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

26 May 2003

Volume 82, Issue 21, pp. 3587-3793

Issue Cover Spotlight Figure

Appl. Phys. Lett. 82, 3716 (2003); http://dx.doi.org/10.1063/1.1577808 (3 pages)

V. Novosad, M. Grimsditch, J. Darrouzet, J. Pearson, S. D. Bader, V. Metlushko, K. Guslienko, Y. Otani, H. Shima, and K. Fukamichi
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Improved photoluminescence of pulsed-laser-ablated Y2O3:Eu3+ thin-film phosphors by Gd substitution

Jong Seong Bae, Jung Hyun Jeong, Soung-soo Yi, and Jung-Chul Park

Appl. Phys. Lett. 82, 3629 (2003); http://dx.doi.org/10.1063/1.1573360 (3 pages) | Cited 23 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Gd-substituted Y2−xGdxO3:Eu3+ luminescent thin films have been grown on Al2O3 (0001) substrates using pulsed-laser deposition. The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The crystallinity, surface morphology, and photoluminescence (PL) of the films are highly dependent on the amount of Gd. The PL brightness data obtained from Y2−xGdxO3:Eu3+ films grown under optimized conditions have indicated that the PL brightness is more dependent on the surface roughness than on the crystallinity of the films. In particular, the incorporation of Gd into Y2O3 lattice could induce a remarkable increase of PL. The highest emission intensity was observed with Y1.35Gd0.60Eu0.05O3, thin film whose brightness was increased by a factor of 3.1 in comparison with that of Y2O3:Eu3+ films. This phosphor has promise for application to the flat panel displays. © 2003 American Institute of Physics.
Show PACS
78.66.Nk Insulators
78.55.Hx Other solid inorganic materials
81.15.Fg Pulsed laser ablation deposition
68.35.Dv Composition, segregation; defects and impurities

Comparison of radiative and structural properties of 1.3 μm InxGa(1−x)As quantum-dot laser structures grown by metalorganic chemical vapor deposition and molecular-beam epitaxy: Effect on the lasing properties

A. Passaseo, M. De Vittorio, M. T. Todaro, I. Tarantini, M. De Giorgi, R. Cingolani, A. Taurino, M. Catalano, A. Fiore, A. Markus, J. X. Chen, C. Paranthoen, U. Oesterle, and M. Ilegems

Appl. Phys. Lett. 82, 3632 (2003); http://dx.doi.org/10.1063/1.1578182 (3 pages) | Cited 16 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have studied the radiative and structural properties of identical InxGa(1−x)As quantum dot laser structures grown by metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE). Despite the comparable emission properties found in the two devices by photoluminescence, electroluminescence, and photocurrent spectroscopy, efficient lasing from the ground state is achieved only in the MBE sample, whereas excited state lasing is obtained in the MOCVD device. Such a difference is ascribed to the existence of the internal dipole field in the MOCVD structure, induced by the strong faceting of the dots, as observed by high-resolution transmission electron microscopy. © 2003 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
78.67.Hc Quantum dots
81.07.Ta Quantum dots
68.65.Hb Quantum dots (patterned in quantum wells)
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.60.Fi Electroluminescence
73.63.Kv Quantum dots
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
79.60.Jv Interfaces; heterostructures; nanostructures

Highly uniform (Cd,Mn,Zn)Se/(Zn,Mn)Se quantum dot array formation by means of thermal treatments

T. Topuria, P. Möck, Y. Lei, and N. D. Browning

Appl. Phys. Lett. 82, 3635 (2003); http://dx.doi.org/10.1063/1.1578163 (3 pages)

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thermal treatments of (Cd,Mn,Zn)Se/(Zn,Mn)Se multiquantum well heterostructures inside the electron microscope resulted in the formation of three-dimensional CdSe based quantum dots (QDs). The array uniformity of the QDs was investigated by means of the Z-contrast imaging technique in the scanning transmission electron microscope and found to be superior to that of Stranski–Krastanow grown CdSe based QDs. The outcome of the heating experiment demonstrated that thermal treatments might be considered as one of the ways in obtaining highly ordered QD arrays. Possible mechanisms of the QD formation by means of thermal treatments are also discussed. © 2003 American Institute of Physics.
Show PACS
68.65.Hb Quantum dots (patterned in quantum wells)
81.07.Ta Quantum dots
68.37.Lp Transmission electron microscopy (TEM)
75.50.Pp Magnetic semiconductors

Spherical Nb single crystals containerlessly grown by electrostatic levitation

Y. S. Sung, H. Takeya, K. Hirata, and K. Togano

Appl. Phys. Lett. 82, 3638 (2003); http://dx.doi.org/10.1063/1.1578517 (3 pages) | Cited 11 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Spherical Nb (Tm = 2750 K) single crystals were grown via containerless electrostatic levitation (ESL). Samples became spherical at melting in levitation and undercooled typically 300–450 K prior to nucleation. As-processed samples were still spherical without any macroscopic shape change by solidification showing a uniform dendritic surface morphology. Crystallographic {111} planes exposed in equilateral triangular shapes on the surface by preferential macroetching and spotty back-reflection Laue patterns confirm the single crystal nature of the ESL-processed Nb samples. No hysteresis in magnetization between zero field and field cooling also implies a clean defect-free condition of the spherical Nb single crystals. © 2003 American Institute of Physics.
Show PACS
81.10.Fq Growth from melts; zone melting and refining
81.05.Bx Metals, semimetals, and alloys
68.47.De Metallic surfaces
81.10.Aj Theory and models of crystal growth; physics and chemistry of crystal growth, crystal morphology, and orientation
64.70.D- Solid-liquid transitions
81.30.Fb Solidification
64.60.Q- Nucleation
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
81.65.Cf Surface cleaning, etching, patterning
68.35.B- Structure of clean surfaces (and surface reconstruction)

Photoinduced phase transition of metallic SmS thin films by a femtosecond laser

R. Kitagawa, H. Takebe, and K. Morinaga

Appl. Phys. Lett. 82, 3641 (2003); http://dx.doi.org/10.1063/1.1577824 (3 pages) | Cited 9 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Metallic SmS thin films with 100–2000 nm in thickness were prepared by rf magnetron sputtering. The metallic- to semiconductor-phase transition was induced by a regeneratively amplified mode-locked Ti:sapphire laser. The shifts of the (200) peak due to the phase transition were observed by grazing incidence x-ray diffraction (GIXD) analysis. This phase transition was accompanied by the significant reflectance change of the thin films up to 45% in the near-infrared region. The depth of the phase transition layer from the surface of the film irradiated by a femtosecond laser pulse was estimated ∼200 nm from the depth profile of GIXD. © 2003 American Institute of Physics.
Show PACS
72.60.+g Mixed conductivity and conductivity transitions
79.20.Ds Laser-beam impact phenomena
68.55.Nq Composition and phase identification
78.66.-w Optical properties of specific thin films
68.55.-a Thin film structure and morphology
78.40.-q Absorption and reflection spectra: visible and ultraviolet
61.72.S- Impurities in crystals
61.82.-d Radiation effects on specific materials

Tuning the structural and optical properties of 1.3-μm InAs/GaAs quantum dots by a combined InAlAs and GaAs strained buffer layer

H. Y. Liu and M. Hopkinson

Appl. Phys. Lett. 82, 3644 (2003); http://dx.doi.org/10.1063/1.1577827 (3 pages) | Cited 20 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A combined InAlAs and GaAs strained buffer layer was presented to tailor the structural and optical properties of 1.3-μm InAs/GaAs quantum dots. This growth technique exhibits an increment of InAs quantum-dot density from 1.6×1010 to 2.8×1010 cm−2 and an improvement of energy separation between the quantum-dot ground and first-excited states from 84 to 93 meV upon adjusting the thickness of GaAs in InAlAs–GaAs buffer layer. We also investigate the effect of an InAlAs layer surrounding InAs quantum dots on photoluminescence intensity with increasing the thickness of InAlAs layer in a 6-nm InAlAs–InGaAs composite cap layer, and no negative effect has been observed. © 2003 American Institute of Physics.
Show PACS
68.65.Hb Quantum dots (patterned in quantum wells)
78.67.Hc Quantum dots
81.07.Ta Quantum dots
73.21.La Quantum dots
78.55.Cr III-V semiconductors
68.37.Ps Atomic force microscopy (AFM)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Boron uphill diffusion during ultrashallow junction formation

R. Duffy, V. C. Venezia, A. Heringa, T. W. T. Hüsken, M. J. P. Hopstaken, N. E. B. Cowern, P. B. Griffin, and C. C. Wang

Appl. Phys. Lett. 82, 3647 (2003); http://dx.doi.org/10.1063/1.1578512 (3 pages) | Cited 41 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The recently observed phenomenon of boron uphill diffusion during low-temperature annealing of ultrashallow ion-implanted junctions in silicon has been investigated. It is shown that the effect is enhanced by preamorphization, and that an increase in the depth of the preamorphized layer reduces uphill diffusion in the high-concentration portion of boron profile, while increasing transient enhanced diffusion in the tail. The data demonstrate that the magnitude of the uphill diffusion effect is determined by the proximity of boron and implant damage to the silicon surface. © 2003 American Institute of Physics.
Show PACS
66.30.J- Diffusion of impurities
81.05.Cy Elemental semiconductors
61.72.uf Ge and Si
61.72.S- Impurities in crystals
68.35.Fx Diffusion; interface formation
68.47.Fg Semiconductor surfaces
61.80.Jh Ion radiation effects
61.82.Fk Semiconductors
85.40.Ry Impurity doping, diffusion and ion implantation technology
61.72.Cc Kinetics of defect formation and annealing

Transient-enhanced Si diffusion on native-oxide-covered Si(001) nanostructures during vacuum annealing

H. Lichtenberger, M. Mühlberger, and F. Schäffler

Appl. Phys. Lett. 82, 3650 (2003); http://dx.doi.org/10.1063/1.1577391 (3 pages) | Cited 11 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the transient-enhanced shape transformation of nanostructured Si(001) surfaces upon in vacuo annealing at relatively low temperatures of 900–950 °C for a few minutes. We find dramatic surface mass transport concomitant with the development of low-energy facets on surfaces that are covered by native oxide. The enhanced surface mass transport ceases after the oxide is completely desorbed, and it is also not observed on surfaces where the native oxide had been removed by HF before annealing. © 2003 American Institute of Physics.
Show PACS
68.35.Fx Diffusion; interface formation
68.47.Fg Semiconductor surfaces
61.46.-w Structure of nanoscale materials
61.72.Cc Kinetics of defect formation and annealing
68.35.Rh Phase transitions and critical phenomena
68.43.Mn Adsorption kinetics

Nanostructured silicon formations as a result of ionized N2 gas reactions on silicon with native oxide layers

Min-Cherl Jung, Tae Gyoung Lee, Young Ju Park, Sung Ho Jun, Joosang Lee, Moonsup Han, Jong Seok Jeong, and Jeong Yong Lee

Appl. Phys. Lett. 82, 3653 (2003); http://dx.doi.org/10.1063/1.1579124 (3 pages) | Cited 3 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nanostructured silicon was formed by means of the ionized N2 gas reaction on SiO2/Si, and the electronic structure, surface morphology, and optical properties were investigated. The physicochemically modified thin layers were resolved to SiNy and SiOxNy through the observation of Si 2p, O 1s, and N 1s core-level spectra in x-ray photoelectron spectroscopy. The formations of SiOxNy and SiO2 nanostructures (3–4 nm in size), performed by the etching process followed by adsorption of ionized nitrogen, were confirmed by atomic force microscopy. The nanocrystalline Si (6 nm in size) distributed within the modified layer (approximately 10 nm thick) was observed after the in situ rapid thermal annealing processes, using high-resolution transmission electron microscopy. Photoluminescence with a wavelength peaking at around 400 nm was emitted from the nanocrystalline Si formed from the SiOxNy/SiO2/Si structures. This work suggests that the nanocrystalline-Si formation and the nanostructured surface modification method, using the controlled ionized gas, were simple and efficient methods requiring low energy and low temperatures. © 2003 American Institute of Physics.
Show PACS
81.65.-b Surface treatments
68.47.Fg Semiconductor surfaces
81.05.Cy Elemental semiconductors
81.16.-c Methods of micro- and nanofabrication and processing
78.55.Ap Elemental semiconductors
68.43.Fg Adsorbate structure (binding sites, geometry)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
61.82.Fk Semiconductors
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.72.Cc Kinetics of defect formation and annealing
68.37.Lp Transmission electron microscopy (TEM)
68.37.Ps Atomic force microscopy (AFM)
79.60.Dp Adsorbed layers and thin films
73.20.Hb Impurity and defect levels; energy states of adsorbed species
68.35.B- Structure of clean surfaces (and surface reconstruction)
81.07.Bc Nanocrystalline materials
73.22.-f Electronic structure of nanoscale materials and related systems
61.82.Rx Nanocrystalline materials
61.46.-w Structure of nanoscale materials

Interface structure and chemistry in ZnSe/Ga1−xMnxAs/ZnSe heterostructures

G. D. Lian, E. C. Dickey, S. H. Chun, K. C. Ku, and N. Samarth

Appl. Phys. Lett. 82, 3656 (2003); http://dx.doi.org/10.1063/1.1577825 (3 pages) | Cited 1 time

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The structure and chemical composition of ZnSe/Ga1−xMnxAs/ZnSe multilayers grown on (100) GaAs substrates are investigated by high-resolution transmission electron microscopy imaging and spectroscopy techniques. While all layers grow epitaxially and the Ga1−xMnxAs layer is free of planar defects, a high density of stacking faults is observed in the ZnSe layer over Ga1−xMnxAs. The composition of the ferromagnetic layer is measured to be Ga0.93Mn0.07As, and the Mn valence was determined to be 2+. Compositional profiles across the interfaces quantified by electron energy-loss spectroscopy show that the ZnSe/Ga1−xMnxAs interfaces are wider than the ZnSe/GaAs–substrate interface, which is mainly attributed to interfacial roughness. © 2003 American Institute of Physics.
Show PACS
68.65.Ac Multilayers
75.50.Pp Magnetic semiconductors
75.50.Dd Nonmetallic ferromagnetic materials
68.35.Ct Interface structure and roughness
68.37.Lp Transmission electron microscopy (TEM)
79.20.Uv Electron energy loss spectroscopy
61.72.Nn Stacking faults and other planar or extended defects
75.70.Cn Magnetic properties of interfaces (multilayers, superlattices, heterostructures)

Cubic local order around Al and intermixing in short-period AlN/TiN multilayers studied by Al K-edge extended x-ray absorption fine structure spectroscopy and x-ray diffraction

O. Ersen, M.-H. Tuilier, O. Thomas, P. Gergaud, and P. Lagarde

Appl. Phys. Lett. 82, 3659 (2003); http://dx.doi.org/10.1063/1.1578692 (3 pages) | Cited 9 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Al K-edge extended x-ray absorption fine structure (EXAFS) experiments are performed on short-period TiN (50 nm)/AlN (Λ = 1, 2, 3, 5, and 15 nm) multilayers prepared by dc magnetron sputtering on MgO(100). It is shown that the local order around Al is hexagonal down to Λ = 3 nm and becomes clearly cubic B1 rocksalt-type below this thickness. This phase transition is correlated with x-ray diffraction results, which reveal increased compressive stresses in TiN layers for Λ = 3 nm. In addition, EXAFS provides direct evidence of substitution of Ti for Al within AlN layers, as well as an estimation of Ti content as a function of layer thickness. © 2003 American Institute of Physics.
Show PACS
68.35.Fx Diffusion; interface formation
68.65.Cd Superlattices
78.70.Dm X-ray absorption spectra
64.70.K- Solid-solid transitions

Hydrogen-induced improvements in optical quality of GaNAs alloys

I. A. Buyanova, M. Izadifard, W. M. Chen, A. Polimeni, M. Capizzi, H. P. Xin, and C. W. Tu

Appl. Phys. Lett. 82, 3662 (2003); http://dx.doi.org/10.1063/1.1578513 (3 pages) | Cited 23 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Strong suppression of potential fluctuations in the band edges of GaNAs alloys due to postgrowth hydrogen treatment, which is accompanied by a reopening of the alloy band gap, is revealed from temperature-dependent photoluminescence (PL) and PL excitation measurements. The effect likely indicates preferential trapping of hydrogen near the lattice sites with the highest nitrogen content. A remarkable improvement in the radiative efficiency of the alloys at room temperature is also demonstrated and is ascribed to efficient hydrogen passivation of competing nonradiative centers. © 2003 American Institute of Physics.
Show PACS
78.55.Cr III-V semiconductors
71.55.Eq III-V semiconductors
71.20.Nr Semiconductor compounds
78.67.De Quantum wells
78.66.Fd III-V semiconductors
73.21.Fg Quantum wells

Increasing medium-range order in amorphous silicon with low-energy ion bombardment

J. E. Gerbi, P. M. Voyles, M. M. J. Treacy, J. M. Gibson, and J. R. Abelson

Appl. Phys. Lett. 82, 3665 (2003); http://dx.doi.org/10.1063/1.1578164 (3 pages) | Cited 21 times

Online Publication Date: 20 May 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have observed the existence of medium–range order in amorphous silicon with the fluctuation electron microscopy technique. We hypothesize that this structure is produced during the highly nonequilibrium deposition process, during which nuclei are formed and subsequently buried. We test this hypothesis by altering the deposition kinetics during magnetron sputter deposition by bombarding the growth surface with a variable flux of low-energy (20 eV) Ar+ ions. We observe that medium–range order increases monotonically as the ion/neutral flux ratio increases. We suggest that this low-energy bombardment increases adspecie surface mobility or modifies local structural rearrangements, resulting in enhanced medium–range order via increases in the size, volume fraction, and/or internal order of the nuclei. © 2003 American Institute of Physics.
Show PACS
61.43.Dq Amorphous semiconductors, metals, and alloys
61.80.Jh Ion radiation effects
61.82.Fk Semiconductors
81.05.Gc Amorphous semiconductors
68.55.-a Thin film structure and morphology
81.15.Cd Deposition by sputtering
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close