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

7 Feb 1994

Volume 64, Issue 6, pp. 673-804

Page 2 of 2 Pages Previous Page | Jump to Page

Nondestructive photoacoustic detection of exciton resonances in GaAs/AlGaAs multiple quantum well structures

J. H. Chu, Y. H. Bak, J. H. Kim, H. L. Park, S. H. Park, U. Kim, J. G. Choi, and I. G. Kim

Appl. Phys. Lett. 64, 745 (1994); http://dx.doi.org/10.1063/1.111053 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
We report nondestructive observations of both heavy‐hole and light‐hole excitons in the GaAs/AlGaAs multiple quantum wells (MQWs) using photoacoustic spectroscopy. The absorption spectra were measured by the gas‐microphone photoacoustic technique with a minimal volume cell and grazing incidence method. Two distinct peaks were clearly observed in the photoacoustic signal and phase spectra of the MQW at room temperature. A photoreflectance measurement for the given MQW structure revealed that two peaks originated from the heavy‐hole and light‐hole excitonic resonances.
Show PACS
78.66.Fd III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

Growth temperature dependence of the Si(001)/SiO2 interface width

Mau‐Tsu Tang, K. W. Evans‐Lutterodt, M. L. Green, D. Brasen, K. Krisch, L. Manchanda, G. S. Higashi, and T. Boone

Appl. Phys. Lett. 64, 748 (1994); http://dx.doi.org/10.1063/1.111054 (3 pages) | Cited 17 times

Full Text: | Download PDF

Show Abstract
The growth temperature dependence of the thin thermally oxidized Si(001)/SiO2 interface width was studied using synchrotron x‐ray diffraction. Nine samples with oxide thickness of about 100 Å were studied, with growth temperatures ranging from 800 to 1200 °C. The oxides were prepared by rapid thermal oxidation. We found that interfacial roughness decreases linearly with increasing growth temperature, with a measured interface width of 2.84 Å for the sample grown at 800 °C, and 1.76 Å when grown at 1200 °C.
Show PACS
81.65.-b Surface treatments
68.55.-a Thin film structure and morphology
68.35.-p Solid surfaces and solid-solid interfaces: structure and energetics

InAlAs/InGaAs metal‐semiconductor‐metal photodiodes heteroepitaxially grown on Si substrates

T. Sasaki, T. Enoki, M. Tachikawa, M. Sugo, and H. Mori

Appl. Phys. Lett. 64, 751 (1994); http://dx.doi.org/10.1063/1.111055 (3 pages) | Cited 6 times

Full Text: | Download PDF

Show Abstract
To study performance and reproducibility of photodiodes (PDs) on Si in the long‐wavelength region, InAlAs/InGaAs metal‐semiconductor‐metal PDs were fabricated on high‐quality heteroepitaxial InP layers on Si substrates. A dark current of 0.5–2×10−8 A and a responsivity of 0.05–0.15 A/W were reproducibly obtained, at least at one of the ±5 V bias voltages. These dark currents and responsivity are similar to those of PDs with the same structure fabricated on InP substrates. The PDs on Si have pulse responses with full widths at half‐maximum of 150–600 ps.
Show PACS
85.60.Gz Photodetectors (including infrared and CCD detectors)
73.40.Sx Metal-semiconductor-metal structures
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
72.40.+w Photoconduction and photovoltaic effects

Gas and adsorbate excitation pathways in synchrotron radiation excited Si growth using disilane

H. Akazawa, M. Nagase, and Y. Utsumi

Appl. Phys. Lett. 64, 754 (1994); http://dx.doi.org/10.1063/1.111056 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
We studied reaction kinetics in synchrotron radiation excited chemical vapor deposition of Si using disilane. It was found that the growth rate depends on temperature in the irradiated region but not in the nonirradiated region. Growth in the irradiated region occurs as a result of photolysis of disilane molecules weakly trapped on the surface followed by the formation of a hydrogenated Si network. On the other hand, in the nonirradiated region, growth occurs as a result of layer‐by‐layer sticking and the elimination of surface hydrogen by a fragment species generated by photolysis of gas‐phase disilane. The reaction model is consistent with properties of the grown Si film.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.50.Bc Processes caused by infrared radiation
82.50.Hp Processes caused by visible and UV light
68.55.-a Thin film structure and morphology

Strain effects on the spectra of spontaneously ordered GaxIn1−xP

Su‐Huai Wei and Alex Zunger

Appl. Phys. Lett. 64, 757 (1994); http://dx.doi.org/10.1063/1.111057 (3 pages) | Cited 20 times

Full Text: | Download PDF

Show Abstract
Spontaneous (111) CuPt‐like ordering has been widely observed in GaxIn1−xP lattice matched (x=x0) to a GaAs(001) substrate. This leads to a band‐gap reduction ΔEg and to a valence‐band splitting ΔE12. We explore here the consequence of the coexistence of (001) epitaxial strain (produced by selecting x≠x0) and (111) chemical ordering. This leads to distinct changes in ΔEg and ΔE12 which could serve as new fingerprints of ordering.    
Show PACS
71.70.Ch Crystal and ligand fields
68.55.-a Thin film structure and morphology
78.66.Fd III-V semiconductors
73.61.Ey III-V semiconductors

Effect of zinc impurity‐induced disordering on the refractive index of GaAs/AlGaAs multiquantum wells

Sang‐Kook Han, Sanjai Sinha, and Ramu V. Ramaswamy

Appl. Phys. Lett. 64, 760 (1994); http://dx.doi.org/10.1063/1.111030 (3 pages) | Cited 4 times

Full Text: | Download PDF

Show Abstract
We report on the variation of the refractive index of a GaAs/AlGaAs multiquantum well of well width 6.5 nm and barrier width 19 nm, introduced by zinc impurity‐induced disordering. We employ a structure consisting of several uncoupled, multiquantum well ridge waveguides with tapered disordering across the transverse direction. The refractive index changes have been deduced as a function of the interdiffusion length of Ga/Al by the use of an interference technique. We measured a maximum index change of 0.083 and 0.062 for significant disordering (Ld=6.6 nm) at 35 and 100 meV below the band edge of the undisordered multiquantum well, respectively.
Show PACS
78.66.Fd III-V semiconductors
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
61.72.uj III-V and II-VI semiconductors
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials

Deposition of in situ boron‐doped polycrystalline silicon films at reduced pressures

Horng‐Chih Lin, Hsiao‐Yi Lin, Chun‐Yen Chang, Tan‐Fu Lei, P. J. Wang, Ray‐Chern Deng, and Jandel Lin

Appl. Phys. Lett. 64, 763 (1994); http://dx.doi.org/10.1063/1.111005 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
We report on the deposition of in situ boron‐doped polycrystalline Si films on the SiO2 surface with reduced growth pressures at 550 °C. The deposition rate of these films decreased as the doping level was greater than 1019 cm−3. Such a result is in sharp contrast to what has been observed previously for similar films grown with conventional low pressure chemical vapor deposition techniques. It was also found that the incubation time prior to the deposition of these films diminished as the doping level was increased to 3×1020 cm−3 or higher. It is attributed to the preferential adsorption of boron atoms on the SiO2 surface at the initial stage of growth, which facilitates the nucleation of Si.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Photoluminescence study of strong interdiffusion in CdTe/CdMnTe quantum wells induced by rapid thermal annealing

D. Tönnies, G. Bacher, A. Forchel, A. Waag, and G. Landwehr

Appl. Phys. Lett. 64, 766 (1994); http://dx.doi.org/10.1063/1.111006 (3 pages) | Cited 22 times

Full Text: | Download PDF

Show Abstract
Thermally induced interdiffusion in CdTe/CdMnTe quantum wells was investigated by photoluminescence spectroscopy. The single quantum well structures were grown by molecular beam epitaxy annealed by rapid thermal annealing for 1 min at temperatures between 380 and 520 °C. A blue shift close to the barrier energy was observed indicating an almost perfect interdiffusion between the well and the barrier material. We derive an activation energy of 2.8 eV for the interdiffusion process from a Fickian diffusion model applied to our experiments.
Show PACS
68.35.Fx Diffusion; interface formation
66.30.Ny Chemical interdiffusion; diffusion barriers
78.55.Et II-VI semiconductors

InP on Si(111): Accommodation of lattice mismatch and structural properties

A. Krost, F. Heinrichsdorff, D. Bimberg, and H. Cerva

Appl. Phys. Lett. 64, 769 (1994); http://dx.doi.org/10.1063/1.111007 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
The growth of InP by low‐pressure metalorganic chemical vapor deposition on vicinal Si(111), misoriented 3° towards [112], is reported. By double crystal x‐ray diffraction an order of magnitude improvement in structural quality is measured as compared to InP on Si(001). From high resolution electron microscopy near the interface a heavily twinned region of 25 nm in thickness is found with microtwins having their twin planes parallel to the Si(111) surface. In this region the 8% misfit between InP and Si is completely accommodated in one dimension by partial dislocations having Burgers vectors a/6〈112〉 (Schockley partial dislocations) in the (111) surface plane which are associated with the formation of the thin twinned region close to the interface. Above this zone the crystallographic orientations of the InP are identical to those of the Si substrate.
Show PACS
68.55.-a Thin film structure and morphology
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Solid‐state reaction‐mediated low‐temperature bonding of GaAs and InP wafers to Si substrates

Z. Ma, G. L. Zhou, H. Morkoç, L. H. Allen, and K. C. Hsieh

Appl. Phys. Lett. 64, 772 (1994); http://dx.doi.org/10.1063/1.111008 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
We report a low‐temperature wafer bonding method for the realization of integration of GaAs‐ and InP‐based optoelectronic devices with Si microelectronic devices. This method uses a Au‐Ge eutectic alloy as the bonding material sandwiched between GaAs and Si wafers, and between InP and Si wafers. The bonding process was carried out at 280–300 °C by taking advantage of the low‐temperature solid‐state reactions occurring at GaAs/Au‐Ge, InP/Au‐Ge, and Si/Au‐Ge interfaces. Both the simple mechanical test and standard thermal cycling test prove excellent structural integrity of the joined wafers. Structural analyses reveal only limited interfacial reactions as well as solid‐phase epitaxial regrowth of GeSi alloys on the Si substrate.
Show PACS
68.35.-p Solid surfaces and solid-solid interfaces: structure and energetics
85.40.Hp Lithography, masks and pattern transfer

Performance improvement of amorphous silicon thin‐film transistors with SiO2 gate insulator by N2 plasma treatment

Jeong Hyun Kim, Eui Yeal Oh, Byung Chul Ahn, Donggil Kim, and Jin Jang

Appl. Phys. Lett. 64, 775 (1994); http://dx.doi.org/10.1063/1.111009 (2 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
We studied the performance improvement of hydrogenated amorphous silicon (a‐Si:H) thin‐film transistor (TFT) using atmospheric pressure chemical vapor deposition (APCVD) SiO2 as a gate insulator. The threshold voltage and the subthreshold swing decrease remarkably by N2 plasma treatment on the APCVD SiO2 surface even though the field effect mobility changes little, indicating that the interface state density around the Fermi level is reduced significantly by N2 plasma treatment. We obtained the high performance a‐Si:H TFT with the field effect mobility of 1.25 cm2/V s, the threshold voltage of 3.5 V and the subthreshold swing of 0.45 V/dec.
Show PACS
85.30.Tv Field effect devices
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.20.At Surface states, band structure, electron density of states

High Tc superconductor bolometer with record performance

J. C. Brasunas and B. Lakew

Appl. Phys. Lett. 64, 777 (1994); http://dx.doi.org/10.1063/1.111010 (2 pages) | Cited 27 times

Full Text: | Download PDF

Show Abstract
We have used prethinned sapphire substrates to make a YBa2Cu3O7−x thin‐film, transition‐edge bolometer with peak detectivity of 6×109 cm Hz1/2/W near 4 Hz and 90 K. This is a new record for high Tc superconductor bolometers, and is comparable to the best detectivity yet achieved for a thermal‐type infrared detector with no more than moderate cooling (liquid‐nitrogen temperature and above). We discuss some simple improvements which may push the detectivity above 1010.
Show PACS
85.25.Qc Superconducting surface acoustic wave devices and other superconducting devices
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
74.78.-w Superconducting films and low-dimensional structures

Epitaxial growth and properties of YBa2Cu3O7−y/LaSrGaO4/YBa2Cu3O7−y trilayer structures

S. Hontsu, N. Mukai, J. Ishii, T. Kawai, and S. Kawai

Appl. Phys. Lett. 64, 779 (1994); http://dx.doi.org/10.1063/1.111011 (3 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
We report the successful synthesis of insulating LaSrGaO4(LSGO) thin films and YBa2Cu3O7−y(YBCO)/LSGO heteroepitaxial multilayer structures using a pulsed laser deposition technique. SrTiO3(STO)(100) was used as a substrate. The formation of highly c‐axis oriented YBCO/LSGO/YBCO trilayer structures is demonstrated. Epitaxial YBCO films on LSGO//STO and LSGO/YBCO//STO have a zero resistance temperature of 88.5 and 88.3 K, respectively. Sandwich‐type YBCO/LSGO/YBCO junctions were produced by a suitable patterning technique. The observed (dI/dV)‐V characteristics exhibit a clear single gap structure (width ∼26 meV) at temperatures below 30 K.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
68.55.-a Thin film structure and morphology
81.15.Fg Pulsed laser ablation deposition

Large normal resistance and THz electromagnetic‐wave response in YBaCuO step‐edge microbridge Josephson junction

Yoshito Fukumoto, Seiji Hayashi, Rikuo Ogawa, and Yoshio Kawate

Appl. Phys. Lett. 64, 782 (1994); http://dx.doi.org/10.1063/1.111012 (3 pages) | Cited 4 times

Full Text: | Download PDF

Show Abstract
A YBaCuO Josephson junction with a large normal resistance (R) was fabricated and characterized. The junction exhibited an extremely sharp transition on the current‐voltage curve with R=10.8 Ω and IcR=1.8 mV at 15 K. The temperature dependence of critical current (Ic) of the junction was Ic∝(1−T/Tc), while another junction with a smaller R (0.57 Ω) showed a dependence of Ic∝(1−T/Tc)2. The difference can be explained by a picture of a grain boundary junction as a parallel array of superconductor‐normal‐superconductor and superconductor‐insulator‐superconductor elements. From the results of 110 GHz mixing experiments, it was shown that the present junction could be operative for electromagnetic waves over 2 THz.
Show PACS
85.25.Dq Superconducting quantum interference devices (SQUIDs)
74.78.-w Superconducting films and low-dimensional structures
74.50.+r Tunneling phenomena; Josephson effects
74.45.+c Proximity effects; Andreev reflection; SN and SNS junctions

Fabrication of Josephson junctions using an Al/Ta/Nb structure for x‐ray detection

Shin’ichi Morohashi, Kohtaroh Gotoh, and Satoshi Komiya

Appl. Phys. Lett. 64, 785 (1994); http://dx.doi.org/10.1063/1.111013 (3 pages) | Cited 4 times

Full Text: | Download PDF

Show Abstract
We fabricated Josephson junctions using an Al/Ta/Nb structure for x‐ray detection. We selected a Ta layer to be the absorber of quasiparticles generated by incident x rays to the junction because of the long lifetime of quasiparticles and the absorption efficiency for x rays. A Nb layer served not only as a barrier for quasiparticle rejection, but also as a buffer layer for deposition of a body centered cubic Ta layer without heating during deposition. An Al layer acted as not only an overlayer for the formation of the AlOx barrier, but also as a layer for quasiparticle trapping. The Nb/AlOx‐Al/Ta/Nb junction showed excellent current‐voltage characteristics.
Show PACS
85.25.Cp Josephson devices
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors

Noise characteristics of YBa2Cu3O7−δ /CaRuO3/YBa2Cu3O7−δ Josephson junctions

K. E. Myers, K. Char, M. S. Colclough, and T. H. Geballe

Appl. Phys. Lett. 64, 788 (1994); http://dx.doi.org/10.1063/1.111014 (3 pages) | Cited 12 times

Full Text: | Download PDF

Show Abstract
The noise characteristics of YBa2Cu3O7−δ/CaRuO3/YBa2Cu3O7−δ edge junctions are reported. The junctions exhibit low 1/f noise in the range of operating temperatures from 65 to 77 K. At lower temperatures the level of 1/f noise increases, and in addition, telegraph noise dominates the noise power spectrum at discrete current biases that are junction dependent. The characteristic frequency of a particular switching process increases with temperature but may increase or decrease with increased bias current. These results are consistent with a description of the superconductor‐metal interface in which oxygen deficiency and/or disorder gives rise to localized states which trap carriers and lead to noise in the junction transmission.
Show PACS
74.40.-n Fluctuation phenomena
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

Magnetoresistance in Au‐Co‐B heterogeneous alloys

R. von Helmolt, J. Wecker, and K. Samwer

Appl. Phys. Lett. 64, 791 (1994); http://dx.doi.org/10.1063/1.111015 (3 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
Au‐Co and Au‐Co‐B alloys have been prepared by rapid solidification, followed by heat treatment. The precipitation of the ferromagnetic phases Co and Co2B in the Au matrix phase has been observed during annealing. At room temperature, both magnetization and magnetoresistance are determined by the superparamagnetic behavior of the ferromagnetic particles. The magnetoresistance is believed to have the same origin as that in multilayers and granular films. Both Co particles and the precipitates of the Co2B intermetallic phase give rise to a high magnetoresistance. The magnetoresistance effect was less than 1% in the as‐quenched samples and increased to about 3% after an appropriate heat treatment.
Show PACS
72.15.Gd Galvanomagnetic and other magnetotransport effects
75.50.Cc Other ferromagnetic metals and alloys
81.40.Rs Electrical and magnetic properties related to treatment conditions
81.05.Rm Porous materials; granular materials

Ruderman–Kittel–Kasuya–Yosida interaction between zero‐dimensional and one‐dimensional ferromagnetic inclusions in a matrix of nonmagnetic metal

G. M. Genkin and M. V. Sapozhnikov

Appl. Phys. Lett. 64, 794 (1994); http://dx.doi.org/10.1063/1.111016 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
Work is devoted to the calculation of Ruderman–Kittel–Kasuya–Yosida interaction between inclusions of spherical shape (zero‐dimensional) and whiskerical shape (one‐dimensional). The conservation of oscillating character of the interaction independently of ferromagnetic particle sizes is shown.
Show PACS
75.10.Lp Band and itinerant models
75.50.Tt Fine-particle systems; nanocrystalline materials
75.30.Et Exchange and superexchange interactions
75.30.Hx Magnetic impurity interactions

Nanostructure of mechanically alloyed zinc‐bonded Sm2Fe17Nx magnets

C. Kuhrt, H. Cerva, and L. Schultz

Appl. Phys. Lett. 64, 797 (1994); http://dx.doi.org/10.1063/1.111017 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
The nanostructure of mechanically alloyed Sm2Fe17Nx‐based magnets, which were Zn‐bonded by pressure‐assisted sintering at elevated temperature, was characterized by means of high‐resolution and analytical transmission electron microscopy. The hard magnetic Sm2Fe17Nx grains were found to be about 100 nm in average size separated by a nonmagnetic Zn‐rich phase of 5–10 nm in thickness. High‐resolution imaging revealed various lattice planes in the grain boundary region which may be attributed to the presence of Γ‐Fe‐Zn. Obviously, this nonmagnetic phase at the grain boundaries provides additionally magnetic decoupling of the individual Sm2Fe17Nx grains, which is responsible for the coercivity increase of up to 50% induced by the pressure‐assisted Zn bonding process.
Show PACS
75.50.Vv High coercivity materials
75.50.Bb Fe and its alloys
81.05.Rm Porous materials; granular materials
81.20.Ev Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
FREE

Comment on ‘‘Surface‐emitting second‐harmonic generator by intersubband transition in asymmetric quantum wells with slab waveguide [Appl. Phys. Lett. 62, 1502 (1993)]

V. Berger, P. Bois, and E. Rosencher

Appl. Phys. Lett. 64, 800 (1994); http://dx.doi.org/10.1063/1.111963 (1 page) | Cited 2 times

Full Text: | Download PDF

Abstract Unavailable
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Fd III-V semiconductors
FREE

Response to ‘‘Comment on ‘Surface‐emitting second‐harmonic generator by intersubband transition in asymmetric quantum wells with slab waveguides’’’ [Appl. Phys. Lett. 63, 1502 (1993)]

Z. Chen, D. Cui, M. Li, H. Lu, and G. Yang

Appl. Phys. Lett. 64, 800 (1994); http://dx.doi.org/10.1063/1.111018 (2 pages) | Cited 3 times

Full Text: | Download PDF

Abstract Unavailable
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Fd III-V semiconductors
FREE

Comment on ‘‘Exact and moment equation modeling of electron transport in submicron structures’’ [Appl. Phys. Lett. 59, 1743 (1991)]

Matthias Curow

Appl. Phys. Lett. 64, 802 (1994); http://dx.doi.org/10.1063/1.111019 (2 pages) | Cited 6 times

Full Text: | Download PDF

Abstract Unavailable
Show PACS
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
72.20.Dp General theory, scattering mechanisms
72.20.Ht High-field and nonlinear effects
FREE

Response to ‘‘Comment on ‘Exact and moment equation modeling of electron transport in submicron structures’ ’’ [Appl. Phys. Lett. 59, 1743 (1991)]

Bernard J. Geurts

Appl. Phys. Lett. 64, 803 (1994); http://dx.doi.org/10.1063/1.111020 (2 pages)

Full Text: | Download PDF

Abstract Unavailable
Show PACS
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
72.20.Dp General theory, scattering mechanisms
72.20.Ht High-field and nonlinear effects
Page 2 of 2 Pages Previous Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close