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

5 Feb 1990

Volume 56, Issue 6, pp. 503-595

Page 1 of 2 Pages Next Page | Jump to Page

Helical distributed feedback free‐electron laser

Tatsuro Akiba, Katsuya Tanaka, Masaaki Mokuno, Shuji Miyamoto, Kunioki Mima, Sadao Nakai, Shinichiro Kuruma, Kazuo Imasaki, Chiyoe Yamanaka, Masahiko Fukuda, Nobuhisa Ohigashi, and Yoshiaki Tsunawaki

Appl. Phys. Lett. 56, 503 (1990); http://dx.doi.org/10.1063/1.102775 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
Results of the implementation of a distributed feedback (DFB) reflector in a free‐electron laser (FEL) are described. The reflector was positioned in the interaction region of the FEL waveguide in order to produce narrow bandwidth features in the output spectrum. Both the DFB and wiggler were of helical configuration. The energy, current, and pulse width of the electron beam were 1.5 MeV, 100 A, and 50 ns. By employing the DFB structure the intensity of the two specific frequencies may be increased by factors of 3 and 5. These frequencies are in good agreement with those predicted by theory. Temporally radiation waveforms exhibit a double peak, revealing a sensitivity of the oscillation condition to beam energy.
Show PACS
41.60.Cr Free-electron lasers
42.60.Fc Modulation, tuning, and mode locking
42.60.By Design of specific laser systems

Free‐space radiation from electro‐optic crystals

B. B. Hu, X.‐C. Zhang, D. H. Auston, and P. R. Smith

Appl. Phys. Lett. 56, 506 (1990); http://dx.doi.org/10.1063/1.103299 (3 pages) | Cited 72 times

Full Text: | Download PDF

Show Abstract
We describe a technique to extract electro‐optic Cherenkov radiation from a LiTaO3 crystal into free space. This permits the generation of collimated beams of terahertz radiation into free space and overcomes previous limitations imposed by total internal reflection.
Show PACS
78.20.Jq Electro-optical effects
42.70.-a Optical materials

Integrated‐optical Q‐switch/mode locker for a Nd3+ fiber laser

G. Geister and R. Ulrich

Appl. Phys. Lett. 56, 509 (1990); http://dx.doi.org/10.1063/1.102751 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
An electro‐optic phase modulator and a switched directional coupler are integrated on a common LiNbO3 substrate and inserted into the cavity of a 3‐m‐long Nd3+ single‐mode fiber laser (λ≊1088 nm). Their simultaneous operation yields groups of ≊10 pulses at rates up to 2 kHz, with 50 ps pulse duration, 30 ns separation, and 200 W peak power.
Show PACS
42.60.Fc Modulation, tuning, and mode locking
42.79.Gn Optical waveguides and couplers
42.79.Hp Optical processors, correlators, and modulators
42.82.-m Integrated optics

Demonstration of optical bistability with a nonlinear frustrated‐total‐reflection filter

M. Haelterman and C. Waelbroeck

Appl. Phys. Lett. 56, 512 (1990); http://dx.doi.org/10.1063/1.102752 (3 pages) | Cited 4 times

Full Text: | Download PDF

Show Abstract
The nonlinear frustrated‐total‐reflection filter is proposed as a remarkably simple all‐optical computing element. Potential advantages of this device over nonlinear prism couplers and nonlinear thin films are presented. Optical bistability is experimentally demonstrated by using a liquid crystal as an optically nonlinear material.
Show PACS
42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
78.20.N- Thermo-optic effects
78.20.nb Photothermal effects
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation

Effect of optical phonons on femtosecond pulse propagation in coplanar striplines

G. Hasnain, K. W. Goossen, and W. H. Knox

Appl. Phys. Lett. 56, 515 (1990); http://dx.doi.org/10.1063/1.102753 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
A full‐wave analysis of the dispersion in coplanar‐type transmission lines is made including the effect of material dispersion arising from a frequency‐dependent complex dielectric constant such as due to optical phonon resonances in the substrate. The results are used to examine the distortion of femtosecond electrical pulses propagating in coplanar striplines made on ultrathin as well as thick GaAs substrates. A new closed‐form dispersion formula for coplanar lines is also reported, valid for complex dielectric constants and all values of frequency and line dimensions.
Show PACS
84.40.Az Waveguides, transmission lines, striplines
42.79.Gn Optical waveguides and couplers

Simultaneous measurement of spontaneous emission rate, nonlinear gain coefficient, and carrier lifetime in semiconductor lasers using a parasitic‐free optical modulation technique

J. Eom, C. B. Su, J. LaCourse, and R. B. Lauer

Appl. Phys. Lett. 56, 518 (1990); http://dx.doi.org/10.1063/1.102754 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
An optical modulation technique is used to determine three important parameters for 1.3 μm InGaAsP diode lasers: the rate of spontaneous emission into the guided modes, the nonlinear gain coefficient, and the carrier lifetime at threshold. These results are unaffected by electrical parasitics, and are essential to understanding the noise and modulation properties of diode lasers.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Fc Modulation, tuning, and mode locking
42.65.-k Nonlinear optics
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Measuring the coherence length of mode‐locked laser pulses in real time

Vince Dominic, X. Steve Yao, R. M. Pierce, and Jack Feinberg

Appl. Phys. Lett. 56, 521 (1990); http://dx.doi.org/10.1063/1.102755 (3 pages) | Cited 12 times

Full Text: | Download PDF

Show Abstract
We demonstrate a new technique for displaying the electric field autocorrelation function of a laser pulse in real time, using two‐beam coupling in a photorefractive crystal. This technique does not require phasematching, is simple to align, and can be used over the entire visible and near‐infrared regions of the spectrum, even with weak laser beams.
Show PACS
42.25.Kb Coherence
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.40.My Applications
42.70.-a Optical materials

Subpicosecond reflective electro‐optic sampling of electron‐hole vertical transport in surface‐space‐charge fields

Lixing Min and R. J. Dwayne Miller

Appl. Phys. Lett. 56, 524 (1990); http://dx.doi.org/10.1063/1.102734 (3 pages) | Cited 29 times

Full Text: | Download PDF

Show Abstract
A new method of electro‐optic sampling field transients, using above‐band‐gap optical probes in reflection, is analyzed theoretically and experimentally demonstrated to be within a factor of 2 as sensitive as electro‐optic sampling in transmission. The technique is ideally suited to the study of interfaces due to the surface selective nature of the evanescent field probe. Studies of the dynamics of photogenerated electron‐hole pair separation in surface‐space‐charge fields at GaAs(100)/oxide interfaces show that the hole carrier transit time is faster than 500 fs. Using longitudinal electro‐optic sampling beam geometries, this technique has an intrinsic resolution of 50 fs.
Show PACS
78.20.Jq Electro-optical effects
71.20.-b Electron density of states and band structure of crystalline solids
72.20.Dp General theory, scattering mechanisms

Preparation of ferroelectric BaTiO3 thin films by activated reactive evaporation

K. Iijima, T. Terashima, K. Yamamoto, K. Hirata, and Y. Bando

Appl. Phys. Lett. 56, 527 (1990); http://dx.doi.org/10.1063/1.103300 (3 pages) | Cited 106 times

Full Text: | Download PDF

Show Abstract
Ferroelectric BaTiO3 thin films were directly and epitaxially grown on SrTiO3 single crystal and epitaxial Pt film substrates by activated reactive evaporation. The substrate temperature was around 600 °C. For (100) oriented as‐grown films, a typical ferroelectric hysteresis loop and a maximum of dielectric constant at about 115 °C were observed. The resistivity was as high as 109 Ω cm and the breakdown voltage was 2.7 MV/cm for as‐grown BaTiO3 films.
Show PACS
77.55.-g Dielectric thin films
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
77.80.B- Phase transitions and Curie point
85.50.-n Dielectric, ferroelectric, and piezoelectric devices

Annealing of implantation damage and redistribution of impurities in SiC using a pulsed excimer laser

S. Y. Chou, Y. Chang, K. H. Weiner, T. W. Sigmon, and J. D. Parsons

Appl. Phys. Lett. 56, 530 (1990); http://dx.doi.org/10.1063/1.102735 (3 pages) | Cited 17 times

Full Text: | Download PDF

Show Abstract
A 6Hα‐SiC crystal sample, which has a surface amorphous layer resulting from a high‐dose Ga implantation, was heated using a pulsed excimer laser at several energy fluences. At an energy fluence of 1.66 J/cm2, the in situ reflectivity measurement of the surface during laser processing indicates that melting of the SiC surface has occurred. Rutherford backscattering and channeling analysis shows that the molten amorphous SiC recrystallizes using the substrate as a seed, and that the recrystallized layer has good crystal quality. Secondary‐ion mass spectrometry measurements indicate that the melting, resulting from the excimer laser pulse, results in significant redistribution of the implanted Ga. This result, the first reported for SiC, suggests that the pulsed ultraviolet process can anneal the implantation damage through a melt recrystallization process, and thus could be used to dope SiC through a gas phase adsorption process.
Show PACS
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
85.30.-z Semiconductor devices
61.72.sd Impurity concentration
61.72.sh Impurity distribution
61.72.sm Impurity gradients
66.30.J- Diffusion of impurities

Effects of hydrogen atoms on the network structure of hydrogenated amorphous and microcrystalline silicon thin films

A. Asano

Appl. Phys. Lett. 56, 533 (1990); http://dx.doi.org/10.1063/1.102736 (3 pages) | Cited 59 times

Full Text: | Download PDF

Show Abstract
By alternating the deposition of a several‐angstrom‐thick hydrogenated amorphous silicon layer and the exposure to a hydrogen plasma, the structure of the resultant hydrogenated silicon films is varied from device‐grade amorphous to microcrystalline without any change in the film precursors. On the basis of experimental results, the effects of hydrogen atoms reaching the film‐growing surface on the Si‐Si network structure are discussed.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Band offset in elastically strained InGaAs/GaAs multiple quantum wells determined by optical absorption and electronic Raman scattering

J.‐P. Reithmaier, R. Höger, H. Riechert, A. Heberle, G. Abstreiter, and G. Weimann

Appl. Phys. Lett. 56, 536 (1990); http://dx.doi.org/10.1063/1.102737 (3 pages) | Cited 56 times

Full Text: | Download PDF

Show Abstract
Pseudomorphic InGaAs/GaAs multiple quantum well structures with In contents ranging from 18 to 25% were grown by molecular beam epitaxy and investigated by optical absorption, photoluminescence, and electronic Raman scattering. Sharp exciton peaks with linewidths of ∼3 meV for the first electron to heavy hole transition are observed in the absorption spectra. The electron subband structure was investigated independently by electronic Raman scattering. The transition energies are analyzed using a four‐band effective mass Schrödinger equation taking strain into account. A conduction‐band offset ratio ΔEc/ΔEg=0.6 is found for all samples independent of In content.
Show PACS
78.30.Fs III-V and II-VI semiconductors
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.61.Ey III-V semiconductors

X‐ray photoelectron spectroscopy studies of initial growth mechanism of CdTe layers grown on (100)GaAs by organometallic vapor phase epitaxy

Syuji Sone, Mitsuru Ekawa, Kazuhito Yasuda, Yoshiyuki Sugiura, Manabu Saji, and Akikazu Tanaka

Appl. Phys. Lett. 56, 539 (1990); http://dx.doi.org/10.1063/1.102738 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
Variations of the GaAs surface conditions and the adsorption of the precursor elements of Cd and Te on the (100)GaAs substrate were studied by x‐ray photoelectron spectroscopy at the initial stage of CdTe growth by organometallic vapor phase epitaxy. The stoichiometry of GaAs substrates was found to recover by annealing in the H2 environment (500 °C, 5 min), while the surface was initially in an As‐rich condition after etching with H2SO4:H2O2:H2O (5:1:1). The preferential adsorption of Te on the GaAs surface was also observed. 〈100〉 oriented growth was obtained routinely when the GaAs surface was fully stabilized with Te after the H2 anneal under the above conditions. 〈111〉 oriented growth resulted when dimethylcadmium was first introduced after the anneal.
Show PACS
81.15.Kk Vapor phase epitaxy; growth from vapor phase
82.80.-d Chemical analysis and related physical methods of analysis
68.35.B- Structure of clean surfaces (and surface reconstruction)

Hydrogen passivation of Zn acceptors in InGaAs during reactive ion etching

Martin Moehrle

Appl. Phys. Lett. 56, 542 (1990); http://dx.doi.org/10.1063/1.102739 (3 pages) | Cited 14 times

Full Text: | Download PDF

Show Abstract
It is shown that the use of hydrogen‐containing gases such as CHF3/H2, CHF3, CH4 /H2, and CH4 /He in reactive ion etching processes leads to a drastic reduction of the concentration of electrically active acceptors in a thin layer at the surface of highly Zn‐doped InGaAs. This passivation effect leads to strongly nonlinear current/voltage characteristics of nonalloyed Ti/Pt/Au contacts when applied directly on as‐treated p++ ‐InGaAs layers. The observed deactivation of acceptors is inferred to be caused by hydrogen since no such an effect was found with the use of hydrogen‐free etching gases.
Show PACS
73.40.Cg Contact resistance, contact potential
85.40.Ls Metallization, contacts, interconnects; device isolation
73.40.Ns Metal-nonmetal contacts
61.72.U- Doping and impurity implantation

Novel contactless electroreflectance spectroscopy of semiconductors

M. Gal and C. Shwe

Appl. Phys. Lett. 56, 545 (1990); http://dx.doi.org/10.1063/1.102740 (3 pages) | Cited 16 times

Full Text: | Download PDF

Show Abstract
Optical reflectance difference technique has been applied to semiconductors. It has been demonstrated that differential reflectance spectroscopy (DR) can be equivalent to contactless electromodulation. The measured DR spectra of GaAs are comparable to the published electroreflectance data and show marked improvement in the signal‐to‐noise ratio over the photoreflectance spectra of the same samples. We have used this method to study the confined energy levels in InGaAs/GaAs multiple quantum wells and have found good agreement with the theoretically predicted values. We conclude that DR is a viable alternative to photoreflectance as a contactless electromodulation technique.
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.20.Jq Electro-optical effects

Research on resonant tunneling by fast neutron irradiation

J. M. Mao, J. M. Zhou, R. L. Zhang, W. M. Jin, C. L. Bao, and Y. Huang

Appl. Phys. Lett. 56, 548 (1990); http://dx.doi.org/10.1063/1.102741 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
Resonant tunneling by fast neutron irradiation with doses from 1×1012 to 1×1016 n/cm2 was studied. We observed that peak and valley positions shifted to higher voltages, and peak‐to‐valley ratios decreased with higher doses in static current‐voltage characteristics. Several models which take into account ionized impurities were used to give consistent explanation to such phenomena.
Show PACS
73.40.Gk Tunneling
73.61.Ey III-V semiconductors
61.80.Hg Neutron radiation effects
72.10.Fk Scattering by point defects, dislocations, surfaces, and other imperfections (including Kondo effect)

Resonant interband tunneling through a 110 nm InAs quantum well

R. Beresford, L. F. Luo, K. F. Longenbach, and W. I. Wang

Appl. Phys. Lett. 56, 551 (1990); http://dx.doi.org/10.1063/1.102742 (3 pages) | Cited 17 times

Full Text: | Download PDF

Show Abstract
The mechanism of resonant interband tunneling in polytype heterostructures of GaSb/AlSb/InAs gives excellent peak‐to‐valley current ratios due to the band‐gap blocking of the nonresonant current components. Using InAs as the base in a double‐barrier polytype heterostructure, it is possible to demonstrate resonant tunneling at room temperature through a quantum well as wide as 110 nm. At this width, which is about 20 times larger than that typically used in resonant tunneling diodes in the GaAs/AlGaAs system, the peak‐to‐valley ratio is 44:1 (77 K). Significant negative differential resistance is observed even for 240 nm wells. The projected device response time for a resonant tunneling transistor with a wide InAs quantum base is more than five times faster than for a GaAs device, due to the reduced base resistance.
Show PACS
73.40.Gk Tunneling
71.23.-k Electronic structure of disordered solids
71.20.Nr Semiconductor compounds
71.20.Ps Other inorganic compounds

Damage‐induced uphill diffusion of implanted Mg and Be in GaAs

Heyward G. Robinson, Michael D. Deal, and David A. Stevenson

Appl. Phys. Lett. 56, 554 (1990); http://dx.doi.org/10.1063/1.102743 (3 pages) | Cited 22 times

Full Text: | Download PDF

Show Abstract
The redistribution of Be and Mg implants upon post‐implant annealing is studied in order to evaluate the influence of implant damage on the diffusion process. Rapid uphill diffusion is observed in the peak of Mg implants in GaAs, whereas Be implants show only uniform, concentration‐dependent diffusion. This behavior is explained by the substitutional‐interstitial‐diffusion mechanism and computer simulations of damage‐produced point defects. In the region of uphill diffusion, the dopants diffuse from areas of excess interstitials toward areas of excess vacancies. A critical concentration of point defects is necessary to initiate uphill diffusion. Uphill diffusion can be induced in Be implants by co‐implanting with a heavier element such as Ar.
Show PACS
66.30.J- Diffusion of impurities
61.72.U- Doping and impurity implantation

Formation and Schottky barrier height of metal contacts to β‐SiC

J. R. Waldrop and R. W. Grant

Appl. Phys. Lett. 56, 557 (1990); http://dx.doi.org/10.1063/1.102744 (3 pages) | Cited 31 times

Full Text: | Download PDF

Show Abstract
Formation of Schottky barrier contacts to n‐type β‐SiC(100) was systematically investigated for several metals with various physical and chemical properties. The metals (Pd, Au, Co, Ti, Ag, Tb, and Al) were deposited onto oxygen terminated (∼1 monolayer) surfaces. Metal/β‐SiC interface chemistry and Schottky barrier height ϕB during contact formation were obtained by x‐ray photoemission spectroscopy; the corresponding electrical properties of thick contacts were characterized by capacitance‐voltage and current‐voltage methods. The metal/β‐SiC interface is unreactive at room temperature. X‐ray photoemission spectroscopy and electrical measurements demonstrate that these metal contacts exhibit a wide range of ϕB , 0.95–0.16 eV; within this range an individual contact ϕB value depends strongly on the metal work function in general accord with the Schottky–Mott limit.
Show PACS
73.40.Ns Metal-nonmetal contacts
73.30.+y Surface double layers, Schottky barriers, and work functions
68.35.Dv Composition, segregation; defects and impurities
85.30.Hi Surface barrier, boundary, and point contact devices

Enhancement of lateral solid phase epitaxy over SiO2 using a densified and thinned amorphous Si layer

K. Kusukawa, M. Moniwa, M. Ohkura, and E. Takeda

Appl. Phys. Lett. 56, 560 (1990); http://dx.doi.org/10.1063/1.103301 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
Formation of a thin‐film silicon‐on‐insulator structure by lateral solid phase epitaxy of amorphous Si is described. Thinning of the amorphous Si layer after deposition and densification in an ultrahigh vacuum, prior to solid phase epitaxy, successfully enhances the lateral growth length. In addition, the crystallinity of thin silicon‐on‐insulator layers formed by this technique is found to be better than that achieved by the conventional method.
Show PACS
64.70.K- Solid-solid transitions

Material properties of p‐type GaAs at large dopings

Sandip Tiwari and Steven L. Wright

Appl. Phys. Lett. 56, 563 (1990); http://dx.doi.org/10.1063/1.102745 (3 pages) | Cited 39 times

Full Text: | Download PDF

Show Abstract
We summarize the room‐temperature minority‐carrier mobility, minority‐carrier lifetime, and effective band‐gap shrinkage for p‐type GaAs at large dopings, as determined from measurements on heterostructure bipolar transistors and published literature. The minority‐carrier mobilities are significantly smaller than the majority‐carrier mobilities, the lifetime data show a change in dependence on doping at 1×1019 cm−3, and the effective band‐gap shrinkage is ≊5% at 1×1019 cm−3. The fits to electrical parameters described here should be of interest in modeling of minority‐carrier devices.
Show PACS
72.20.Fr Low-field transport and mobility; piezoresistance
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
72.80.Ey III-V and II-VI semiconductors
85.30.De Semiconductor-device characterization, design, and modeling

Yb‐doped InP grown by metalorganic vapor phase epitaxy using a beta‐diketonate precursor

D. M. Williams and B. W. Wessels

Appl. Phys. Lett. 56, 566 (1990); http://dx.doi.org/10.1063/1.102746 (3 pages) | Cited 10 times

Full Text: | Download PDF

Show Abstract
Yb‐doped InP has been prepared by metalorganic vapor phase epitaxy using a Yb fluorinated beta‐diketonate. The doped layers were n type with carrier concentrations ranging from 0.6 to 17×1015 cm−3. The doped layers exhibited the characteristic Yb+3‐4f photoluminescent emission at 1.23 eV. The low‐temperature photoluminescence indicates the association of Yb with other centers to form complexes.
Show PACS
71.55.Eq III-V semiconductors
78.55.Cr III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Measurement of the valence‐band offset in strained Si/Ge (100) heterojunctions by x‐ray photoelectron spectroscopy

E. T. Yu, E. T. Croke, T. C. McGill, and R. H. Miles

Appl. Phys. Lett. 56, 569 (1990); http://dx.doi.org/10.1063/1.102747 (3 pages) | Cited 29 times

Full Text: | Download PDF

Show Abstract
We have used x‐ray photoelectron spectroscopy to measure the valence‐band offset in situ for strained Si/Ge (100) heterojunctions grown by molecular beam epitaxy. Si 2p and Ge 3d core level to valence‐band‐edge binding energies and Si 2p to Ge 3d core level energy separations were measured as functions of strain, and strain configurations in all samples were determined using x‐ray diffraction. Our measurements yield valence‐band offset values of 0.83±0.11 eV and 0.22±0.13 eV for Ge on Si (100) and Si on Ge (100), respectively. If we assume that the offset between the weighted averages of the light hole, heavy hole, and spin‐orbit valence bands in Si and Ge is independent of strain, we obtain a discontinuity in the average valence‐band edge of 0.49±0.13 eV.
Show PACS
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.61.Cw Elemental semiconductors
73.61.Jc Amorphous semiconductors; glasses
73.61.Le Other inorganic semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Column III‐column V sublattice interaction via Zn and Si impurity‐induced layer disordering of 13C‐doped AlxGa1−xAs‐GaAs superlattices

L. J. Guido, J. S. Major, J. E. Baker, N. Holonyak, B. T. Cunningham, and G. E. Stillman

Appl. Phys. Lett. 56, 572 (1990); http://dx.doi.org/10.1063/1.102748 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
Experiments are described employing secondary‐ion mass spectroscopy (SIMS) to study the stability of 13C‐doped Al0.5Ga0.5As‐GaAs superlattices against Zn and Si impurity‐induced layer disordering (IILD). The modulation depth of the SIMS 27Al and 13C signals is used as a sensitive probe of column III and column V sublattice interdiffusion. The data show that CAs is much more stable against Zn and Si IILD than the column III superlattice host crystal itself. The minor enhancement of CAs diffusion via the column III disordering agents, which is present to a significant extent for Si IILD but almost nonexistent for Zn IILD, suggests that there is no direct interchange of column III and column V sublattice atoms. The Zn and Si enhancement of carbon diffusion is probably caused by local Coulombic interaction between the diffusing Zn+i and Si+III species and the C−As acceptor.
Show PACS
66.30.J- Diffusion of impurities
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.15.Kk Vapor phase epitaxy; growth from vapor phase
61.72.S- Impurities in crystals

Effect of oxygen plasma annealing on superconducting properties of Bi2(Sr,Ca)3Cu2Ox and YBa2Cu3O7−δ thin films

T. Yoshitake, S. Miura, J. Fujita, N. Shohata, H. Igarashi, T. Satoh, A. Sekiguchi, and K. Katoh

Appl. Phys. Lett. 56, 575 (1990); http://dx.doi.org/10.1063/1.103302 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
Thin films of the Bi2(Sr,Ca)3Cu2Ox and YBa2Cu3O7−δ system were annealed at 400 °C in a high‐density oxygen plasma and its effect on superconducting properties was investigated. After being annealed in the oxygen plasma, their superconducting transition temperatures decreased by about 10 K and 2 K, respectively, and the c‐axis lattice constants of these films were also found to decrease as a result of the annealing in the oxygen plasma. These results suggest that excessive oxygen incorporated into the films by the annealing in the oxygen plasma caused the excessive hole carriers, which deteriorated the superconducting transition temperatures of these films.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
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
81.40.Rs Electrical and magnetic properties related to treatment conditions
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close