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16 Jan 1995

Volume 66, Issue 3, pp. 253-395

Page 2 of 2 Pages Previous Page | Jump to Page

Thickness‐field excited thickness‐shear resonators in (110) GaAs

Klas Hjort, Giorgio Schweeger, Alfons Dehé, Klaus Fricke, and Hans L. Hartnagel

Appl. Phys. Lett. 66, 326 (1995); http://dx.doi.org/10.1063/1.113533 (3 pages) | Cited 5 times

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The authors present experimental evidence for thickness‐field excitation of thickness‐shear vibrations in GaAs as an example material for zincblende‐crystal semiconductors. The resonance frequency is shown to agree perfectly with theory. This gives an alternative to the composite resonators in miniaturized local oscillators for, e.g., monolithic microwave integrated circuit applications. © 1995 American Institute of Physics.  
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77.65.-j Piezoelectricity and electromechanical effects
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
62.30.+d Mechanical and elastic waves; vibrations
43.38.Fx Piezoelectric and ferroelectric transducers

Highly reflective, long wavelength AlAsSb/GaAsSb distributed Bragg reflector grown by molecular beam epitaxy on InP substrates

O. Blum, I. J. Fritz, L. R. Dawson, A. J. Howard, T. J. Headley, J. F. Klem, and T. J. Drummond

Appl. Phys. Lett. 66, 329 (1995); http://dx.doi.org/10.1063/1.114202 (3 pages) | Cited 13 times

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Surface normal optoelectronic devices operating at long wavelengths (≳1.3 μm), require distributed Bragg reflectors (DBRs) with a practical number (≤50) of mirror layers. This requirement implies a large refractive index difference between the mirror layers, which is difficult to achieve in the traditionally used phosphide compounds. We demonstrate a highly reflective AlAsSb/GaAsSb DBR grown nominally lattice matched to an InP substrate by molecular beam epitaxy. Reflectivity measurements indicate a stop band centered at 1.74 μm with maximum reflectivity exceeding 98%, which is well fitted by our theoretical predictions. Atomic force microscopy and transmission electron microscopy indicate reasonable crystal quality with some defects due to an unintentional lattice mismatch to the substrate. © 1995 American Institute of Physics.
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42.79.Bh Lenses, prisms and mirrors
42.79.Fm Reflectors, beam splitters, and deflectors
78.66.Fd III-V semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

X‐ray crystal truncation rod scattering measurement of AsH3‐exposed InP/InPAs/InP single heterostructures

Yoshikazu Takeda, Yoshiyuki Sakuraba, Kei Fujibayashi, Masao Tabuchi, Takayuki Kumamoto, Isao Takahashi, Jimpei Harada, and Hidenori Kamei

Appl. Phys. Lett. 66, 332 (1995); http://dx.doi.org/10.1063/1.114203 (3 pages) | Cited 21 times

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The atomic‐level heterointerface structures of InP samples that contain growth interrupted and AsH3‐exposed surface, with 20 Å thick cap layer, were revealed by x‐ray crystal truncation rod scattering measurement. The As atom distribution, the thickness of the cap layer, and the tetragonal distortion of the lattices were obtained from the samples that have only single modified layer in the whole InP wafer. The calculated total amounts of As matched well with the value obtained by fluorescence x‐ray analysis. © 1995 American Institute of Physics.
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68.55.-a Thin film structure and morphology
68.35.Fx Diffusion; interface formation

Thermal dependence of the refractive index of GaAs and AlAs measured using semiconductor multilayer optical cavities

J. Talghader and J. S. Smith

Appl. Phys. Lett. 66, 335 (1995); http://dx.doi.org/10.1063/1.114204 (3 pages) | Cited 28 times

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The longitudinal optical mode shift with temperature was measured in two vertical cavity surface‐emitting laser (VCSEL) type optical resonators with different GaAs and AlAs layer structures. The measurements show distinct differences in the behavior of the cavities. From the data the thermal dependencies of the indices of refraction of GaAs and AlAs for wavelengths near 1 μm were determined to be (2.67±0.07)×10−4/°C and (1.43±0.07)×10−4/°C, respectively. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation
78.66.Fd III-V semiconductors

Bimodal roughness of heterointerface in quantum wells analyzed by photoluminescence excitation spectroscopy

J. C. Woo, S. J. Rhee, Y. M. Kim, H. S. Ko, W. S. Kim, and D. W. Kim

Appl. Phys. Lett. 66, 338 (1995); http://dx.doi.org/10.1063/1.114205 (3 pages) | Cited 8 times

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Photoluminescence excitation (PLE) studies were performed on GaAs‐Al0.25Ga0.75As quantum wells (QWs) with fractional monolayer differences. The quantized PLE peaks and their submonolayer shifts clearly show that the heterointerface of thin QWs prepared by growth‐interrupted molecular beam epitaxy has islands which extend out a lateral dimension larger than 100 Å, but they themselves have the microroughness smaller than 30 Å. The result of this work using exciton as the probe provides a clear evidence supporting the bimodal roughness model. © 1995 American Institute of Physics.
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68.55.-a Thin film structure and morphology
68.35.Fx Diffusion; interface formation
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

Observation of strong contrast from doping variations in transmission electron microscopy of InP‐based semiconductor laser diodes

R. Hull, F. A. Stevie, and D. Bahnck

Appl. Phys. Lett. 66, 341 (1995); http://dx.doi.org/10.1063/1.114206 (3 pages) | Cited 5 times

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We report strong transmission electron microscope (TEM) contrast between p‐, i‐, and n‐doped InP layers in semiconductor laser diodes. For doping concentrations ∼1018 cm−3, contrast levels on the order 30% are observed between p‐ and n‐type layers. A critical feature of these experiments is that the samples imaged in the TEM are relatively perfect, plane‐parallel sided membranes fabricated with a focused ion beam. This technique offers the ability to detect and map doping variations with nm‐scale resolution, simultaneously with the other compositional and defect information inherent to TEM. © 1995 American Institute of Physics.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.uj III-V and II-VI semiconductors
42.55.Px Semiconductor lasers; laser diodes

Quantitative two‐dimensional dopant profile measurement and inverse modeling by scanning capacitance microscopy

Y. Huang, C. C. Williams, and J. Slinkman

Appl. Phys. Lett. 66, 344 (1995); http://dx.doi.org/10.1063/1.114207 (3 pages) | Cited 40 times

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Quantitative dopant profile measurements are performed on a nanometer scale by scanning capacitance microscopy (SCM). An atomic force microscope is used to position a nanometer scale tip at a semiconductor surface, and local capacitance change is measured as a function of sample bias. A new feedback method has been demonstrated in which the magnitude of the ac bias voltage applied to the sample is adjusted to maintain a constant capacitance change as the tip is scanned across the sample surface. A quasi‐1D model is used to extract dopant density profiles from the SCM measurements. The inverted SCM dopant profiles are compared with profiles obtained by process simulation and secondary ion mass spectroscopy measurement. Good agreement was found between the SCM measured profile and the lateral profile predicted by SUPREM 4 over the concentration range from 1017 to 1020 cm−3. © 1995 American Institute of Physics.
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61.72.S- Impurities in crystals
61.72.uf Ge and Si
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

A new InP‐based heterojunction bipolar transistor utilizing an In0.53Al0.22Ga0.25As base

Y. H. Wu, J. S. Su, W. C. Hsu, W. C. Liu, and W. Lin

Appl. Phys. Lett. 66, 347 (1995); http://dx.doi.org/10.1063/1.114208 (2 pages)

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A lattice‐matched In0.53Al0.22Ga0.25As/InP heterojunction bipolar transistor has been fabricated by low‐pressure metalorganic chemical vapor deposition (LP‐MOCVD). No potential spike due to zero conduction band discontinuity at the emitter‐base heterojunction is obtained. Meanwhile, the larger valence discontinuity (ΔEV=460 meV) than AlGaAs/GaAs and InGaAs/InP systems provides this structure with a better hole confinement. An offset voltage as low as 50 mV along with a current gain of 85 is achieved. © 1995 American Institute of Physics.
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85.30.Pq Bipolar transistors

Photoconduction in porous TiO2 sensitized by PbS quantum dots

P. Hoyer and R. Könenkamp

Appl. Phys. Lett. 66, 349 (1995); http://dx.doi.org/10.1063/1.114209 (3 pages) | Cited 79 times

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Photoconduction in heterogeneous thin films consisting of a porous nanocrystalline TiO2 matrix and internally adsorbed quantum size PbS clusters is reported. The TiO2 serves to establish electrical contact to the PbS clusters, and the PbS cluster size is chosen so that photogenerated excess electrons are directly injected from the PbS to the TiO2. The films exhibit strong photoconductance in the visible region, indicating photoelectric sensitization of the TiO2 by the PbS clusters. Comparison of the absorption and photocurrent spectra shows that only PbS clusters of sizes smaller than ∼25 Å contribute to the sensitization. For larger clusters the band alignment at the TiO2/PbS interface appears to be unfavorable for carrier transfer. Further improvement in the photoresponse will have to involve optimization of the transport properties in the nanocrystalline TiO2. © 1995 American Institute of Physics.
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73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.50.Pz Photoconduction and photovoltaic effects
81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices

Comparison of triethylaluminum, triethylgallium, triethylindium, and triethylantimony on GaAs(100)

John M. Heitzinger, M. S. Jackson, and J. G. Ekerdt

Appl. Phys. Lett. 66, 352 (1995); http://dx.doi.org/10.1063/1.114210 (3 pages) | Cited 6 times

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The surface chemistry of triethylaluminum, triethylgallium, triethylindium, and triethylantimony was studied on GaAs(100) using thermal desorption spectroscopy, static secondary ion mass spectroscopy, and x‐ray photoelectron spectroscopy. Ethylene, the major hydrocarbon reaction product, desorbs from the GaAs(100) surface during thermal desorption spectroscopy experiments at 565 K for all four molecules. This indicates an identical rate limiting step for the elimination of ethyl groups from the surface following adsorption of these molecules. We propose that ethyl groups migrate to Ga sites and then undergo reaction at these sites. © 1995 American Institute of Physics.
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82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Diffusion of implanted Be in AlxGa1−xAs as a function of Al concentration and anneal temperature

Cynthia C. Lee, Michael D. Deal, and John C. Bravman

Appl. Phys. Lett. 66, 355 (1995); http://dx.doi.org/10.1063/1.114211 (3 pages) | Cited 5 times

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Diffusion of ion implanted Be in AlxGa1−xAs was studied as a function of Al concentration and annealing temperature and was compared to diffusion in GaAs. The behavior of Be in AlxGa1−xAs is similar to that in GaAs, even showing the anomalous behavior of increasing redistribution with decreasing temperature. The diffusivity of Be appears to increase with Al content which may be due to increasing bonding strength of matrix atoms with the addition of Al, preventing the easy transferral of Be from interstitial to substitutional sites. The oversaturation of Be interstitials may also explain the persistence of anomalous diffusion behavior in AlxGa1−xAs with respect to anneal temperature. This is discussed in terms of the substitutional‐interstitial diffusion mechanism, the relative amount of interstitial and substitutional Be, and the relative difficulty of moving from an interstitial to a substitutional site. © 1995 American Institute of Physics.
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61.72.uj III-V and II-VI semiconductors
61.72.Cc Kinetics of defect formation and annealing
66.30.J- Diffusion of impurities

Photodegradation of CdxZn1−xSe quantum wells

G. M. Haugen, S. Guha, H. Cheng, J. M. DePuydt, M. A. Haase, G. E. Höfler, J. Qiu, and B. J. Wu

Appl. Phys. Lett. 66, 358 (1995); http://dx.doi.org/10.1063/1.114212 (3 pages) | Cited 27 times

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Photoluminescence imaging was used to study photodegradation in CdZnSe quantum wells, important to II‐VI based blue‐green light emitter technology. The observed degradation microstructure evolves similarly to features observed during CdZnSe based LED and laser operation. Degradation is shown to emanate from pre‐existing defects to form dark line defects along the 〈100〉 directions. We report an observation of a mobile defect in II‐VI materials that is the precursor to the 〈100〉 dark line defects.
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78.66.Hf II-VI semiconductors
78.55.Et II-VI semiconductors
42.55.Px Semiconductor lasers; laser diodes
85.60.Jb Light-emitting devices

Nanoscale InP islands embedded in InGaP

A. Kurtenbach, K. Eberl, and T. Shitara

Appl. Phys. Lett. 66, 361 (1995); http://dx.doi.org/10.1063/1.114213 (3 pages) | Cited 73 times

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We have prepared small InP islands which are embedded in In0.485Ga0.515P grown on a (100) GaAs substrate by solid‐source molecular beam epitaxy. The InP islands form due to the 3.7% lattice mismatch between In0.485Ga0.515P and InP. Atomic force microscopy measurements show that the island size is typically ∼50 nm in diameter and ∼5 nm in height for nominally two monolayers of InP deposited on In0.485Ga0.515P. The energy of the photoluminescence (PL) peak shifts from 1.85 to 1.53 eV as the nominal InP thickness increases from 2 to 10 monolayers. A minimum PL linewidth of 21.6 meV and the maximum intensity of the PL originating from the InP islands is observed for 7.3 monolayers InP. © 1995 American Institute of Physics.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices
78.55.Cr III-V semiconductors

Magnetophotoluminescence of biaxially compressed InAsSb quantum wells

S. R. Kurtz and R. M. Biefeld

Appl. Phys. Lett. 66, 364 (1995); http://dx.doi.org/10.1063/1.114214 (3 pages) | Cited 26 times

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Heterostructures with biaxially compressed InAsSb are being considered as active regions for midwave infrared diode lasers. Quantum wells of biaxially compressed InAs1−xSbx (x≊0.09) in unstrained InAs were characterized using magnetophotoluminescence. The quantum size shift of the photoluminescence for a series of quantum wells produced an estimate of the conduction band offset. In magnetic field studies, the holes in the strained quantum wells exhibited a decrease in effective mass, approaching that of the electrons. A type I band offset was observed for these InAsSb/InAs heterostructures. Throughout this study, magnetoexcitonic behavior is observed; our analysis indicates that the exciton binding energy increases with quantum confinement. © 1995 American Institute of Physics.  
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78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

TMGa /TEGa interactions in metalorganic molecular beam epitaxy

M. Kamp, G. Mörsch, H. Lüth, and V. Frese

Appl. Phys. Lett. 66, 367 (1995); http://dx.doi.org/10.1063/1.114215 (3 pages)

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Using TMGa and TEGa simultaneously for the metalorganic molecular beam epitaxy growth of GaAs, interactions between the precursors have been observed. Whereas the resulting growth rate is unaffected, the obtained carrier concentrations reveal deviations up to 85% from the superpositioned values. Separate and common injection of both group III alkyls have been investigated. From these, interactions within the common group III injector, if they take place at all, are found to be negligible compared to interactions on the surface. © 1995 American Institute of Physics.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
71.55.Eq III-V semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Phase locking a 3 mm waveband Gunn oscillator with a high Tc superconducting Josephson junction at 77 K

Huabing Wang, Weiwei Xu, Qiheng Cheng, Zhengming Ji, Ruizhang Gao, Peiheng Wu, and Zhicai Xu

Appl. Phys. Lett. 66, 370 (1995); http://dx.doi.org/10.1063/1.114216 (3 pages) | Cited 6 times

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Using a high‐temperature superconducting YBa2Cu3O7−δ Josephson‐junction harmonic mixer operated at 77 K and an analog phase‐locking loop, we have locked a 3 mm waveband Gunn oscillator to a synthesizer for harmonic numbers ranging from 10 to 52. The spectrum of the phase‐locked intermediate frequency reveals good phase‐locked quality even for the 48th harmonic mixing between the signal at 104.3 GHz and the local oscillator at about 2 GHz. Our experimental results show that a high Tc superconducting harmonic mixer can work efficiently with high harmonic number for phase locking in the millimeter waveband. © 1995 American Institute of Physics.  
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85.25.Cp Josephson devices
84.30.Qi Modulators and demodulators; discriminators, comparators, mixers, limiters, and compressors
74.50.+r Tunneling phenomena; Josephson effects

Low noise YBa2Cu3O7−x–SrTiO3–YBa2Cu3O7−x multilayers for improved superconducting magnetometers

F. Ludwig, D. Koelle, E. Dantsker, D. T. Nemeth, A. H. Miklich, John Clarke, and R. E. Thomson

Appl. Phys. Lett. 66, 373 (1995); http://dx.doi.org/10.1063/1.114217 (3 pages) | Cited 28 times

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We have fabricated YBa2Cu3O7−x–SrTiO3–YBa2Cu3O7−x (YBCO–STO–YBCO) trilayers, in which each layer is patterned photolithographically, capping the first YBCO film with an in situ STO film. Atomic force microscopy demonstrates that the capping process dramatically improves the quality of the surface of the second layer, allowing the growth of an upper YBCO film with a substantially reduced level of low‐frequency flux noise. A magnetometer with a multiturn flux transformer coupled to a dc superconducting quantum interference device achieved a magnetic field noise of 74 fT Hz−1/2 at 1 Hz, improving to 31 fT Hz−1/2 at 1 kHz. © 1995 American Institute of Physics.
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85.25.Dq Superconducting quantum interference devices (SQUIDs)
74.78.-w Superconducting films and low-dimensional structures
74.78.Fk Multilayers, superlattices, heterostructures

Use of super Schottky diodes in a cryogenic radio frequency superconducting quantum interference device readout

M. Mück, Th. Becker, and C. Heiden

Appl. Phys. Lett. 66, 376 (1995); http://dx.doi.org/10.1063/1.114218 (3 pages)

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We describe the fabrication and characterization of super Schottky diodes which are used in the cryogenic part of a 3 GHz radio frequency superconducting quantum interference device (rf SQUID) readout electronics. The diodes were prepared on silicon wafers with an n‐doping level of 5×1024 m−3. They exhibited sensitivities of 1500 V−1 at 4.2 K, and a noise equivalent power of 2×10−15 W/√Hz was measured at 2.1 GHz. Using planar niobium 3 GHz rf SQUIDs and a cooled rf amplifier, experiments have been performed to investigate the feasibility of these super Schottky diodes for demodulation of the SQUID rf signal voltage. A simple cryogenic rf SQUID readout, employing two transistors and one super Schottky diode is described and investigated. Flux noise measurements in an open loop have been performed using this readout. © 1995 American Institute of Physics.
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85.25.Dq Superconducting quantum interference devices (SQUIDs)

Demagnetization of porous compacts of iron‐alloy powder under shock compression

Hideaki Oda, Takashi Sato, and Ken‐ichi Kondo

Appl. Phys. Lett. 66, 379 (1995); http://dx.doi.org/10.1063/1.114219 (3 pages)

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Demagnetization of porous green compacts consisting of iron‐alloy powder was observed under shock compression in the range of 4.0–13.5 GPa and 660–2040 K. The total reduction of the initial magnetization occurs under shock conditions with pressures exceeding 9 GPa and a temperature of 1300 K, and the possible mechanism for the observed demagnetization is consistent with the whole and/or partial α‐ to γ‐phase transition in the powder, depending on the localization of heat at the particle surfaces. The mechanism is also consistent with the anomalous low value of residual magnetic flux density of the recovered material which was overcompacted under undesirable conditions. © 1995 American Institute of Physics.
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75.50.Bb Fe and its alloys
81.20.Ev Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
81.40.Rs Electrical and magnetic properties related to treatment conditions

Large magnetoresistance in polycrystalline La–Y–Ca–Mn–O

S. Jin, H. M. O’Bryan, T. H. Tiefel, M. McCormack, and W. W. Rhodes

Appl. Phys. Lett. 66, 382 (1995); http://dx.doi.org/10.1063/1.114220 (3 pages) | Cited 195 times

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A large magnetoresistance ratio in excess of 10 000% (at 140 K, H=6 T) has been obtained in a sintered perovskitelike material with a composition of La0.60Y0.07Ca0.33MnOx. The doping of La–Ca–Mn–O with Y resulted in a decrease in the lattice parameter by ∼0.2%, and improved the magnetoresistance by an order of magnitude. The fact that such a large magnetoresistance can be obtained in a polycrystalline material implies that an epitaxial film growth may not be necessary for device applications, with fewer restrictions in substrate selection and processing parameters. Low field measurements at 77 K gave a magnetoresistance ratio of ∼6.5% at H=500 Oe in the La–Y–Ca–Mn–O sample. © 1995 American Institute of Physics.
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72.20.My Galvanomagnetic and other magnetotransport effects
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects

Superparamagnetic Fe clusters in Ag matrix produced by sputter‐gas aggregation

G.‐F. Hohl, T. Hihara, M. Sakurai, T. J. Konno, K. Sumiyama, F. Hensel, and K. Suzuki

Appl. Phys. Lett. 66, 385 (1995); http://dx.doi.org/10.1063/1.114221 (3 pages) | Cited 9 times

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Experiments to generate a thin composite Fe‐Ag film employing a sputter‐gas‐aggregation process are described. The magnetic properties are studied at low temperatures. In addition, the morphology is determined by high‐resolution transmission electron microscopy and the structure by using x‐ray diffraction and XAFS. Small clusters of about 11 Å in diameter are highly dispersed in an Ag matrix. They show the characteristics of interacting superparamagnets. © 1995 American Institute of Physics.  
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75.50.Tt Fine-particle systems; nanocrystalline materials

Magnetic properties and magnetostriction in TbFe2 compound with the addition of manganese or gallium

Y. J. Tang, H. L. Luo, N. F. Gao, Y. Y. Liu, and S. M. Pan

Appl. Phys. Lett. 66, 388 (1995); http://dx.doi.org/10.1063/1.114197 (3 pages) | Cited 10 times

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In the present study magnetic and magnetostrictive properties of Tb(Fe1−xTx)2 (T=Mn, Ga) compounds were examined by magnetic measurement, Mössbauer, and x‐ray study. Mössbauer study shows that the easy magnetization direction of the compounds may deviate slightly from the major axis of symmetry and the average isomer shift of the compounds decreases with increasing the x value, which was attributed to the charge transfer from 3d electrons of Mn atoms or 4p electrons of Ga atoms into the 3d band of Fe. It was also found from x‐ray measurement that the spontaneous magnetostriction λ111 decreased due to Mn or Ga substitution, which can be understood on the basis of the single‐ion model. The increase of the polycrystal magnetostriction λs due to Mn substitution was also found and can be ascribed to the increase of λ100, which may be caused by the filling of d bands due to substitution. © 1995 American Institute of Physics.  
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75.80.+q Magnetomechanical effects, magnetostriction
75.30.Gw Magnetic anisotropy
75.50.Bb Fe and its alloys

Relationship between diamond growth rate and hydrocarbon injector location in direct‐current arcjet reactors

David S. Dandy and Michael E. Coltrin

Appl. Phys. Lett. 66, 391 (1995); http://dx.doi.org/10.1063/1.114198 (3 pages) | Cited 7 times

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A series of detailed calculations have been carried out using a stagnation flow model to examine the dependence of diamond growth rate on hydrocarbon injector location in dc arcjet reactors. It is predicted that, for methane feed, growth rate can be increased by as much as 75% by relocating the injector from a position near the plasma torch exit to one near the diamond surface, but outside the boundary layer. As the injector is moved towards the surface from the plasma torch, the concentrations of C and CH3 present at the surface increase. When the injector is located within the boundary layer, the lower atomic hydrogen concentration and short residence time leave most of the injected CH4 unreacted, causing growth rates to drop. © 1995 American Institute of Physics.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
52.77.Bn Etching and cleaning
52.77.Dq Plasma-based ion implantation and deposition
52.65.-y Plasma simulation
FREE

Comment on ‘‘Properties of YBa2Cu3O7−x/YBa2Cu2.79Co0.21O7−x/ YBa2Cu3O7−x edge junctions’’ [Appl. Phys. Lett. 63, 2420 (1993)]

A. W. Kleinsasser

Appl. Phys. Lett. 66, 394 (1995); http://dx.doi.org/10.1063/1.114199 (1 page) | Cited 3 times

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Abstract Unavailable
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74.50.+r Tunneling phenomena; Josephson effects
74.45.+c Proximity effects; Andreev reflection; SN and SNS junctions
74.78.-w Superconducting films and low-dimensional structures
FREE

Response to ‘‘Comment on ‘Properties of YBa2Cu3O7−x/ YBa2Cu2.79Co0.21O7−x/YBa2Cu3O7−x edge junctions’ ’’ [Appl. Phys. Lett. 66, 394 (1995)]

K. Char, L. Antognazza, and T. H. Geballe

Appl. Phys. Lett. 66, 395 (1995); http://dx.doi.org/10.1063/1.114200 (1 page) | Cited 2 times

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Abstract Unavailable
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74.50.+r Tunneling phenomena; Josephson effects
74.45.+c Proximity effects; Andreev reflection; SN and SNS junctions
74.78.-w Superconducting films and low-dimensional structures
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