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 Feb 1993

Volume 62, Issue 5, pp. 435-537

Page 2 of 2 Pages Previous Page | Jump to Page

Incorporation of high concentrations of erbium in crystal silicon

A. Polman, J. S. Custer, E. Snoeks, and G. N. van den Hoven

Appl. Phys. Lett. 62, 507 (1993); http://dx.doi.org/10.1063/1.108894 (3 pages) | Cited 60 times

Full Text: | Download PDF

Show Abstract
High concentrations (≊1020/cm3) of Er have been incorporated in crystal Si by solid phase epitaxy of Er‐implanted amorphous Si. This concentration is some 2 orders of magnitude higher than has previously been achieved. During thermal recrystallization of the amorphous layer, segregation and trapping of Er occurs at the moving crystal/amorphous interface. As long as the concentration of Er trapped in the crystal remains below a critical level, perfect epitaxial regrowth occurs. This concentration limit is temperature dependent, decreasing from 1.2±0.2×1020/cm3 at 600 °C to 6±2×1019/cm3 at 900 °C.
Show PACS
61.72.uf Ge and Si
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.15.Np Solid phase epitaxy; growth from solid phases
64.75.-g Phase equilibria

Epitaxial Si films on Ge(100) grown via H/Cl exchange

S. M. Gates, D. D. Koleske, J. R. Heath, and M. Copel

Appl. Phys. Lett. 62, 510 (1993); http://dx.doi.org/10.1063/1.108895 (3 pages) | Cited 16 times

Full Text: | Download PDF

Show Abstract
Thin Si films have been grown isothermally on Ge(100) substrates using alternating exposures of Si2H6 and Si2Cl6, maintaining chlorine and hydrogen surface termination. At 465 °C, film growth rate is roughly 2 monolayer per cycle (one cycle equals 1 Si2H6 and 1 Si2Cl6 exposure). At 475 °C a uniform epitaxial film is obtained, while islanding is observed at higher T. This process is thermally activated and is not strictly self‐limiting, but has certain desirable characteristics of atomic layer epitaxy growth.  
Show PACS
68.55.-a Thin film structure and morphology
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Focused‐ion‐beam defined and overgrown collector‐up AlGaAs/GaAs heterojunction bipolar transistors

T. Ishibashi, A. Fischer, A. D. Wieck, and K. Ploog

Appl. Phys. Lett. 62, 513 (1993); http://dx.doi.org/10.1063/1.108896 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
The focused‐ion‐beam technique combined with overgrowth of AlGaAs/GaAs heterostructures by molecular beam epitaxy has been successfully applied to injection current confinement in collector‐up heterojunction bipolar transistors. A potential barrier to block electron injection is produced by Ga focused‐ion‐beam implantation into n+‐GaAs subemitter layer and is embedded beneath the extrinsic emitter. The fabricated collector‐up transistors with intrinsic emitter dimensions of 20×20 μm and extrinsic emitter dimensions of 85×110 μm yield current gains of 30, demonstrating the effective current confinement in the proposed device structure.
Show PACS
85.30.Pq Bipolar transistors

Measurement of damage profile in semiconductors: A sensitive optical technique

C. Shwe and M. Gal

Appl. Phys. Lett. 62, 516 (1993); http://dx.doi.org/10.1063/1.108897 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
We have used differential reflectance spectroscopy in combination with chemical‐etch removal of surface layers to measure the depth profile of damage in GaAs. Damage was created by one of several ion‐assisted processes, including sputter etching, reactive‐ion etching, hydrogenation, and ion implantation. The sensitivity of this optical technique is shown to be comparable or greater than that obtained by other previous methods. From our measurements we estimate the lowest detectable damage level to be equivalent to damage created by 50 keV He+ ions at an ion dose of 1×108 ions/cm2. The depth resolution of this method is approximately 60 Å. Two examples of measured damage profiles are shown in this communication.  
Show PACS
61.80.Jh Ion radiation effects
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Band edge shifts of p‐type copper indium diselenide electrodes in aqueous electrolytes

Withana Siripala, Jacques Vedel, Daniel Lincot, and David Cahen

Appl. Phys. Lett. 62, 519 (1993); http://dx.doi.org/10.1063/1.108898 (3 pages) | Cited 6 times

Full Text: | Download PDF

Show Abstract
Impedance measurements were used to evaluate the relative band edge positions of single crystal p‐CuInSe2 electrodes in various aqueous electrolytes, by measuring the extrapolated flatband potentials, Vfb. We find that Vfb can be shifted, depending on the extent of the potential scan and on the pH of the electrolyte used, over a range of up to 1.7 V (between pH 0–pH 14). In the pH range 0–6, Vfb can be fixed at intermediate values, which, in their turn, are determined by the pH of the electrolyte.
Show PACS
73.30.+y Surface double layers, Schottky barriers, and work functions
82.45.-h Electrochemistry and electrophoresis
84.60.Jt Photoelectric conversion

Subpicosecond hot hole dynamics in highly excited GaAs

T. Gong, P. M. Fauchet, J. F. Young, and P. J. Kelly

Appl. Phys. Lett. 62, 522 (1993); http://dx.doi.org/10.1063/1.108899 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
The buildup of band‐edge gain is observed on a subpicosecond time scale in highly excited intrinsic GaAs. Using a kinetic model to fit the experimentally determined ‘‘gain time’’ at different wavelengths, the transient behavior of the optically injected hole temperature is determined. The data are not consistent with a simple decay of the hot hole temperature due to phonon emission processes. We show that a simple estimate of the energy transfer from electrons to holes via Coulomb scattering qualitatively accounts for the observed behavior of the hole temperature.
Show PACS
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
78.47.-p Spectroscopy of solid state dynamics
72.20.Dp General theory, scattering mechanisms

Comparison of electroabsorption in asymmetric triangular and rectangular GaAs/AlxGa1−xAs multiple quantum wells

D. S. Gerber, R. Droopad, and G. N. Maracas

Appl. Phys. Lett. 62, 525 (1993); http://dx.doi.org/10.1063/1.108900 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
We present the first detailed experimental comparison of electroabsorption in equivalent rectangular and asymmetric triangular multiple quantum wells. The absorption spectra are extracted from reflectance and transmittance measurements on molecular beam epitaxy‐grown samples. With absorption edges at the same photon energy, the asymmetric triangular quantum well is much wider than its rectangular well counterpart which reduces its absorption coefficient by approximately a factor of nine compared to the rectangular well, in agreement with theoretical estimates. Implications for electroabsorption modulator devices are discussed.
Show PACS
78.66.Fd III-V semiconductors
78.20.Jq Electro-optical effects

In situ growth of epitaxial YBa2Cu3O7 thin films by on‐axis unbalanced direct current magnetron sputtering

N. Savvides and A. Katsaros

Appl. Phys. Lett. 62, 528 (1993); http://dx.doi.org/10.1063/1.108901 (3 pages) | Cited 16 times

Full Text: | Download PDF

Show Abstract
Superconducting YBa2Cu3O7−x thin films are prepared in situ by on‐axis dc magnetron sputtering from a single stoichiometric target. The magnetron uses an unbalanced magnetic field configuration to eliminate resputtering effects, and high quality thin films on MgO (100) substrates are realized with excellent reproducibility. The target is sputtered in Ar/O2 mixture at a fixed partial pressure ratio pAr/pO2= 15:1. We report on the growth and properties of films deposited (a) as a function of the total sputtering pressure pt (1–100 Pa) at fixed substrate heater temperature Ts=740 °C, and (b) as a function of Ts (600–860 °C) at fixed pt=42 Pa. Epitaxial c‐axis thin films are obtained over a wide range of deposition conditions (Ts≥700 °C, pt≥30 Pa). These films have superconducting transition temperatures Tc=86–90 K, critical current densities Jc77≥106 A cm−2, and resistance ratios R300/R100=2.0–3.1.
Show PACS
81.15.Cd Deposition by sputtering
74.78.-w Superconducting films and low-dimensional structures
74.72.-h Cuprate superconductors

Vapor transport growth of C60 crystals

J. Z. Liu, J. W. Dykes, M. D. Lan, P. Klavins, R. N. Shelton, and M. M. Olmstead

Appl. Phys. Lett. 62, 531 (1993); http://dx.doi.org/10.1063/1.108902 (2 pages) | Cited 22 times

Full Text: | Download PDF

Show Abstract
A vapor transport technique has been used to produce large, high quality C60 single crystals. This technique, which uses an open tube method with a flowing helium gas carrier, eliminates the crystal size limitation found in the vacuum sublimation growth method.  
Show PACS
81.10.Bk Growth from vapor
81.10.Aj Theory and models of crystal growth; physics and chemistry of crystal growth, crystal morphology, and orientation

Proximity effect reduction using thin insulating layers

Kee Woo Rhee and Martin C. Peckerar

Appl. Phys. Lett. 62, 533 (1993); http://dx.doi.org/10.1063/1.108903 (2 pages)

Full Text: | Download PDF

Show Abstract
In this letter, we demonstrate a novel method for reducing or eliminating e‐beam proximity effect in patterning tungsten for use as an x‐ray mask absorber material. The method involves interposting a thin (200 nm) layer of low atomic weight insulating material (such as SiO2) between the resist and the underlying substrate. Examples are shown in which gratings of 0.2 μm lines with a 0.5 μm period were written without dose correction for proximity effect compensation.
Show PACS
85.40.Hp Lithography, masks and pattern transfer
79.20.Kz Other electron-impact emission phenomena
61.80.Fe Electron and positron radiation effects

Successive paraelectric‐antiferroelectric‐ferroelectric phase transitions in highly ordered perovskite lead ytterbium tantalate

Naohiko Yasuda and Junichi Konda

Appl. Phys. Lett. 62, 535 (1993); http://dx.doi.org/10.1063/1.109617 (3 pages) | Cited 28 times

Full Text: | Download PDF

Show Abstract
Dielectric properties such as the permittivity, dielectric loss tangent and spontaneous polarization of highly ordered perovskite Pb(Yb1/2Ta1/2)O3 (PYT) compound which were prepared through the wolframite phase oxide were investigated. A dielectric anomaly which is characterized by a slight dielectric dispersion was found at a temperature Tm (e.g., Tm; 177 and 183 °C at 1 and 100 kHz, respectively). At temperatures below Tm, polarization P‐electric field E hysteresis loops were observed, and then ferroelectricity in antiferroelectric ordered perovskite PYT was confirmed. Highly ordered PYT has two successive paraelectric‐antiferroelectric‐ferroelectric phase transitions, similar to highly ordered perovskite lead cobalt tungstate (PCW).
Show PACS
77.22.-d Dielectric properties of solids and liquids
77.80.-e Ferroelectricity and antiferroelectricity
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
Page 2 of 2 Pages Previous Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close