 50% initial brightness is >107 h at a mean current density of 10 mA/cm2 under 50% duty cycle pulsed operation. These extremely long lifetimes are speculated to be an intrinsic property of electrophosphorescent OLEDs, where radiative phosphors significantly shorten the lifetime of potentially reactive triplet states in the conductive host material. © 2000 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
78.55.Kz Solid organic materials

Depletion region in thermally poled fused silica

A. L. C. Triques, C. M. B. Cordeiro, V. Balestrieri, B. Lesche, W. Margulis, and I. C. S. Carvalho

Appl. Phys. Lett. 76, 2496 (2000); http://dx.doi.org/10.1063/1.126387 (3 pages) | Cited 15 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The depletion-layer width and the recorded electric field in thermally poled fused silica are investigated experimentally as a function of the applied voltage. The depletion-layer width is observed to vary linearly with the poling voltage. The average electric field recorded in the depletion region was found to be (5.3±0.3)×108 V/m for all samples, independently of the poling voltage. © 2000 American Institute of Physics.
Show PACS
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.
77.22.Ej Polarization and depolarization
72.20.Pa Thermoelectric and thermomagnetic effects
72.80.Sk Insulators

InAs(PSb)-based “W” quantum well laser diodes emitting near 3.3 μm

A. Joullié, E. M. Skouri, M. Garcia, P. Grech, A. Wilk, P. Christol, A. N. Baranov, A. Behres, J. Kluth, A. Stein, K. Heime, M. Heuken, S. Rushworth, E. Hulicius, and T. Simecek

Appl. Phys. Lett. 76, 2499 (2000); http://dx.doi.org/10.1063/1.126388 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Mid-infrared laser diodes with an active region consisting of five “W” InAsSb/InAsP/InAsSb/InAsPSb quantum wells and broad InAsPSb waveguide were fabricated by metalorganic vapor phase epitaxy on InAs substrates. Laser emission was demonstrated at 3.3 μm up to 135 K from asymmetrical structures having n-type InAsPSb and p-type InPSb cladding layers. The devices operated in pulsed regime at 3.3 μm, with a lowest threshold current density of 120 A/cm2 at 90 K, and an output power efficiency of 31 mW/facet/A. The characteristic temperature was 35 K. © 2000 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes

Highly efficient pure blue electroluminescence from polyfluorene: Influence of the molecular weight distribution on the aggregation tendency

Karl-Heinz Weinfurtner, Hisayoshi Fujikawa, Shizuo Tokito, and Yasunori Taga

Appl. Phys. Lett. 76, 2502 (2000); http://dx.doi.org/10.1063/1.126389 (3 pages) | Cited 128 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A dependency between the molecular weight distribution of polyfluorene (PFO) and its aggregation tendency on operation in organic light-emitting devices (OLED) is described. As a result of these findings, low molecular parts of the polymer could be made responsible for the aggregation in liquid crystalline PFO. Consequently, a procedure was developed which leads to PFO-based OLEDs which do not show aggregation on operation anymore but exhibit highly efficient and stable blue electroluminescence. © 2000 American Institute of Physics.
Show PACS
78.60.Fi Electroluminescence
36.20.Cw Molecular weights, dispersity
85.60.Jb Light-emitting devices

Generation of narrow-band terahertz radiation via optical rectification of femtosecond pulses in periodically poled lithium niobate

Y.-S. Lee, T. Meade, V. Perlin, H. Winful, T. B. Norris, and A. Galvanauskas

Appl. Phys. Lett. 76, 2505 (2000); http://dx.doi.org/10.1063/1.126390 (3 pages) | Cited 84 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate a promising technique for generating narrow-band terahertz electromagnetic radiation. Femtosecond optical pulses are propagated through a periodically poled lithium-niobate crystal, where the domain length is matched to the walk-off length between the optical and THz pulses. The bandwidth of the THz wave forms is 0.11 at 1.7 THz. Optical rectification gives rise to a THz wave form which corresponds to the domain structure of the periodically poled lithium niobate. © 2000 American Institute of Physics.
Show PACS
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
84.40.-x Radiowave and microwave (including millimeter wave) technology
77.80.Dj Domain structure; hysteresis
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.22.Ej Polarization and depolarization
back to top
RSS Feeds

Self-sustained secondary discharge in inductively coupled plasma reactor

Joachim Walewski, Jussi Larjo, and Rolf Hernberg

Appl. Phys. Lett. 76, 2508 (2000); http://dx.doi.org/10.1063/1.126391 (3 pages)

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This work reports on observations of intense atomic line radiation near a substrate during diamond film growth in an inductively coupled thermal plasma. Evidence is given, indicating that the radiation is caused by electron collisions which are driven by the radio-frequency field. © 2000 American Institute of Physics.
Show PACS
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.80.-s Electric discharges
52.77.Bn Etching and cleaning
52.77.Dq Plasma-based ion implantation and deposition
81.05.Cy Elemental semiconductors
52.20.Fs Electron collisions

Plasma fluidized bed imaging and possible strong coupling effects

Hans R. Snyder, Robert P. Currier, and Michael S. Murillo

Appl. Phys. Lett. 76, 2511 (2000); http://dx.doi.org/10.1063/1.126392 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A plasma fluidized bed was constructed to study the physics of fluidized plasmas. The plasma fluidized bed is a unique system involving contact of hydrodynamically suspended micron-sized (and larger) particles with the current-carrying portion of a plasma. These particles become negatively charged and, under certain conditions, could possibly form a strongly coupled fluidized plasma. Using laser light scattering measurements, we have imaged particles and calculated a coupling parameter showing what could be strongly coupled effects superimposed on the hydrodynamic behavior of the fluidized bed systems. This system may provide an ideal means to experimentally explore the properties and dynamics of strongly coupled plasmas subjected to hydrodynamic shear forces. © 2000 American Institute of Physics.
Show PACS
52.70.Nc Particle measurements
52.30.-q Plasma dynamics and flow
back to top
RSS Feeds

Collective resonance and form factor of homogeneous broadening in semiconductors

S. V. Zaitsev, N. Yu. Gordeev, L. Ya. Karachinsky, V. I. Kopchatov, I. I. Novikov, I. S. Tarasov, N. A. Pikhtin, V. M. Ustinov, and P. S. Kop’ev

Appl. Phys. Lett. 76, 2514 (2000); http://dx.doi.org/10.1063/1.126393 (3 pages) | Cited 5 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The superradiance model was recently successfully applied to describe semiconductor quantum well luminescence spectra at low temperature (77 K). In the present work, we expand and develop this approach for room-temperature spectra and compare results with optical autocorrelation data obtained earlier. Also, the convenience of the superradiance model has been proven for precise description of cryogenic spectra of quantum dot heterostructures. Numerical analysis of quantum dot spectra allows us to conclude that homogeneous line broadening dominates over inhomogeneous one. © 2000 American Institute of Physics.
Show PACS
78.60.Fi Electroluminescence
78.45.+h Stimulated emission
78.66.Fd III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

Infrared spectroscopy of ZnSiN2 single-crystalline films on r-sapphire

Alexander Mintairov, James Merz, Andrei Osinsky, Vladimir Fuflyigin, and L. D. Zhu

Appl. Phys. Lett. 76, 2517 (2000); http://dx.doi.org/10.1063/1.126394 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter presents a study of optical phonon modes of single-crystalline orthorhombic ZnSiN2 semiconductor epitaxially deposited on r-sapphire. An epitaxial relationship for ZnSiN2 film was found from x-ray diffraction to be (0k0)ZnSiN2‖(10 math2)Al2O3 and [100]ZnSiN2‖(1math10)Al2O3. Six B1 optical modes were revealed in 400–1000 cm−1 range in s-polarized infrared reflectance spectra. This is consistent with the analysis of the phonon symmetry and selection rules presented. The frequencies of the transversal and longitudinal components, phonon damping, and oscillator strengths of the B1 phonons as well as high frequency dielectric constant ε∞xx of the orthorhombic ZnSiN2 were determined. © 2000 American Institute of Physics.
Show PACS
78.66.Li Other semiconductors
78.30.Hv Other nonmetallic inorganics
63.20.D- Phonon states and bands, normal modes, and phonon dispersion

Surface relief gratings generated by a photocrosslinkable polymer with styrylpyridine side chains

Shigeru Yamaki, Masaru Nakagawa, Shin’ya Morino, and Kunihiro Ichimura

Appl. Phys. Lett. 76, 2520 (2000); http://dx.doi.org/10.1063/1.126395 (3 pages) | Cited 15 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The formation of holographic surface relief gratings on thin films of a liquid-crystalline polymethacrylate with styrylpyridine side chains is described. A film of the polymer was treated with hydrogen chloride to protonate the side chain moieties, followed by holographic exposure to p-polarized Ar+ laser beams at 488 nm and by post-exposure baking to give rise to surface relief gratings. The depth of the surface relief in a typical case was 15 nm which is approximately 15% of the original film thickness. On the basis of the temperature dependence of diffraction efficiencies of the grating, the mechanism of the generation of the relief gratings is discussed. © 2000 American Institute of Physics.
Show PACS
42.40.Eq Holographic optical elements; holographic gratings
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials

Porous silicon microcavities as optical chemical sensors

V. Mulloni and L. Pavesi

Appl. Phys. Lett. 76, 2523 (2000); http://dx.doi.org/10.1063/1.126396 (3 pages) | Cited 77 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The optical properties of porous silicon microcavities are strongly dependent on the environment. For highly luminescent samples, both the luminescence intensity and the peak position are affected by organic substances, giving the possibility to obtain dual-parameter optical sensors. While the peak position depends on the organic compound refractive index, luminescence intensity depends on its low-frequency dielectric constant. This allows the discrimination between different organic substances. This sensor is particularly interesting for solvents with low dielectric constant, where the response of electrical sensors is very weak. © 2000 American Institute of Physics.
Show PACS
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
78.55.Mb Porous materials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.55.Ap Elemental semiconductors

Extended x-ray absorption fine-structure measurement of bond-length strain in epitaxial Gd2O3 on GaAs(001)

E. J. Nelson, J. C. Woicik, M. Hong, J. Kwo, and J. P. Mannaerts

Appl. Phys. Lett. 76, 2526 (2000); http://dx.doi.org/10.1063/1.126397 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Extended x-ray absorption fine structure (EXAFS) has been used to measure the bond length in a 23 Å epitaxial Gd2O3 film grown on GaAs(001). The Gd–O bond length is determined to be 2.390±0.013 Å, which corresponds to a +0.063±0.013 Å increase or a +2.7%±0.6% bond-length strain relative to the bond length in a bulk Gd2O3 powder. Using a simple model for the strained film that matches the [001] and [−110] axes of Gd2O3 with the [110] and [1–10] axes of the GaAs(001) surface, the measured bond-length increase of the film determined by EXAFS agrees well with the perpendicular lattice distortion of the film determined by diffraction. © 2000 American Institute of Physics.
Show PACS
68.60.Bs Mechanical and acoustical properties
61.05.cj X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.
78.70.Dm X-ray absorption spectra
68.55.-a Thin film structure and morphology

On the crystallographic characteristics of ion-beam-synthesized Ru2Si3 precipitates

G. Shao, S. Ledain, Y. L. Chen, J. S. Sharpe, R. M. Gwilliam, K. P. Homewood, K. Reeson Kirkby, and M. J. Goringe

Appl. Phys. Lett. 76, 2529 (2000); http://dx.doi.org/10.1063/1.126398 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Semiconducting Ru2Si3 precipitates have been fabricated by ion beam synthesis and a crystallographic study has been carried out using transmission electron microscopy. The results show that the orientation relationship between Ru2Si3 precipitates and Si is: 〈110〉Si∥〈111〉Ru2Si3 and {1math1}Si∥{math10}Ru2Si3, which consists of 16 independent orientation variants. © 2000 American Institute of Physics.
Show PACS
61.66.Fn Inorganic compounds
71.20.Nr Semiconductor compounds
61.72.uf Ge and Si
61.72.Cc Kinetics of defect formation and annealing
64.75.-g Phase equilibria

Parallel molecular stacks of organic thin film with electrical bistability

J. C. Li, Z. Q. Xue, X. L. Li, W. M. Liu, S. M. Hou, Y. L. Song, L. Jiang, D. B. Zhu, X. X. Bao, and Z. F. Liu

Appl. Phys. Lett. 76, 2532 (2000); http://dx.doi.org/10.1063/1.126399 (3 pages) | Cited 6 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A thin film of 1,1-dicyano-2,2-(4-dimethylaminophenyl) ethylene (DDME) has been grown by a modified vacuum deposition. The films were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and scanning tunneling microscopy (STM). Highly ordered parallel molecular stacks were repeatedly observed with STM under ambient conditions. The dc current–voltage (I–V) characteristics of device Au/DDME/Au were measured, and the film was found to possess good electrical bistability and electrochromic properties. Nanometer-scale recording was realized on the film by applying pulse voltage between the STM tip and substrate. The possible switching mechanism is discussed. © 2000 American Institute of Physics.
Show PACS
72.60.+g Mixed conductivity and conductivity transitions
73.61.Ph Polymers; organic compounds
78.66.Qn Polymers; organic compounds
68.55.-a Thin film structure and morphology
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
78.30.Jw Organic compounds, polymers
85.65.+h Molecular electronic devices
78.20.Jq Electro-optical effects

Nanometer-scale electrochemical lithography on the spinel oxide LiMn2O4

Robert Kostecki and Frank McLarnon

Appl. Phys. Lett. 76, 2535 (2000); http://dx.doi.org/10.1063/1.126400 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A scheme for nanometer-scale patterning of the surface of a conducting lithium manganese oxide (LiMn2O4) by scanning probe microscopy is described. A significant feature of this work is the demonstration that a localized surface chemical change can be confined to a depth which depends on the oxide-tip voltage bias and ambient humidity. Processing strategies exploiting this localized pattern generation vary from shallow surface property modification to localized etching of the oxide and the formation of nanometer-size pits, wells, or trenches. Unlike the scanning probe based surface oxidation of metals and semiconductors, the electroactive material is altered via electrochemically generated species. © 2000 American Institute of Physics.
Show PACS
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
81.65.Cf Surface cleaning, etching, patterning
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy
82.45.-h Electrochemistry and electrophoresis
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)

In situ barrier formation using rapid thermal annealing of a tungsten nitride/polycrystalline silicon structure

Byung Hak Lee, Kee Sun Lee, Dong Kyun Sohn, Jeong Soo Byun, Chang Hee Han, Ji-Soo Park, Sang Beom Han, and Jin Woon Park

Appl. Phys. Lett. 76, 2538 (2000); http://dx.doi.org/10.1063/1.126401 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter describes the use of rapid thermal annealing (RTA) to form a barrier layer applicable to the gate electrode in dynamic random access memory devices with a stacked structure [tungsten nitride (WNx)/polycrystalline Si (poly-Si)]. After RTA, the reactively sputtered amorphous WNx film on the poly-Si was transformed to a low-resistive α-phase W and nitrogen-segregated layer. Most of the nitrogen in the WNx film was dissipated and a relatively small amount of the nitrogen was segregated at the interface of the α-phase W and poly-Si. The segregated layer was estimated to be 2 nm thick and revealed a silicon nitride (Si–N) bonding status. More importantly, we found that this thin segregated layer successfully protected the formation of tungsten silicide, even after RTA at 1000 °C for 2 min in a hydrogen environment. © 2000 American Institute of Physics.
Show PACS
68.35.Fx Diffusion; interface formation
73.40.Ns Metal-nonmetal contacts
85.40.Ls Metallization, contacts, interconnects; device isolation
61.72.Cc Kinetics of defect formation and annealing
64.75.-g Phase equilibria
68.35.Dv Composition, segregation; defects and impurities

Experimental test for elastic compliance during growth on glass-bonded compliant substrates

P. D. Moran, D. M. Hansen, R. J. Matyi, L. J. Mawst, and T. F. Kuech

Appl. Phys. Lett. 76, 2541 (2000); http://dx.doi.org/10.1063/1.126402 (3 pages) | Cited 9 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Highly mismatched films (In0.44Ga0.56As, 3% mismatch) grown well beyond their critical thickness (to 3 μm) on GaAs glass-bonded compliant substrates exhibit surfaces four times smoother and strain distributions twice as narrow as films grown simultaneously on conventional GaAs substrates. The compliant substrates consist of a thin (∼10 nm) GaAs template layer bonded via a borosilicate glass to a mechanical handle wafer. The improvement of highly mismatched films grown well beyond their critical thickness on compliant substrate structures is commonly modeled in terms of an elastic partitioning of strain from the film to the thin (∼10 nm) single-crystal template layer. The present study is a direct test for this mechanism of elastic compliance. A comparison is reported of the strain in 92 nm In0.09Ga0.91As films and 76 nm In0.03Ga0.97As films grown simultaneously on conventional GaAs substrates and the compliant substrates responsible for the improved structural quality of In0.44Ga0.56As films. Elastic partitioning of strain from the mismatched film to the 10 nm template layer prior to the onset of misfit dislocations is not observed for films grown on these glass-bonded compliant substrates. © 2000 American Institute of Physics.
Show PACS
68.60.Bs Mechanical and acoustical properties
68.55.-a Thin film structure and morphology
81.05.Ea III-V semiconductors
81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Improvement of wet-oxidized AlxGa1−xAs (x ∼ 1) through the use of AlAs/GaAs digital alloys

G. W. Pickrell, J. H. Epple, K. L. Chang, K. C. Hsieh, and K. Y. Cheng

Appl. Phys. Lett. 76, 2544 (2000); http://dx.doi.org/10.1063/1.126403 (3 pages) | Cited 15 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A comparison of the water vapor oxidation characteristics of AlAs, Al0.98Ga0.02As, and an AlxGa1−xAs digital alloy was performed. The AlxGa1−xAs digital alloy consists of periods of 49 monolayers of AlAs and 1 monolayer of GaAs and has an equivalent composition of x = 0.98. Oxidation rates and the structural integrity of the three layers were compared. When oxidized in water vapor, the AlxGa1−xAs digital alloy and the AlAs have similar oxidation rates, both of which are twice as fast as the Al0.98Ga0.02As layer. Post-oxidation annealing of these samples at 450 °C showed severe delamination at the oxide/GaAs interface in the AlAs sample while the AlxGa1−xAs digital alloy sample was not damaged. © 2000 American Institute of Physics.
Show PACS
81.65.Mq Oxidation
81.05.Ea III-V semiconductors
61.72.Cc Kinetics of defect formation and annealing
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
68.35.Ct Interface structure and roughness

Origin of the nonradiative 〈11math0〉 line defect in lateral epitaxy-grown GaN on SiC substrates

P. Hacke, K. Domen, A. Kuramata, T. Tanahashi, and O. Ueda

Appl. Phys. Lett. 76, 2547 (2000); http://dx.doi.org/10.1063/1.126404 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nonradiative line defects are observed by cathodoluminescence in 〈math110〉 directions in [1math00]-oriented GaN stripes grown by lateral epitaxy on SiC substrates. Using transmission electron microscopy, the origin is determined to be principally screw dislocations. We observe the screw dislocations in vertically [0001] stacked configurations and forming dislocation loops and half loops contained in two of the three planes of the form {1math00}. The dislocations are believed to serve to relax the anisotropic stresses experienced in the lateral epitaxy-overgrown stripes. © 2000 American Institute of Physics.
Show PACS
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
78.66.Fd III-V semiconductors
78.60.Hk Cathodoluminescence, ionoluminescence
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
71.55.Eq III-V semiconductors
62.40.+i Anelasticity, internal friction, stress relaxation, and mechanical resonances
68.60.Bs Mechanical and acoustical properties

Time-resolved photoluminescence spectra of strong visible light-emitting SiC nanocrystalline films on Si deposited by electron-cyclotron-resonance chemical-vapor deposition

S. J. Xu, M. B. Yu, Rusli, S. F. Yoon, and C. M. Che

Appl. Phys. Lett. 76, 2550 (2000); http://dx.doi.org/10.1063/1.126382 (3 pages) | Cited 20 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
SiC nanocrystalline films on Si substrates deposited using advanced electron-cyclotron-resonance chemical-vapor deposition exhibit intense visible light emission at room temperature under laser excitation. Continuous-wave and time-resolved photoluminescence measurements for these SiC films were carried out at room temperature. The photon energy of the dominant emission peaks is higher than the band gap of cubic SiC. Room-temperature optical absorption measurements show a clear blueshift of the band gap of the samples with a decrease of the average size of the nanoclusters, indicating an expected quantum-confinement effect. However, the emission spectra are basically independent of the size. Temporal evolution of the dominant emissions exhibits double-exponential decay processes. Two distinct decay times of ∼200 ps and ∼1 ns were identified, which are at least two orders of magnitude faster than that of the bound-exciton transitions in bulk 3C–SiC at low temperature. Strong light emissions and short decay times strongly suggest that the radiative recombinations may be from some direct transitions such as self-trapped excitons on the surface of the nanoclusters. © 2000 American Institute of Physics.
Show PACS
78.55.Hx Other solid inorganic materials
78.47.-p Spectroscopy of solid state dynamics
81.07.-b Nanoscale materials and structures: fabrication and characterization
71.35.Cc Intrinsic properties of excitons; optical absorption spectra
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
71.20.Ps Other inorganic compounds
78.66.Li Other semiconductors
78.40.Ha Other nonmetallic inorganics
81.05.Hd Other semiconductors

Pulsed-laser deposition for organic electroluminescent device applications

S. R. Farrar, A. E. A. Contoret, M. O’Neill, J. E. Nicholls, A. J. Eastwood, and S. M. Kelly

Appl. Phys. Lett. 76, 2553 (2000); http://dx.doi.org/10.1063/1.126405 (3 pages)

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An anthracene-based compound has been synthesized and used in the preparation of organic light-emitting diode devices by pulsed-laser deposition. Spectrally resolved electroluminescence has been observed and combined with current–voltage measurements in an investigation of the electro-optical dependence on laser fluence and device conditioning history. The device performance has been assessed and the charge-transfer process characterized. A space-charge-limited conduction regime with an exponential distribution of traps is proposed for the elevated electric fields sufficient to produce electroluminescence. The suitability of the pulsed-laser deposition technique is evaluated for this application. Evidence for molecular degradation associated with deviation from optimum deposition parameters is provided by Fourier transform infrared spectroscopy and scanning electron microscopy observations, comparing pulsed-laser deposition with established spin-coating and physical-vapor deposition techniques. © 2000 American Institute of Physics.
Show PACS
78.60.Fi Electroluminescence
85.60.Jb Light-emitting devices
78.66.Qn Polymers; organic compounds
81.15.Fg Pulsed laser ablation deposition
73.61.Ph Polymers; organic compounds
73.50.Fq High-field and nonlinear effects
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
68.55.-a Thin film structure and morphology

Ion-beam-induced spinel-to-rocksalt structural phase transformation in MgAl2O4

Manabu Ishimaru, Ivan V. Afanasyev-Charkin, and Kurt E. Sickafus

Appl. Phys. Lett. 76, 2556 (2000); http://dx.doi.org/10.1063/1.126406 (3 pages) | Cited 19 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An ion-beam-induced metastable phase in magnesium aluminate spinel (MgAl2O4) has been examined in detail using transmission electron microscopy. Single crystals of MgAl2O4 with (111) orientation were irradiated with 180-keV Ne+ ions at 120 K to fluences of 1016 and 1017/cm2. Selected-area electron diffraction patterns obtained from the irradiation-induced damaged layer revealed that all even hkl reflections (e.g., 222) possess strong intensity, while all odd hkl reflections (e.g., 111) are weak. The features of these diffraction patterns corresponded to those of the rocksalt (NaCl) structure, suggesting that an ordered spinel to disordered rocksalt structural phase transformation in MgAl2O4 was induced by ion beam irradiation. © 2000 American Institute of Physics.
Show PACS
61.80.Jh Ion radiation effects
61.82.Ms Insulators
61.50.Ks Crystallographic aspects of phase transformations; pressure effects
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
64.70.K- Solid-solid transitions
61.66.Fn Inorganic compounds
back to top
RSS Feeds

Room-temperature minority-carrier injection-enhanced recovery of radiation-induced defects in p-InGaP and solar cells

Aurangzeb Khan, Masafumi Yamaguchi, Jacques C. Bourgoin, N. de Angelis, and Tatsuya Takamoto

Appl. Phys. Lett. 76, 2559 (2000); http://dx.doi.org/10.1063/1.126407 (3 pages) | Cited 13 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present here the direct observation of minority-carrier injection-enhanced annealing of radiation-induced defects in metalorganic chemical vapor deposition grown p-InGaP at room temperature, and the consequent recovery of radiation damage in InGaP n+-p junction solar cells. Deep level transient spectroscopy analysis shows that the main defect H2 (Ev+0.55 eV) in p-InGaP exhibits minority-carrier injection-enhanced annealing characterized by an activation energy (ΔE = 0.51 eV) close to the activation energy for the recovery (ΔE = 0.54 eV) of the defect responsible for diffusion length degradation in n+-p solar cells. The marked recovery of radiation damage in InGaP solar cells induced by minority-carrier injection is found to be correlated with the annihilation of the H2 defect. © 2000 American Institute of Physics.
Show PACS
71.55.Eq III-V semiconductors
61.82.Fk Semiconductors
84.60.Jt Photoelectric conversion
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.61.Ey III-V semiconductors
61.80.Fe Electron and positron radiation effects
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close