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25 Jul 1988

Volume 53, Issue 4, pp. 257-343

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Solvable optimized four‐wave mixing configuration with cubic photorefractive crystals

Baruch Fischer and Shimon Weiss

Appl. Phys. Lett. 53, 257 (1988); http://dx.doi.org/10.1063/1.100140 (3 pages) | Cited 5 times

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An analysis of an optimized configuration for phase conjugation and four‐wave mixing in cubic photorefractive crystals (such as GaAs and Bi12SiO20) is presented. We obtain an exact solution of the four‐wave mixing configuration, and find a wide range of self‐oscillation regime.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.20.Jq Electro-optical effects
42.30.Va Image forming and processing

Enhanced resistance to photorefraction and photovoltaic effect in Li‐rich LiNbO3:Mg crystals

Jin‐ke Wen, Liang Wang, Yan‐sheng Tang, and Hua‐fu Wang

Appl. Phys. Lett. 53, 260 (1988); http://dx.doi.org/10.1063/1.100591 (2 pages) | Cited 16 times

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We have found that in connection with photorefraction the Li‐rich LiNbo3:Mg (5 mol %) can withstand higher light intensities than the congruent LiNbO3:Mg (5 mol %) and that the improvement is due to the increased photoconductivity with little change in photovoltaic current.
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78.20.Jq Electro-optical effects
72.40.+w Photoconduction and photovoltaic effects

Grating structure in self‐pumping barium titanate by local erasure

P. S. Brody

Appl. Phys. Lett. 53, 262 (1988); http://dx.doi.org/10.1063/1.100141 (3 pages) | Cited 4 times

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A method of examining the photorefractive grating in a self‐pumping barium titanate crystal is described; in this method, photorefractive grating elements are sequentially erased using a fine pulsed beam of photocarrier‐generating light, while the resulting decrements in the phase‐conjugate output are recorded. The erase beam scans the crystal in raster fashion, producing a map of decrements in the phase‐conjugate output; these are interpreted as indicating the position of volume photorefractive grating elements that contribute to the phase‐conjugate output. The results show that important elements of grating structure do exist in the front region of the crystal where the pumping beam enters.
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78.20.Jq Electro-optical effects
42.79.Dj Gratings
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

GaAs/GaAlAs distributed Bragg reflector laser with a focused ion beam, low dose dopant implanted grating

M. C. Wu, M. M. Boenke, S. Wang, W. M. Clark, E. H. Stevens, and M. W. Utlaut

Appl. Phys. Lett. 53, 265 (1988); http://dx.doi.org/10.1063/1.100142 (3 pages) | Cited 4 times

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We report for the first time, the performance of a GaAs/GaAlAs distributed Bragg reflector (DBR) laser using a focused ion beam implanted grating (FIB‐DBR). Stripes of Si++ with a period of 2300 Å and a dose ∼1014 cm−2 are directly implanted into the passive large optical cavity layer to provide the distributed feedback. Surface‐emitting light from the second‐order grating is observed. Threshold current of 110 mA and single DBR mode operation from 20 to 40 °C are obtained. The wavelength tuning rate with temperature is 0.8 Å/°C. The coupling coefficient is estimated to be 15 cm−1. The results show that FIB technology is practical for distributed feedback and DBR lasers and optoelectronic integrated circuits.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Direct modulation of a Nd:YAG laser by combined side and end laser diode pumping

Josef Berger, Gary Harnagel, David F. Welch, Don R. Scifres, and William Streifer

Appl. Phys. Lett. 53, 268 (1988); http://dx.doi.org/10.1063/1.100143 (3 pages) | Cited 1 time

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A Nd:YAG laser was directly amplitude modulated by using a combination of pulsed side and cw end diode pumping. The scheme suppressed relaxation oscillations, reduced pulse delays, increased pulse energy, and avoided higher order transverse mode operation.
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42.60.Fc Modulation, tuning, and mode locking
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.By Design of specific laser systems
42.79.Hp Optical processors, correlators, and modulators

Spectral and dynamic characteristics of buried‐heterostructure single quantum well (Al,Ga)As lasers

P. L. Derry, T. R. Chen, Y. H. Zhuang, J. Paslaski, M. Mittelstein, K. Vahala, and A. Yariv

Appl. Phys. Lett. 53, 271 (1988); http://dx.doi.org/10.1063/1.100144 (3 pages) | Cited 2 times

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We demonstrate that, as predicted, (Al,Ga)As single quantum well (SQW) lasers have substantially narrower spectral linewidths than bulk double‐heterostructure lasers. We have observed a further major reduction (>3×) in the linewidth of these SQW lasers when the facet reflectivities are enhanced. This observation is explained theoretically on the basis of the very low losses in coated SQW lasers and the value of the spontaneous emission factor at low threshold currents. We also report on the modulation frequency response parameter of these SQW lasers.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Fc Modulation, tuning, and mode locking
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Pb1−xEuxS films prepared by hot wall epitaxy

A. Ishida, N. Nakahara, T. Okamura, Y. Sase, and H. Fujiyasu

Appl. Phys. Lett. 53, 274 (1988); http://dx.doi.org/10.1063/1.100592 (2 pages) | Cited 8 times

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Pb1−x EuxS films were prepared for the first time using hot wall epitaxy technique. X‐ray diffraction and optical transmission measurements were performed for the films. Films with energy gaps up to 0.9 eV (up to x=0.2) were obtained. Lattice constants of the films were very close to that of PbS as is expected from the small lattice mismatch between PbS and EuS. It was found that the energy band gap increases very rapidly with the EuS content up to x=0.05 (dEg/dx=5 eV).
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.-w Optical properties of specific thin films
68.55.-a Thin film structure and morphology
81.15.Jj Ion and electron beam-assisted deposition; ion plating

Structural and optical properties of GaAlInAs lattice matched to InP grown by low‐pressure metalorganic vapor phase epitaxy

J. I. Davies, A. C. Marshall, M. D. Scott, and R. J. M. Griffiths

Appl. Phys. Lett. 53, 276 (1988); http://dx.doi.org/10.1063/1.100593 (3 pages) | Cited 10 times

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We report for the first time, the metalorganic vapor phase epitaxy (MOVPE) growth of the quaternary alloy GaxAlyIn1−x−yAs, lattice matched to InP. Single epitaxial layers were prepared showing specular morphologies and lattice matching within Δa/a=10−3. Epilayers showed a high degree of crystallinity with routine x‐ray linewidths of 20–40 seconds of arc. The lowest linewidth achieved was 22 seconds of arc. Room temperature and 4 K photoluminescence (PL) studies demonstrated very narrow excitonic transitions with ΔE at 4 K down to 5.4 meV. Band‐gap energies, obtained from the absorption edge and PL peak energies, plotted against Al composition showed that the alloy was best described by a straight line relationship between the ternary end points, Ga0.47In0.53As and Al0.48In0.52As with no bowing observed.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
78.55.Cr III-V semiconductors
68.55.-a Thin film structure and morphology

660 nm In0.5Ga0.5P light‐emitting diodes on Si substrates

Susumu Kondo, Shin‐ichi Matsumoto, and Haruo Nagai

Appl. Phys. Lett. 53, 279 (1988); http://dx.doi.org/10.1063/1.100150 (3 pages) | Cited 8 times

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In0.5Ga0.5P light‐emitting diodes (LED’s) that operate in the 660 nm region were fabricated on Si substrates using GaAs buffer layers. InGaP layers were grown by metalorganic‐chloride vapor phase epitaxy (MO‐chloride VPE), and GaAs layers were grown by metalorganic vapor phase epitaxy (MOVPE) at atmospheric pressure. Red color emission was clearly seen under room light at 20 mA dc injection. The LED operation was stable at 5 kA/cm2 despite the high dislocation density of around 107 cm−2 .
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85.60.Jb Light-emitting devices
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Charge distribution in GaAs‐Ga1−xAlxAs heterostructures under an external magnetic field

J. O. Sofo, C. R. Proetto, and C. A. Balseiro

Appl. Phys. Lett. 53, 282 (1988); http://dx.doi.org/10.1063/1.100151 (3 pages)

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We study the charge distribution in GaAs‐Ga1−xAlxAs heterostructures under an external magnetic field perpendicular to the interfaces. We obtain the charge‐density profile by solving in a self‐consistent way the Poisson and Schrödinger equations. Our results show that in a quantum well of Ga1−xAlxAs‐GaAs‐Ga1−xAlxAs with widths ranging between 70 and 110 Å the charge accumulation is a strongly dependent function of the well width and the external magnetic field.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.61.Ey III-V semiconductors

Photoluminescence from the two‐dimensional electron gas at GaAs/AlGaAs single heterojunctions

C. H. Yang, S. A. Lyon, and C. W. Tu

Appl. Phys. Lett. 53, 285 (1988); http://dx.doi.org/10.1063/1.99915 (3 pages) | Cited 13 times

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We have studied photoluminescence from GaAs/Al0.3Ga0.7 As modulation‐doped single heterojunctions, using excitation sources from infrared to ultraviolet near‐liquid‐helium temperature. The spectra have a strong interface component, accompanied by bulk GaAs and AlGaAs band‐gap luminescence. Using ultraviolet instead of infrared as the excitation, the interface signal is greatly enhanced relative to the bulk GaAs luminescence. The interface signal can be shifted to the higher energies when a semitransparent front gate is positively biased. Our observations indicate that the interface luminescence comes from the recombination of the two‐dimensional electrons with holes trapped at or near the interface. The peaks and the shoulders in the interface spectra appear to correspond to subbands of the two‐dimensional electron gas at the interface. Our results demonstrate the feasibility of doing spectroscopic studies on high‐mobility electrons at single heterojunctions.
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78.55.Cr III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
85.30.Tv Field effect devices
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

Reflection mass spectrometry of As incorporation during GaAs molecular beam epitaxy

J. Y. Tsao, T. M. Brennan, and B. E. Hammons

Appl. Phys. Lett. 53, 288 (1988); http://dx.doi.org/10.1063/1.99916 (3 pages) | Cited 20 times

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An apertured and cryoshrouded mass spectrometer, which measures line‐of‐sight molecular fluxes from the surface, has been incorporated into a GaAs molecular beam epitaxy system. The spectrometer is simple to implement, yet is a powerful real‐time growth diagnostic. We have used the spectrometer to measure transient and steady‐state As incorporation from As4 during bilayer‐by‐bilayer growth of GaAs. We find, interestingly, that (1) the incorporation coefficient does not oscillate significantly; (2) transient incorporation coefficients depend on surface reconstruction, and may be higher than 0.5 at high Ga fluxes; and (3) in the absence of a Ga flux, excess Ga on the surface need not imply an incorporation coefficient of 0.5.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
07.75.+h Mass spectrometers
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Photoconductance measurements on InAs0.22Sb0.78/GaAs grown using molecular beam epitaxy

C. G. Bethea, B. F. Levine, M. Y. Yen, and A. Y. Cho

Appl. Phys. Lett. 53, 291 (1988); http://dx.doi.org/10.1063/1.100594 (2 pages) | Cited 17 times

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We report the molecular beam epitaxial growth of InAs0.22Sb0.78 on semi‐insulating GaAs substrates, and the fabrication and characterization of photoconductance detectors.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
85.60.Gz Photodetectors (including infrared and CCD detectors)
73.50.Pz Photoconduction and photovoltaic effects
73.61.Ey III-V semiconductors

Diffusion of atomic silicon in gallium arsenide

E. F. Schubert, J. B. Stark, T. H. Chiu, and B. Tell

Appl. Phys. Lett. 53, 293 (1988); http://dx.doi.org/10.1063/1.99917 (3 pages) | Cited 49 times

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Silicon impurities with an initial Dirac‐delta‐function‐like distribution profile are diffused into GaAs using rapid thermal annealing. The diffusion of atomic Si is determined by a novel method of comparing experimental capacitance‐voltage profiles with a corresponding self‐consistent profile calculation. Capacitance‐voltage profiles broaden from 30 to 137 Å upon rapid thermal annealing at 1000 °C for 5 s. The diffusion coefficient and the activation energy of atomic Si diffusion in GaAs are determined to be D0=4×10−4 cm2/s and Ea=2.45 eV, respectively. The diffusion coefficient is two orders of magnitude smaller as compared to Si‐pair diffusion in GaAs.
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66.30.J- Diffusion of impurities
66.30.Dn Theory of diffusion and ionic conduction in solids
85.30.Hi Surface barrier, boundary, and point contact devices
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

High‐detectivity D∗=1.0×1010 cm √Hz/W GaAs/AlGaAs multiquantum well λ=8.3 μm infrared detector

B. F. Levine, C. G. Bethea, G. Hasnain, J. Walker, and R. J. Malik

Appl. Phys. Lett. 53, 296 (1988); http://dx.doi.org/10.1063/1.99918 (3 pages) | Cited 122 times

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We report the first high‐detectivity (D∗=1.0×1010 cm (Hz)1/2/W), high‐responsivity (Rv =30 000 V/W) GaAs/AlxGa1−xAs multiquantum well detector, sensitive in the long‐wavelength infrared band at λ=8.3 μm (operating at a temperature of T= 77 K). Because of the mature GaAs growth and processing technologies as well as the potential for monolithic integration with high‐speed GaAs field‐effect transistors, large focal plane arrays of these detectors should be possible.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.50.Pz Photoconduction and photovoltaic effects

Short‐period (AlAs)(GaAs) superlattice lasers grown by molecular beam epitaxy

P. Blood, E. D. Fletcher, and C. T. Foxon

Appl. Phys. Lett. 53, 299 (1988); http://dx.doi.org/10.1063/1.99901 (3 pages) | Cited 3 times

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We have used short‐period all‐binary (AlAs)(GaAs) superlattices with layers as thin as three monolayers to synthesize the barrier and cladding regions of GaAs quantum well lasers grown by molecular beam epitaxy. By studying the threshold current of single‐ and double‐well devices as a function of cavity length and temperature, we conclude that the optical scattering losses are very low, that the gain‐current characteristics are similar to alloy barrier devices, and that there is evidence for current leakage by recombination in the barriers.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Optical measurement of surface recombination in InGaAs quantum well mesa structures

K. Tai, T. R. Hayes, S. L. McCall, and W. T. Tsang

Appl. Phys. Lett. 53, 302 (1988); http://dx.doi.org/10.1063/1.99902 (2 pages) | Cited 30 times

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Surface recombination of optically created electron‐hole plasma in InGaAs/InP quantum well mesa structures formed by chemical beam epitaxy followed by anisotropic plasma etching is observed optically by a picosecond pump‐probe method. The exponential carrier lifetime in 3.3‐μm‐diam structures is reduced from 31 ns as measured for large diameters to 5.5 ns. We ascribe this reduction to a surface recombination velocity of 1.2×104 cm/s. The surface recombination velocity is about two orders of magnitude smaller than those reported for bulk GaAs layers exposed to air.
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73.25.+i Surface conductivity and carrier phenomena
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths

High quality InP layers grown by organometallic vapor phase epitaxy using tertiarybutylphosphine and phosphine

R. R. Saxena, J. E. Fouquet, V. M. Sardi, and R. L. Moon

Appl. Phys. Lett. 53, 304 (1988); http://dx.doi.org/10.1063/1.99903 (3 pages) | Cited 19 times

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A systematic study compares the quality of InP epitaxial layers grown by low‐pressure organometallic vapor phase epitaxy (OMVPE) using triethylindium, phosphine, and tertiarybutylphosphine (TBP) sources. High quality InP layers are obtained with either phosphorus source for growth at a high V/III ratio. The full widths at half‐maximum (FWHM) of the main 4 K photoluminescence peak from InP layers grown with phosphine and TBP sources are 1.1 and 1.3 meV, respectively. This 1.3 meV FWHM is the narrowest reported for InP grown by OMVPE with a nonhydride phosphorus source. High quality InP layers can be grown at a lower V/III ratio with the TBP source than with the phosphine source.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.-a Thin film structure and morphology

Constant‐current‐density model for the anomalous Hall effects in Hg0.8Cd0.2Te

D. S. Pan, Y. Lu, and M. Chu

Appl. Phys. Lett. 53, 307 (1988); http://dx.doi.org/10.1063/1.100595 (3 pages) | Cited 8 times

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This letter presents a simple model developed for calculating the Hall coefficient and Hall mobility in inhomogeneous narrow‐band‐gap semiconductors, including inclusions with opposite conduction type. The model is based on one assumption that the current density is a uniform constant in the sample in spite of the inhomogeneities. This assumption is supported by a variational calculation based on the principle of least entropy production rate. The model is then applied to explain the anomalous Hall data in the n‐type Hg0.8Cd0.2Te, and a good fit is obtained when p‐type Hg0.8Cd0.2Te is considered to be the inclusions. The results show that some assumptions in a previous layer model are not necessary in order to explain the observed phenomena. By using this simplified treatment of material inhomogeneity, it will be easier to design experiments to investigate the cause of such inhomogeneity.
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72.20.My Galvanomagnetic and other magnetotransport effects
72.20.Fr Low-field transport and mobility; piezoresistance
72.80.Ey III-V and II-VI semiconductors

Structure of nonrectangular HgCdTe superlattices grown by laser molecular beam epitaxy

J. T. Cheung, E.‐H. Cirlin, and N. Otsuka

Appl. Phys. Lett. 53, 310 (1988); http://dx.doi.org/10.1063/1.99904 (3 pages) | Cited 9 times

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Laser molecular beam epitaxy offers instantaneous and accurate composition and thickness control that was used successfully to grow HgCdTe‐based superlattice structures with rectangular, trapezoidal, triangular, and sawtooth‐shaped quantum wells. Their structures were characterized with cross‐sectional transmission electron microscopy and low‐temperature Auger depth profiling.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.-a Thin film structure and morphology
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

High‐speed planar GaAs photoconductors with surface implant layers

Gordon Wood Anderson, Nicolas A. Papanicolaou, Phillip E. Thompson, John B. Boos, Thomas F. Carruthers, David I Ma, Ingham A. G. Mack, John A. Modolo, and Francis J. Kub

Appl. Phys. Lett. 53, 313 (1988); http://dx.doi.org/10.1063/1.99905 (3 pages)

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Selective implantation of silicon into GaAs is demonstrated as a simple method for modifying the response characteristics of low‐doped planar GaAs photoconductors for optoelectronic circuits with varying requirements. Response times and sensitivities of the photoconductors were strongly dependent on the implantation dose and energy. Rise times and full width at half‐maximum (FWHM) values of devices receiving low‐dose implants were of the order of 40–150 ps. Rise times and FWHM values of devices which received higher dose implants were in the ranges 50–140 ps and 1–5 ns, respectively. The sensitivity of devices which received higher dose implants was about a factor of 100 (20 dB in optical power) greater than that of devices which received lower dose implants.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
61.72.U- Doping and impurity implantation

Advanced lift‐off planarization process for Josephson integrated circuits

Ichiro Ishida, Syuichi Tahara, and Yoshifusa Wada

Appl. Phys. Lett. 53, 316 (1988); http://dx.doi.org/10.1063/1.99906 (3 pages) | Cited 1 time

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An advanced lift‐off planarization process utilizing an undercut technique of a photoresist etching mask has been developed to achieve planarization of thin‐sputtered and fine‐patterned films that are necessary for high‐performance Josephson integrated circuits (IC’s). A stack of the same kind of photoresist layers, including the modified layer between them, has been utilized as an etching mask providing fine‐patterned film profiles with minimized resist degradation by the top photoresist protection layer. This advanced planarization process brings about smooth surfaces having no residues and no grooves along pattern edges. 30 nm deviation from planarity has been demonstrated on a 200‐nm‐thick planarized Nb superconducting layer. A four‐level interconnection of Josephson IC’s was successfully fabricated by this process.
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85.25.Cp Josephson devices
85.40.Hp Lithography, masks and pattern transfer
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology
85.40.Ls Metallization, contacts, interconnects; device isolation

Persistent currents in Tl‐Ba‐Ca‐Cu‐O superconductors

G. S. Grader, E. M. Gyorgy, L. G. Van Uitert, W. H. Grodkiewicz, T. R. Kyle, and M. Eibschutz

Appl. Phys. Lett. 53, 319 (1988); http://dx.doi.org/10.1063/1.100596 (2 pages) | Cited 4 times

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We have demonstrated the presence of circulating circumferential currents in toroids of Tl‐Ba‐Ca‐Cu‐O superconductors at 77.3 and 90.2 K. The nominal composition was Tl1.5Ba2Ca2Cu3Ox; however, both the x‐ray diffraction pattern and the Meissner effect indicate the presence of more than one phase. The circulating current was found to decrease by 27% in 3.8×103 s. The nature of the above time dependence is not consistent with the presence of a simple ohmic resistance but rather indicates that a process such as flux creep is the cause of this decay. An estimated upper limit of the resistivity is 1.3×10−14 Ω cm at 77.3 K.
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74.25.Ha Magnetic properties including vortex structures and related phenomena
74.70.-b Superconducting materials other than cuprates
74.25.Sv Critical currents
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition

Superconducting thin films of Bi‐Sr‐Ca‐Cu‐O obtained by laser ablation processing

B. F. Kim, J. Bohandy, T. E. Phillips, W. J. Green, E. Agostinelli, F. J. Adrian, K. Moorjani, L. J. Swartzendruber, R. D. Shull, L. H. Bennett, and J. S. Wallace

Appl. Phys. Lett. 53, 321 (1988); http://dx.doi.org/10.1063/1.100597 (3 pages) | Cited 17 times

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Thin films of Bi‐Sr‐Ca‐Cu‐O, deposited on (100) cubic zirconia by laser ablation from a bulk superconducting target of nominal composition BiSrCaCu2 Ox , have been investigated by dc resistance and magnetically modulated microwave absorption measurements. The latter technique reveals important features regarding the phase purity of superconducting samples that are masked in the dc resistance measurements. The superconducting behavior of the films, as a function of the substrate temperature during deposition and the post‐deposition annealing conditions, is discussed.
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74.78.-w Superconducting films and low-dimensional structures
79.20.Ds Laser-beam impact phenomena
81.15.Jj Ion and electron beam-assisted deposition; ion plating

Superconducting Bi‐Ca‐Sr‐Cu oxide thin films by spray pyrolysis of metal acetates

Dale F. Vaslow, Gunter H. Dieckmann, David Dawson Elli, Arthur B. Ellis, D. Scott Holmes, Anthony Lefkow, Mark MacGregor, James E. Nordman, Michael F. Petras, and Yifeng Yang

Appl. Phys. Lett. 53, 324 (1988); http://dx.doi.org/10.1063/1.100598 (3 pages) | Cited 18 times

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Superconducting Bi‐Ca‐Sr‐Cu oxide thin films have been prepared on ZrO2‐coated silicon (111) wafers by spray pyrolysis of metal acetate precursors followed by rapid annealing to 850 °C in air. Resistivity measurements indicate a broad superconducting transition with Tc onset near 90 K and zero resistivity below 60 K. The films are highly oriented with the c axis normal to the substrate surface and can be indexed to a tetragonal structure with lattice parameters of a=3.832(1) Å and c=30.78(5) Å. Both x‐ray photoelectron spectroscopy and x‐ray diffraction measurements indicate the loss of Ca to the ZrO2 buffer layer.
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74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
81.15.Lm Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids)
68.55.Nq Composition and phase identification
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