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

19 Jan 1998

Volume 72, Issue 3, pp. 269-391

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

Near diffraction-limited laser emission from a polymer in a high finesse planar cavity

A. Schülzgen, Ch. Spiegelberg, M. M. Morrell, S. B. Mendes, B. Kippelen, N. Peyghambarian, M. F. Nabor, E. A. Mash, and P. M. Allemand

Appl. Phys. Lett. 72, 269 (1998); http://dx.doi.org/10.1063/1.120709 (3 pages) | Cited 23 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report near diffraction-limited laser emission from the conjugated polymer BEH:PPV in a cavity made with two dielectric mirrors providing a high finesse planar cavity. The laser has a sharp intensity threshold, a strong directionality, and a high degree of polarization. These emission characteristics are compared with those of a single polymer layer without optical feedback. © 1998 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.79.Bh Lenses, prisms and mirrors

Nonlinear optical effects in ferrofluids induced by temperature and concentration cross coupling

Tengda Du and Weili Luo

Appl. Phys. Lett. 72, 272 (1998); http://dx.doi.org/10.1063/1.120710 (3 pages) | Cited 25 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Both experiment and numerical calculation were performed to study the nonlinear optical (NLO) effects in ferrofluids consisting of magnetic particles suspended in an organic solvent. We show that, in contrast to all the mechanisms responsible for NLO phenomena known so far, the novel NLO effects in ferrofluids in the zero applied field can be explained by the cross coupling between the temperature of the system and the concentration of particles through thermophoresis, which in turn leads to the spatial distribution of the refractive index. This NLO effect is enhanced by applying a moderate magnetic field whose mechanism is unclear so far. © 1998 American Institute of Physics.
Show PACS
42.65.-k Nonlinear optics
75.50.Mm Magnetic liquids
75.50.Tt Fine-particle systems; nanocrystalline materials
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
78.20.Ls Magneto-optical effects
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.20.N- Thermo-optic effects
78.20.nb Photothermal effects

Mapping of the lateral polar orientational distribution in second-order nonlinear thin films by scanning second-harmonic microscopy

Jan Vydra and Manfred Eich

Appl. Phys. Lett. 72, 275 (1998); http://dx.doi.org/10.1063/1.120711 (3 pages) | Cited 16 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a nondestructive experimental technique for the determination of the lateral distribution of the polar order in second-order nonlinear optical thin films. The sample, which consists of a poled polymer film is scanned through the focus of an infrared laser beam in a second-harmonic generation setup and the second-harmonic intensity is monitored stepwise. In combination with a conventional electro-optic (EO) characterization it is possible to create an EO-coefficient map of the sample. The resolution of this mapping technique can be significantly increased by using high numerical aperture microscope optics for the illumination of the poled polymer. This method, for instance, allows the evaluation of poling inhomogeneities due to high-field poling and field distortions at the edges of poling electrodes. © 1998 American Institute of Physics.
Show PACS
61.41.+e Polymers, elastomers, and plastics
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Qn Polymers; organic compounds
42.70.Jk Polymers and organics
68.55.-a Thin film structure and morphology
78.20.Jq Electro-optical effects

Fiber array targets for producing long media of high gain in recombination-pumped soft-x-ray lasers

Tsuneyuki Ozaki and Hiroto Kuroda

Appl. Phys. Lett. 72, 278 (1998); http://dx.doi.org/10.1063/1.120712 (3 pages) | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate a target for recombination-pumped soft-x-ray lasers, consisting of an equally spaced array of parallel fibers. This target is capable of producing long media of several centimeters, and can also generate high gain due to the initial two-dimensional expansion of the plasma. Numerical simulations show that amplification occurs after the plasma expansion changes from a cylindrical to a slablike one, as a result of collisions with plasma produced from neighboring fibers. Initial gain measurements using graphite-coated fiber array targets reveal Balmer α gain coefficients of 4.1 cm−1. © 1998 American Institute of Physics.
Show PACS
42.55.Vc X- and γ-ray lasers
42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.By Design of specific laser systems

Improvement of short pulse operation of AlGaAs quantum-well lasers by temperature increase

I. Y. Khrushchev, I. H. White, and R. V. Penty

Appl. Phys. Lett. 72, 281 (1998); http://dx.doi.org/10.1063/1.120748 (3 pages)

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A theoretical model has been formulated using lumped rate equations to analyze the temperature dependence of the Q-switched (i.e., saturable absorber operated) and gain-switched operation of a quantum-well laser. The results are found to agree with experimental results obtained from AlGaAs quantum-well devices, and show that improvement in the pulse energy in Q-switched and gain-switched lasers can be achieved by optimizing the operating temperature above room temperature. With increasing temperature, the pulse energy increases due to the pulses broadening while the peak power remains approximately constant. The effect is mainly attributed to the decrease of the gain with temperature. © 1998 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Wide-band suppression of photon-number fluctuations in a high-speed light-emitting diode driven by a constant-current source

M. Kobayashi, M. Kohno, Y. Kadoya, M. Yamanishi, J. Abe, and T. Hirano

Appl. Phys. Lett. 72, 284 (1998); http://dx.doi.org/10.1063/1.120713 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate experimental results on the generation of sub-Poissonian photon fluxes emanating from an AlGaAs light-emitting diode, which manifest a wide-band (0–100 MHz) noise suppression below the standard quantum limit level despite low current density ( ∼ 38 A/cm2) operation at room temperature. The experimental noise power spectrum is well fitted in terms of the theoretical curve estimated with the quantum mechanical Langevin equations. © 1998 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
02.50.-r Probability theory, stochastic processes, and statistics
85.30.De Semiconductor-device characterization, design, and modeling
42.50.Lc Quantum fluctuations, quantum noise, and quantum jumps

Many-body optical gain of wurtzite GaN-based quantum-well lasers and comparison with experiment

Seoung-Hwan Park and Shun-Lien Chuang

Appl. Phys. Lett. 72, 287 (1998); http://dx.doi.org/10.1063/1.120714 (3 pages) | Cited 36 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The optical gain of wurtzite InxGa1−xN/In0.02Ga0.98N and GaN/AlxGa1−xN quantum well (QW) lasers taking into account many-body effects is investigated. The valence band structures are calculated as a function of strain and well thickness. The inclusion of compressive strain shows better lasing performance because of the increase of the subband energy separation in the valence band. Our theoretical gain spectra of In0.15Ga0.85N/In0.02Ga0.98N QW lasers are in good agreement with measured ones reported by Nakamura, IEEE J. Sel. Top. Quantum Electron. 3, 712 (1997). It is also shown that there is a universal relation governing the dependence of the band-gap renormalization on the two-dimensional carrier density for GaN-based QW lasers as there is for the infrared III-V systems. © 1998 American Institute of Physics.  
Show PACS
42.55.Px Semiconductor lasers; laser diodes
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
68.60.Bs Mechanical and acoustical properties
back to top
RSS Feeds

Characterization of the negative ion fraction in high-density SF6 magnetoplasmas using ion acoustic waves

L. St-Onge, J. Margot, and M. Chaker

Appl. Phys. Lett. 72, 290 (1998); http://dx.doi.org/10.1063/1.120715 (3 pages) | Cited 14 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Most plasmas used in the microelectronics industry are electronegative, i.e., they contain a large number of negative ions. One simple way to characterize the negative-to-positive ion density ratio (n−/n+) in such plasmas is to measure the velocity of ion acoustic waves (IAWs). In this letter, a detailed study of the propagation of IAWs in high-density SF6 magnetoplasmas is given. Results (n−/n+) obtained by way of this technique as functions of different parameters (gas pressure, SF6 content in SF6/Ar mixture, and radial position in the reactor) are compared to those obtained with a more sophisticated technique based on laser photodetachment. © 1998 American Institute of Physics.
Show PACS
52.35.Fp Electrostatic waves and oscillations (e.g., ion-acoustic waves)
52.27.Jt Nonneutral plasmas
52.25.-b Plasma properties
back to top
RSS Feeds

Photochemical and thermal effects in laser irradiated fullerite: From periodic exfoliation to cone formation

P. Milani, C. E. Bottani, A. Parisini, and G. P. Banfi

Appl. Phys. Lett. 72, 293 (1998); http://dx.doi.org/10.1063/1.120716 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report a characterization of fullerite surface modification by cumulative laser irradiation. We show that the nano- and mesostructure of the transformed material are related and that they depend on the laser wavelength and fluence. Irradiating the sample at 1064 nm we observe periodic exfoliation of the transformed surface which is composed, on a nanometer scale, of a network of graphitic elongated nanoparticles. Under UV irradiation, the nanostructure is characterized by tangled graphene layers and cone formation is observed on a mesoscopic scale. Our observations show that different destabilization mechanisms of C60 produce coalescence pathways towards different nanostructures and mesoscopic morphologies. © 1998 American Institute of Physics.
Show PACS
61.48.-c Structure of fullerenes and related hollow and planar molecular structures
81.05.ub Fullerenes and related materials
68.35.B- Structure of clean surfaces (and surface reconstruction)
79.20.Ds Laser-beam impact phenomena

Formation of the precursor for diamond growth by in situ direct current glow discharge pretreatment

I. Gouzman, I. Lior, and A. Hoffman

Appl. Phys. Lett. 72, 296 (1998); http://dx.doi.org/10.1063/1.120747 (3 pages) | Cited 23 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A direct current (dc) glow discharge—surface interaction process for in situ substrate surface pretreatment, for the promotion of diamond growth on mirror polished Si(100) is reported. A key step of the pretreatment is a generation of a stable dc-glow discharge between a grounded substrate and a positively biased electrode using a CH4/H2 gas mixture. During this stage, no additional gas phase activation by a hot filament is carried out. For subsequent diamond deposition, the dc-glow discharge is switched off and the standard hot filament CVD growth conditions are applied. The nature of the deposits formed by the dc-glow discharge process and after standard diamond deposition conditions, are investigated by Raman spectroscopy and high resolution scanning electron microscopy. It is found that the properties of the films, deposited following the dc-glow discharge pretreatment, strongly depend on the pretreatment conditions: methane concentration, substrate temperature, and pretreatment time. It is suggested that the nature of the diamond precursor formed during the dc-glow discharge pretreatment is similar to that one observed after bias enhanced nucleation process. © 1998 American Institute of Physics.
Show PACS
81.05.ub Fullerenes and related materials
81.05.Cy Elemental semiconductors
52.77.Bn Etching and cleaning
52.77.Dq Plasma-based ion implantation and deposition
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
85.40.Sz Deposition technology

Phase formation and ferroelectricity of sol-gel derived (Pb, La)TiO3 thin films

Su Jae Lee, Kwang Yong Kang, Seok Kil Han, Min Su Jang, Byung Gyu Chae, Yong Suk Yang, and Seong Hyun Kim

Appl. Phys. Lett. 72, 299 (1998); http://dx.doi.org/10.1063/1.120717 (3 pages) | Cited 34 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ferroelectric lead lanthanum titanate (PLT) thin films with various lanthanum concentration were fabricated by sol-gel spin-on process onto Pt/Ti/SiO2/Si substrates. We investigated the crystal structure, microstructure, and dielectric and ferroelectric properties of PLT films according to lanthanum doping concentration. The films annealed at 600 °C for 30 min have the single perovskite phase having only tetragonal or pseudocubic structure. The film microstructures were changed according to the doping concentration of La. The PLT films showed the typical polarization-electric field hysteresis loops and capacitance-voltage characteristics representing the ferroelectric switching property. The coercive field and remanent polarization decreased due to the phase transformation from ferroelectric to paraelectric phase with increasing La concentration. The effective dielectric constant and the leakage current density increased according to the increase of La content. © 1998 American Institute of Physics.
Show PACS
77.80.Dj Domain structure; hysteresis
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films
77.80.Fm Switching phenomena
81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)
77.22.Ej Polarization and depolarization
77.22.Ch Permittivity (dielectric function)

Poole–Frenkel effect assisted emission from deep donor level in chromium doped GaP

R. Ajjel, M. A. Zaidi, S. Alaya, G. Brémond, G. Guillot, and J. C. Bourgoin

Appl. Phys. Lett. 72, 302 (1998); http://dx.doi.org/10.1063/1.120718 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The electrical properties of chromium-related defects in GaP are investigated. Using deep-level transient spectroscopy, a related deep level is observed in p-type GaP exhibiting an activation energy, associated with hole emission, of 0.5 eV. Detailed capacitance transient investigations were undertaken to study the electric field dependence. This emission rate which is found to have a field dependence can be fitted by a Poole–Frenkel model. Evidence is given that the trap is the Cr4+/3+ deep donor level in GaP caused by substitutional Cr on Ga sites. This trap seems to be well adapted to compensate donors for the growth of the semi-insulating GaP. © 1998 American Institute of Physics.
Show PACS
71.55.Eq III-V semiconductors
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
72.80.Ey III-V and II-VI semiconductors
72.20.Ht High-field and nonlinear effects

Trapping of size-selected Ag clusters at surface steps

S. J. Carroll, K. Seeger, and R. E. Palmer

Appl. Phys. Lett. 72, 305 (1998); http://dx.doi.org/10.1063/1.120719 (3 pages) | Cited 31 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have investigated the deposition of size-selected metal clusters (Ag400) onto a stepped graphite surface. The clusters were produced with an inert gas condensation cluster source and were imaged on the surface with a high-resolution scanning electron microscope. For modest cluster deposition energies, cluster aggregation is much more limited at the steps than on the flat terrace regions of the surface, suggesting the possibility of the fabrication of structured arrays (e.g., chains) of size-selected particles. A theoretical analysis of the particle-particle gap size distribution along the step probes the 1D mobility of the particles trapped at the step. © 1998 American Institute of Physics.
Show PACS
61.46.-w Structure of nanoscale materials
68.03.Fg Evaporation and condensation of liquids
68.43.Mn Adsorption kinetics
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.55.-a Thin film structure and morphology
64.75.-g Phase equilibria
68.35.Fx Diffusion; interface formation

180° ferroelectric domains in polycrystalline BaTiO3 thin films

In-Tae Kim, Jin Wook Jang, Hyuk-Joon Youn, Chang Hoon Kim, and Kug Sun Hong

Appl. Phys. Lett. 72, 308 (1998); http://dx.doi.org/10.1063/1.120720 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The presence of 180° ferroelectric domains in polycrystalline BaTiO3 thin films has been observed with the aid of transmission electron microscopy. The 180° domain boundary exhibited a curved appearance, and its orientational relationship was demonstrated. It was found that equiaxial grains did not have 180° domain boundaries due to their higher boundary energy. The grain size effect on dielectric constant of polycrystalline BaTiO3 thin films was also discussed in conjunction with 180° ferroelectric domains. © 1998 American Institute of Physics.
Show PACS
77.80.Dj Domain structure; hysteresis
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films

Alignment of misfit dislocations in the In0.52Al0.48As/InxGa1−xAs/In0.52Al0.48As/InP heterostructure

J. Wu, H. X. Li, T. W. Fan, and Z. G. Wang

Appl. Phys. Lett. 72, 311 (1998); http://dx.doi.org/10.1063/1.120721 (3 pages)

Full Text: Read Online (HTML) | Download PDF

Show Abstract
It was observed with transmission electron microscopy in the In0.52Al0.48As/InxGa1−xAs/In0.52Al0.48As system grown on the (001) InP substrate that misfit dislocation lines deviate 〈110〉 directions at an angle with its value depending on the gallium content. Such an abnormal alignment of misfit dislocations is explained in terms of an alloy effect on the formation of single jogs on misfit dislocations in the interface between the III–V ternary compounds. © 1998 American Institute of Physics.
Show PACS
81.05.Ea III-V semiconductors
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
68.35.Ct Interface structure and roughness

Formation of BN nanoarches: Possibly the key to cubic boron nitride film growth

C. Collazo-Davila, E. Bengu, C. Leslie, and L. D. Marks

Appl. Phys. Lett. 72, 314 (1998); http://dx.doi.org/10.1063/1.120722 (3 pages) | Cited 20 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The formation of epitaxial nanotubes (nanoarches) on the surface of hexagonal BN (h-BN) during electron irradiation is reported. In addition to implications in terms of understanding fullerene based structures, we suggest that these act as the nucleation sites for cubic BN (c-BN) growth and may lead to improved film growth. We also report a strong dependence upon the microscope vacuum, which may be critical in understanding irreproducibility in film growth. © 1998 American Institute of Physics.
Show PACS
61.46.-w Structure of nanoscale materials
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.07.-b Nanoscale materials and structures: fabrication and characterization
61.80.Fe Electron and positron radiation effects
68.55.-a Thin film structure and morphology

Variation of the relative permittivity of charged dielectrics

C. K. Ong, Z. G. Song, K. H. Oh, H. Gong, and C. Le Gressus

Appl. Phys. Lett. 72, 317 (1998); http://dx.doi.org/10.1063/1.120723 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The variation of the relative permittivity of charged dielectrics with trapped charge density has been investigated by a time-resolved current method, in conjunction with a mirror image method employing a scanning electron microscope. The calculation is made by a mathematical expression derived from classical electromagnetic theory. It is found that the relative permittivity of the charged area in the polymethylmethacrylate sample increases with the trapped charge density and saturates at a certain value of the trapped charge density. These observations have been discussed by analogy with the dielectric saturation occurring at a high applied external electric field. © 1998 American Institute of Physics.
Show PACS
77.84.Jd Polymers; organic compounds
77.22.Ch Permittivity (dielectric function)

Nanometer-scale germanium islands on Si(111) surface windows formed in an ultrathin silicon dioxide film

Alexander A. Shklyaev, Motoshi Shibata, and Masakazu Ichikawa

Appl. Phys. Lett. 72, 320 (1998); http://dx.doi.org/10.1063/1.120724 (3 pages) | Cited 23 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Three-dimensional Ge islands between 15 and 200 nm in size were found to grow only on Si(111) surface windows in ultrathin SiO2 film after Ge deposition and subsequent SiO2 decomposition. The size of Ge islands gradually decreased as the Ge thickness decreased. Pseudomorphic two-dimensional Ge layers with the 5×5 structure formed in surrounding areas of the windows. The windows were produced by selective thermal SiO2 decomposition induced by focused electron beam irradiation. These results suggest a new technique for nanometer-scale Ge island fabrication at given points on Si surfaces. © 1998 American Institute of Physics.
Show PACS
81.05.Cy Elemental semiconductors
61.46.-w Structure of nanoscale materials
81.07.-b Nanoscale materials and structures: fabrication and characterization
68.55.-a Thin film structure and morphology
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Electron-beam damage of C60 films on hydrogen-passivated Si(100)

Michael R. C. Hunt, Jens Schmidt, and Richard E. Palmer

Appl. Phys. Lett. 72, 323 (1998); http://dx.doi.org/10.1063/1.120725 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the effects of medium-energy (3.5 keV) electron-beam irradiation of C60 films between 1 and 4 ML thick grown on Si(100) 2×1-H studied by high-resolution electron energy-loss spectroscopy. Electron irradiation leads primarily to molecular fragmentation. Initially, molecular fragments are discrete, and saturated with hydrogen, but continued irradiation leads to the formation of a disordered material with a graphitic local structure. Experiments performed on a single monolayer of C60 show that under irradiation, fragments can bond to the substrate via displacement or desorption of the hydrogen atoms bonded to the Si substrate. © 1998 American Institute of Physics.
Show PACS
61.48.-c Structure of fullerenes and related hollow and planar molecular structures
81.05.ub Fullerenes and related materials
61.80.Fe Electron and positron radiation effects
79.20.Kz Other electron-impact emission phenomena
61.82.Pv Polymers, organic compounds

Linewidth and underlayer influence on texture in submicrometer-wide Al and AlCu lines

J. L. Hurd, K. P. Rodbell, L. M. Gignac, L. A. Clevenger, R. C. Iggulden, R. F. Schnabel, S. J. Weber, and N. H. Schmidt

Appl. Phys. Lett. 72, 326 (1998); http://dx.doi.org/10.1063/1.120726 (3 pages) | Cited 9 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The local texture in three types of patterned, thin-film, Al and AlCu interconnections on Si semiconductor devices is investigated by electron backscatter diffraction. Two types of standard planar metal structures were investigated: (1) blanket Al and (2) blanket Al–0.5 wt % Cu on TiN/Ti underlayers. Both were deposited on amorphous SiO2 substrates followed by reactive ion etching to define 0.45–10 μm wide lines and >10×10 μm2 pads. Damascene structures were also investigated in which Al–0.5 wt % Cu films were deposited into preformed Ti-lined amorphous SiO2 trenches, 0.3–5.0 μm wide by 0.4 μm deep, followed by chemical–mechanical polishing to remove the metal overburden. For these three types of structures, distinctly different behaviors were observed: the two planar metal samples exhibited either little change or a large increase in their (111) fiber texture strength with decreasing linewidth, while the damascene samples showed a marked decrease in the (111) fiber texture with decreasing linewidth and feature size. In addition, a novel trimodal (111) texture distribution was found in 0.3 μm wide damascene lines in which appreciable TiAl3 formed. © 1998 American Institute of Physics.
Show PACS
85.40.Ls Metallization, contacts, interconnects; device isolation
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization
81.65.Cf Surface cleaning, etching, patterning
81.65.Ps Polishing, grinding, surface finishing
52.77.Bn Etching and cleaning
52.77.Dq Plasma-based ion implantation and deposition
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology

Determination of the unified surface-anchoring energy of a nematic liquid crystal on a polymer substrate

Akihiko Sugimura, Tetsuo Miyamoto, Makoto Tsuji, and Michiyoshi Kuze

Appl. Phys. Lett. 72, 329 (1998); http://dx.doi.org/10.1063/1.120727 (3 pages) | Cited 27 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A saturation voltage method is described for determining the unified surface-anchoring energy, which has been proposed theoretically by Sugimura and co-workers [Phys. Rev. E, 52, 681 (1995)], at the interface of nematic (4-pentyl-4′-cyanobiphenyl) and its alignment layer (polyvinyl cinnamate). The method proposed can be employed as a standard measure of this energy without any additional numerical calculation. A conventional measurement method of an optical retardation from a liquid crystal slab is used to estimate the saturation voltage. © 1998 American Institute of Physics.
Show PACS
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order

Dielectric property of (TiO2)x−(Ta2O5)1−x thin films

J.-Y. Gan, Y. C. Chang, and T. B. Wu

Appl. Phys. Lett. 72, 332 (1998); http://dx.doi.org/10.1063/1.120746 (3 pages) | Cited 31 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
(TiO2)x−(Ta2O5)1−x thin films were prepared with radio-frequency magnetron sputtering deposition in this study. The dielectric constant measured from these films appears to critically depend on the amount of TiO2 incorporated into the film and post-anneal condition. The composition dependence was found similar to that reported on (TiO2)x−(Ta2O5)1−x bulk. The highest value of dielectric constant is about 55 for a TiO2 content of 8% and annealing at 800 °C. Compared to pure Ta2O5 thin films, significant enhancement in dielectric constant is obtained by adding small quantity of TiO2. © 1998 American Institute of Physics.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films
81.15.Cd Deposition by sputtering
77.22.Ch Permittivity (dielectric function)
61.66.Bi Elemental solids
61.66.Dk Alloys
81.40.Gh Other heat and thermomechanical treatments
81.40.Rs Electrical and magnetic properties related to treatment conditions
68.55.Nq Composition and phase identification
back to top
RSS Feeds

Modal and threshold analysis of dielectric-apertured vertical cavity surface emitting lasers

K. Y. Chang, J. Woodhead, and P. N. Robson

Appl. Phys. Lett. 72, 335 (1998); http://dx.doi.org/10.1063/1.120728 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The resonant wavelengths and mode radii of the dominant and certain higher order TEMmp modes supported by an oxide apertured vertical cavity surface emitting lasers are determined using a scalar variational formula. The reflectivity of the Bragg mirrors and the photon lifetime are calculated for each mode and both are found to decrease with decreasing oxide aperture diameter and increasing mode number. The aperture diameter, thickness, and axial position in the cavity, together with the refractive index contrast ratio used in the Bragg mirrors, are shown to be important in controlling the suppression of higher order modes. © 1998 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

The effect of growth interruption on the properties of InGaAs/InAlAs quantum well structures

W. C. H. Choy, P. J. Hughes, B. L. Weiss, E. H. Li, K. Hong, and D. Pavlidis

Appl. Phys. Lett. 72, 338 (1998); http://dx.doi.org/10.1063/1.120729 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of the growth interruption time during the growth of InGaAs/InAlAs quantum well structures is shown to have a significant effect on both the interband transitions, as determined by photoreflectance, and the electrical properties of the as-grown structure. The results show that, for increasing growth interruption time, the quantum well heterointerfaces become more abrupt and the carrier mobility increases, thereby demonstrating that long interruption times are preferable for the growth of high quality rectangular quantum well structures. © 1998 American Institute of Physics.
Show PACS
78.66.Fd III-V semiconductors
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.61.Ey III-V semiconductors
81.05.Ea III-V semiconductors
78.20.-e Optical properties of bulk materials and thin films
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Factors affecting resolution in scanning electron beam induced patterning of surface adsorption layers

Frank Y. C. Hui, Gyula Eres, and David C. Joy

Appl. Phys. Lett. 72, 341 (1998); http://dx.doi.org/10.1063/1.120730 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The monoatomic hydride layer on silicon was used as a prototype for resistless electron beam lithography. Arbitrary patterns with linewidths below 60 nm have been achieved. The variation of the linewidth with electron energy, electron dose, and substrate thickness was studied to determine the mechanisms that govern surface hydrogen desorption and subsequent pattern formation. Unlike in resist based lithography, no resolution enhancement was observed with decreasing substrate thickness. The experimental data in combination with Monte Carlo simulations of the backscattered and transmitted electrons suggest that surface hydrogen desorption and pattern formation are not strongly related to the backscattered electrons and the secondary electrons (energies <50 eV) associated with the backscattered electrons. © 1998 American Institute of Physics.
Show PACS
68.03.Fg Evaporation and condensation of liquids
68.43.Mn Adsorption kinetics
79.20.La Photon- and electron-stimulated desorption
85.40.Hp Lithography, masks and pattern transfer
79.20.Hx Electron impact: secondary emission
72.80.Cw Elemental semiconductors
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close