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

3 Aug 1992

Volume 61, Issue 5, pp. 503-616

Page 1 of 2 Pages Next Page | Jump to Page

Antiresonant reflecting optical waveguide‐type, single‐mode diode lasers

L. J. Mawst, D. Botez, C. Zmudzinski, and C. Tu

Appl. Phys. Lett. 61, 503 (1992); http://dx.doi.org/10.1063/1.108475 (3 pages) | Cited 15 times

Full Text: | Download PDF

Show Abstract
Antiresonant reflecting optical waveguide (ARROW)‐type diode lasers have been demonstrated for the first time. The ARROW structure is made in the lateral direction (i.e., the plane of the junction) by two‐step metalorganic chemical vapor deposition. Stable, diffraction‐limited beam operation is achieved to 0.6 W peak pulsed power and 20× threshold. The power contained within the diffraction‐limited beam pattern is 420 mW with 60% of the energy residing in the central, diffraction‐limited lobe. Modal calculations for ARROW lasers confirm very strong intermodal discrimination. Theoretical calculations and preliminary experimental data show that up to 90% of the energy can be obtained in the central lobe (475 mW diffraction‐limited power).
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Blue stimulated emission from a ZnSe p‐n diode at low temperature

S. Y. Wang, I. Hauksson, J. Simpson, H. Stewart, S. J. A. Adams, J. M. Wallace, Y. Kawakami, K. A. Prior, and B. C. Cavenett

Appl. Phys. Lett. 61, 506 (1992); http://dx.doi.org/10.1063/1.107869 (3 pages) | Cited 15 times

Full Text: | Download PDF

Show Abstract
Laser diode structures have been fabricated using molecular beam epitaxy with iodine from an electrochemical source for the n‐type doping and nitrogen from a plasma source for the p‐type doping. CV profiling using electrochemical etching shows uniform p doping of 4×1017 cm−3 and n doping of 1×1018 cm−3. Under pulsed current excitation blue emission at 470 nm is observed at room temperature which increases in intensity at liquid helium temperatures. Above a current density threshold of 50 A cm−2 stimulated emission is observed between 448–473 nm with a complicated mode structure.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

Normal incidence intersubband optical transition in GaSb/InAs superlattices

H. H. Chen, M. P. Houng, Y. H. Wang, and Yia‐Chung Chang

Appl. Phys. Lett. 61, 509 (1992); http://dx.doi.org/10.1063/1.107870 (3 pages) | Cited 14 times

Full Text: | Download PDF

Show Abstract
A novel intersubband optical transition, incorporating interband and p‐type intersubband optical transition mechanisms, in a suitably designed GaSb/InAs superlattice is proposed. Such a structure utilizes the strong mixing of GaSb light‐hole band with InAs conduction band and the heavy‐hole to light‐hole intervalence‐subband transition in the GaSb/InAs superlattice to obtain a strong normal incidence photoabsorption coefficient (over 8.0×104 cm−1) at a wavelength near 10 μm.
Show PACS
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Sample depolarization effects from thin films of ZnS on GaAs as measured by spectroscopic ellipsometry

G. E. Jellison and J. W. McCamy

Appl. Phys. Lett. 61, 512 (1992); http://dx.doi.org/10.1063/1.107871 (3 pages) | Cited 33 times

Full Text: | Download PDF

Show Abstract
Thin films of ZnS grown on GaAs by laser ablation are examined using spectroscopic two‐channel polarization modulation ellipsometry (2‐C PME). It is found that variations in the film thickness over the illumination spot result in the quasidepolarization of the incident light, which can be measured directly using 2‐C PME. Quantitative fits of the ellipsometry data using a distribution‐of‐thicknesses model agree with independent reflectivity measurements of the thickness gradient, and allow for the accurate determination of the optical functions of the ZnS film.
Show PACS
68.55.-a Thin film structure and morphology
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
07.60.Fs Polarimeters and ellipsometers

High power single mode operation of long cavity GaAlAs lasers with nonabsorbing mirror buried twin ridge substrate structure

H. Naito, O. Imafuji, M. Kume, H. Shimizu, and M. Kazumura

Appl. Phys. Lett. 61, 515 (1992); http://dx.doi.org/10.1063/1.107872 (2 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
We have newly developed a 350 μm long cavity GaAlAs laser with nonabsorbing mirror buried twin ridge substrate structure, in order to obtain highly reliable high power single mode operation. It is found that the long cavity stabilizes lateral mode at powers higher than conventional maximum values because the carrier density is reduced to well suppress spatial hole‐burning effect. The fundamental spatial mode operation is confirmed up to 210 mW and the maximum output power as high as 380 mW is obtained. The lifetime at 100 and 200 mW at 25 °C are expected to be 170 000 and 24 000 h, respectively, from the aging test results.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation

Influence of carrier capture on the quantum efficiency of as‐etched and epitaxially buried In0.53Ga0.47As/InP quantum wires

G. Lehr, R. Bergmann, R. Rudeloff, F. Scholz, and H. Schweizer

Appl. Phys. Lett. 61, 517 (1992); http://dx.doi.org/10.1063/1.107873 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
Using electron beam lithography dry etching and an epitaxial regrowth step we have prepared buried In0.53Ga0.47As/InP quantum wires. Measurements of the quantum efficiency under different excitation energies reveal the strong impact of carrier loss processes in the barrier on the quantum efficiency of the wire structures. For epitaxially buried wires we find under resonant excitation nearly no decrease in the quantum efficiency down to a wire width of 65 nm. This gives evidence that the regrowth step strongly suppresses the nonradiative recombination at the boundaries of the active region of the wire. Furthermore the comparison of resonant and nonresonant excitation yields an improvement of the carrier capture due to epitaxial regrowth.
Show PACS
78.55.Cr III-V semiconductors
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Ultrafast chemical reactions between nickel and aluminum powders during shock loading

L. S. Bennett, F. Y. Sorrell, I. K. Simonsen, Y. Horie, and K. R. Iyer

Appl. Phys. Lett. 61, 520 (1992); http://dx.doi.org/10.1063/1.107874 (2 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
A recent investigation of powdered Ni‐Al systems subject to shock loading has yielded evidence that reactions occur during the shock front. Time‐resolved measurements of normal shock pressure indicate that an ‘‘excess pressure’’ is generated possibly due to an exothermic reaction in the Ni‐Al system. These reactions appear to occur during the 100 ns that represent the shock front. A clear reaction threshold is observed and corroborated by micrographs of the recovered samples.
Show PACS
62.50.-p High-pressure effects in solids and liquids

Fabrication of ultrathin metal oxide films using Langmuir–Blodgett deposition

D. T. Amm, D. J. Johnson, T. Laursen, and S. K. Gupta

Appl. Phys. Lett. 61, 522 (1992); http://dx.doi.org/10.1063/1.107875 (3 pages) | Cited 21 times

Full Text: | Download PDF

Show Abstract
Thin Y2O3 films have been fabricated using a Langmuir–Blodgett (LB) process. Uniform LB films of yttrium arachidate have been successfully deposited up to 200 layers. These films were found to decompose uniformly above 300 °C leaving a thin oxide layer. X‐ray diffraction, laser reflection, and Rutherford backscattering have been used to determine crystal structure and stoichiometry of the film before, during, and after thermal decomposition. This test system demonstrates the potential application of Langmuir–Blodgett deposition for inorganic oxide film fabrication of thicknesses ranging from 0.1 to 40 nm.
Show PACS
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Low resistance tungsten films on GaAs deposited by means of rapid thermal low pressure chemical vapor deposition

A. Katz, A. Feingold, S. Nakahara, S. J. Pearton, and E. Lane

Appl. Phys. Lett. 61, 525 (1992); http://dx.doi.org/10.1063/1.107876 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Low resistance tungsten (W) films were deposited onto GaAs substrates by means of rapid thermal low pressure chemical vapor deposition (RT‐LPCVD), using tungsten hexafluoride (WF6) gas reduced by hydrogen (H2). Deposition temperatures up to 550 °C for durations of up to 30 s were explored, resulting in deposition of relatively pure W films (containing less than 2% O2 and C). Post‐deposition sintering of the layers led to significant reduction of the resistivity to values as low as 50 μΩ cm. The efficiency of the deposition improved upon increasing the H2 flow rate up to 1250 sccm resulting in a deposition rate of about 10 nm/s at a total chamber pressure of 3.5 Torr and temperature of 500 °C. The films appeared to be polycrystalline with a very fine grain structure, regardless of the deposition temperature with good morphology and underwent a limited reaction with the underlying GaAs substrates.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Epitaxial growth and properties of YBa2Cu3Ox‐Pb(Zr0.6Ti0.4)O3‐YBa2Cu3Ox trilayer structure by laser ablation

Yu. A. Boikov, S. K. Esayan, Z. G. Ivanov, G. Brorsson, T. Claeson, J. Lee, and A. Safari

Appl. Phys. Lett. 61, 528 (1992); http://dx.doi.org/10.1063/1.107877 (3 pages) | Cited 26 times

Full Text: | Download PDF

Show Abstract
We have grown YBa2Cu3Ox‐Pb(Zr0.6Ti0.4)O3‐YBa2Cu3Ox multilayer structure on SrTiO3 and Al2O3 substrates using laser ablation. The deposition conditions for the growth of trilayers and their properties are studied in this investigation. Scanning electron microscope images and x‐ray diffraction analyses indicate that all the constituent films in the trilayer grow epitaxially on SrTiO3 and were highly oriented on Al2O3. Transport measurements on these multilayers show that top YBa2Cu3Ox films have good superconducting properties.
Show PACS
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.-a Thin film structure and morphology
74.70.-b Superconducting materials other than cuprates
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Improved dosimetry for metalorganic vapor phase epitaxy from a solution of trimethylindium

D. M. Frigo, G. P. M. van Mier, J. H. Wilkie, and A. W. Gal

Appl. Phys. Lett. 61, 531 (1992); http://dx.doi.org/10.1063/1.107878 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
A novel precursor system for metalorganic vapor phase epitaxy of indium‐containing layers, solid trimethylindium (TMI) partly dissolved in N, N‐dimethyldodecylamine, is described. Used in a conventional bubbler, the output concentration of TMI entrained by H2 carrier gas from this source was measured using an ultrasonic cell (Epison) and compared with that from a conventional TMI source. Initially the output stability from both sources was found to be virtually identical; after approximately 50% depletion the output from the solution source was substantially more stable. The solution source was used to deposit InP and lattice‐matched InGaAs/InP, with excellent optical and electrical properties (μ77=181 000 and 44 000 cm2/V s, respectively). With only 5 g solid TMI remaining, the continued stability of the solution source was shown by growing a lattice‐matched GaInAs/InP layer having an x‐ray diffraction peak of 26 arcsec.
Show PACS
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

Photoassisted metalorganic molecular beam epitaxy of ZnSe

C. A. Coronado, E. Ho, L. A. Kolodziejski, and C. A. Huber

Appl. Phys. Lett. 61, 534 (1992); http://dx.doi.org/10.1063/1.107879 (3 pages) | Cited 6 times

Full Text: | Download PDF

Show Abstract
Photoassisted heteroepitaxy of ZnSe on GaAs by metalorganic molecular beam epitaxy has been performed using sources of diethylselenium and diethylzinc. Illuminating the substrate during growth with an Ar ion laser has been observed to significantly enhance the growth rate. Growth rate enhancement was found to be a function of substrate temperature, VI/II gas flow ratio, and laser wavelength and intensity. Photons having energies sufficient to generate electron/hole pairs in the growing ZnSe film resulted in growth rate enhancement. The photoassisted growth has application for (i) increasing the anomalously low growth rate which is observed, (ii) assisting in tuning the surface stoichiometry, and (iii) providing for selective area epitaxy.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
82.50.-m Photochemistry

New method to improve the adhesion strength of tungsten thin film on silicon by W2N glue layer

Yong Tae Kim, Chang Woo Lee, and Suk‐Ki Min

Appl. Phys. Lett. 61, 537 (1992); http://dx.doi.org/10.1063/1.107880 (3 pages) | Cited 19 times

Full Text: | Download PDF

Show Abstract
When the partial pressure ratio of WF6:NH3:H2 is 2:1:50, (111) and (200) oriented tungsten nitride (W2N) thin films can be deposited by plasma enhanced chemical vapor deposition and the resistivity of as‐deposited films is 95–100 μm cm. In order to improve the adhesion of chemical vapor deposited tungsten (W) thin films, this W2N glue layer is interposed between W and Si. The acoustic emission‐load graphs obtained by the scratch test method show that the adhesion strengths of W films on the W2N glue layers are apparently improved from 1–2 to 9–11 N. The more adhesive contact can be attributed to the introduction of nitrogen interstitials because these nitrogen interstitials are expected to modify the structural properties such as porosity and vacancies in the W2N films.
Show PACS
68.60.Bs Mechanical and acoustical properties
68.55.Nq Composition and phase identification
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
85.40.Ls Metallization, contacts, interconnects; device isolation

Point defects in Si thin films grown by molecular beam epitaxy

H.‐J. Gossmann, P. Asoka‐Kumar, T. C. Leung, B. Nielsen, K. G. Lynn, F. C. Unterwald, and L. C. Feldman

Appl. Phys. Lett. 61, 540 (1992); http://dx.doi.org/10.1063/1.107881 (3 pages) | Cited 30 times

Full Text: | Download PDF

Show Abstract
Depth profiles of vacancylike defects have been determined by positron annihilation spectroscopy in 200‐nm‐thick Si films grown by molecular beam epitaxy on Si(100) substrates at growth temperatures Tgrowth=200–560 °C. The line shape of the radiation emitted from implanted positrons annihilating in the near‐surface region of a solid gives quantitative, depth‐resolved information on defect concentrations in a nondestructive way. In particular, the method is sensitive to vacancylike defects in a concentration range inaccessible to electron microscopy or ion scattering, but important for electrical device characteristics. The sensitivity limit for these defects in the present experiments is estimated as 5×1015 cm−3. Films grown at Tgrowth≥475±20 °C are indistinguishable from virgin wafers. So are samples with Tgrowth=220±20 °C, subjected to a 2 min, TRTA≳500 °C rapid thermal anneal (RTA) after every ≊30 nm of Si growth. If TRTA=450±20 °C, part of the film contains a concentration of vacancylike defects on the order of 1018 cm−3. Our results indicate the importance of the growth parameters, such as temperature and substrate preparation, for the production of high quality films.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
78.70.Bj Positron annihilation

Microwave resonators from YBa2Cu3O7−δ thin films made by plasma‐enhanced metalorganic chemical vapor deposition

K. H. Young, McD. Robinson, G. V. Negrete, J. Zhao, C. S. Chern, Y. Q. Li, and P. E. Norris

Appl. Phys. Lett. 61, 543 (1992); http://dx.doi.org/10.1063/1.107856 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Epitaxial YBa2Cu3O7−δ thin films on LaAlO3 deposited by plasma‐enhanced metalorganic chemical vapor deposition were tested in a 100 GHz microwave cavity and as patterned 5.6 GHz resonators. Two films, both having high critical temperature (≳90 K) and high critical current density (≳106 A/cm2), exhibited low‐power Q’s of 5400 and 8000 as 5.6 GHz microstrip resonators when operated at 77 K. The equivalent surface resistances at 10 GHz are 1.7 and 1 mΩ, respectively. Despite the fact that these films are thinner than typical laser ablation films, the results are within a factor of 2 of the best laser ablation prepared YBa2Cu3O7−δ films.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
74.25.N- Response to electromagnetic fields
74.70.-b Superconducting materials other than cuprates
74.78.-w Superconducting films and low-dimensional structures

Room temperature damage removal from InP by optical pumping

Hideo Nakanishi, Mitsuka Kanada, and Kazumi Wada

Appl. Phys. Lett. 61, 546 (1992); http://dx.doi.org/10.1063/1.107857 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
Removal of ion‐implantation‐induced damage in InP is observed to a considerable extent by optical pumping using argon ion laser irradiation at room temperature. The damage takes the form of recombination, scattering, and compensation centers, which were generated by Be implantation with dose of 1010–1012/cm2. We find that minority carrier injection by optical pumping is an attractive alternative to technologies based on a thermal annealing approach for the removal of these centers.
Show PACS
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.72.-y Defects and impurities in crystals; microstructure
85.40.Hp Lithography, masks and pattern transfer

Loading effect of quartz microwave window on SF6 plasma in an electron cyclotron resonance reactor

Andrew J. Watts and Walter J. Varhue

Appl. Phys. Lett. 61, 549 (1992); http://dx.doi.org/10.1063/1.107858 (2 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
The choice of dielectric material for use as a microwave window, or liner, in an electron cyclotron resonance reactor can affect the plasma conditions and process results. SF6 plasma characterization data were compared using a quartz window with and without an alumina cover plate. Both free fluorine and ion current density were suppressed when only the quartz window was used. The loading effect of the uncovered quartz window resulted in a reduced silicon etch rate at the downstream substrate position. The etch rate was further decreased by an SiO2 deposition at the substrate.
Show PACS
81.65.-b Surface treatments
52.75.-d Plasma devices
52.70.-m Plasma diagnostic techniques and instrumentation

Enhancement of Shubnikov–de Haas oscillations by carrier modulation

S. E. Schacham, E. J. Haugland, and S. A. Alterovitz

Appl. Phys. Lett. 61, 551 (1992); http://dx.doi.org/10.1063/1.107859 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
A drastic enhancement of the Shubnikov–de Haas (SdH) pattern is obtained by recording the changes in the quantum oscillations of magnetoresistance due to modulation of the carrier concentration. The technique enables measurement of the SdH waveform at relatively high temperatures and in samples with moderate mobilities. The modulated waveform shows selective enhancement of the low‐frequency SdH oscillations associated with the upper subband. Thus, we were able to record very clear oscillations generated by a carrier concentration well below 5×1010 cm−2. The theory for this selective enhancement is provided.
Show PACS
71.18.+y Fermi surface: calculations and measurements; effective mass, g factor
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Electrochemical capacitance‐voltage depth profiling of nanometer‐scale layers fabricated by Ga+ focused ion beam implantation into silicon

H. C. Mogul, A. J. Steckl, Gyles Webster, M. Pawlik, and S. Novak

Appl. Phys. Lett. 61, 554 (1992); http://dx.doi.org/10.1063/1.107860 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
The electrochemical capacitance‐voltage (ECV) profiling technique is employed to measure the active carrier concentration in nanoscale layers fabricated by focused ion beam (FIB) implantation of 3 to 10 keV Ga+ ions into crystalline Si. The carrier concentration profiles obtained by ECV indicate the ability of this technique to probe depths as shallow as 2–3 nm and with a nanometer‐scale depth resolution. The carrier concentration obtained by ECV matches well with the Ga atomic concentration profile detected by secondary‐ion mass spectroscopy, but is almost an order of magnitude higher than that provided by the spreading resistance profile technique.
Show PACS
61.72.uf Ge and Si
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Surface segregation of In atoms during molecular beam epitaxy and its influence on the energy levels in InGaAs/GaAs quantum wells

K. Muraki, S. Fukatsu, Y. Shiraki, and R. Ito

Appl. Phys. Lett. 61, 557 (1992); http://dx.doi.org/10.1063/1.107835 (3 pages) | Cited 192 times

Full Text: | Download PDF

Show Abstract
Surface segregation of In atoms during molecular beam epitaxy (MBE) and its influence on the energy levels in InGaAs/GaAs quantum wells (QWs) were systematically studied using secondary‐ion mass spectroscopy (SIMS) and photoluminescence (PL). Strong dependence of In surface segregation on the growth conditions was found; when the growth temperature was raised from 370 to 520 °C, the segregation length was observed to increase from 0.8 up to 2.9 nm, accompanied by an appreciable peak energy shift in the PL spectra of the InGaAs/GaAs QWs. The correlation between In surface segregation and the energy levels in InGaAs/GaAs QWs was clarified for the first time.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.55.Cr III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

Tm3+‐related emissions in III‐V semiconductors grown by metalorganic vapor phase epitaxy

K. Pressel, J. Weber, C. Hiller, D. Ottenwälder, W. Kürner, A. Dörnen, F. Scholz, K. Locke, D. Wiedmann, and F. Cordeddu

Appl. Phys. Lett. 61, 560 (1992); http://dx.doi.org/10.1063/1.107836 (3 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
Layers of InP:Tm, GaAs:Tm, GaP:Tm, and GaInP:Tm have been grown by metal‐organic vapor phase epitaxy at atmospheric pressure using tris(isopropylcyclopentadienyl)thulium as a liquid Tm source. Electrical measurements revealed no characteristic influence of Tm on the electrical properties of the semiconductor host. Tm3+‐related 4f emissions at 1.2 and 1.9 μm are observed both in GaAs and GaInP. In GaAs, the Tm3+ 4f luminescence at 1.2 μm consists of a series of very sharp lines. In GaInP samples, the Tm3+‐related luminescence at 1.2 μm is much stronger than in the GaAs samples and is still observable at room temperature.
Show PACS
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
78.30.-j Infrared and Raman spectra
78.40.Fy Semiconductors
71.55.Eq III-V semiconductors

Direct evidence for the amorphous silicon phase in visible photoluminescent porous silicon

J. M. Perez, J. Villalobos, P. McNeill, J. Prasad, R. Cheek, J. Kelber, J. P. Estrera, P. D. Stevens, and R. Glosser

Appl. Phys. Lett. 61, 563 (1992); http://dx.doi.org/10.1063/1.107837 (3 pages) | Cited 84 times

Full Text: | Download PDF

Show Abstract
We report on micro‐Raman spectroscopy studies of porous silicon which show an amorphous silicon Raman line at 480 R cm−1 from regions that emit visible photoluminescence. A Raman line corresponding to microcrystalline silicon at 510 R cm−1 is also observed. X‐ray photoelectron spectroscopy data is presented which shows a high silicon‐dioxide content in porous silicon consistent with an amorphous silicon phase.
Show PACS
78.30.-j Infrared and Raman spectra
81.65.-b Surface treatments
78.55.Hx Other solid inorganic materials

Influence of silicon on the properties of reactively sputtered hydrogenated amorphous germanium

T. Drüsedau and B. Schröder

Appl. Phys. Lett. 61, 566 (1992); http://dx.doi.org/10.1063/1.107838 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Hydrogenated amorphous germanium‐silicon films (a‐Ge1−xSix:H, 10−3<x<10−1) were prepared by reactive dc‐magnetron sputtering from a germanium target in an Ar/H2/SiH4 atmosphere. Silicon incorporation leads to a decrease of the dark conductivity σD (mainly independent of the hydrogen pressure) and a weaker decrease of the photoconductivity σph (strongly dependent on the hydrogen pressure) and has no influence on the gap state density detected by photothermal deflection spectroscopy. The best photoconductivity corresponding to μτ=10−5 cm2/V was obtained under the highest hydrogen pressure and is not influenced by silicon up to x=0.01. The ratio of σph/σD under monochromatic excitation (632 nm, 9 mW/cm2) increases from 0.25 in a‐Ge:H to more than 1 in a‐Ge0.99Si0.01:H.
Show PACS
73.50.Pz Photoconduction and photovoltaic effects
73.61.Cw Elemental semiconductors
73.61.Jc Amorphous semiconductors; glasses
73.61.Le Other inorganic semiconductors
81.15.Cd Deposition by sputtering

Thermal wave measurement of ion implanted semiconductors in the mirage effect geometry

A. L. Glazov, K. L. Muratikov, and A. V. Suvorov

Appl. Phys. Lett. 61, 569 (1992); http://dx.doi.org/10.1063/1.107839 (3 pages)

Full Text: | Download PDF

Show Abstract
The effect of ion implant processes on an amplitude and phase of thermal wave signals from semiconductors was analyzed. It is experimentally shown for InP and GaAs that the ion implantation results in a considerable increase of the signal amplitude when using Nd:YAG pump laser at 1.06 μm wavelength. It was found out that the nature of spatial oscillations observed in a signal behavior is forced by pump radiation interference due to the internal reflection from a rear sample surface.
Show PACS
61.72.U- Doping and impurity implantation
62.65.+k Acoustical properties of solids
61.72.Yx Interaction between different crystal defects; gettering effect

Characterization of InxGa1−xAs/GaAs strained‐layer superlattices by transmission electron microscopy and convergent beam electron diffraction

X. L. Wei, K. K. Fung, W. Feng, and J. M. Zhou

Appl. Phys. Lett. 61, 572 (1992); http://dx.doi.org/10.1063/1.107840 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
Four InxGa1−xAs/GaAs strained‐layer superlattices grown by molecular beam epitaxy have been studied by transmission electron microscopy (TEM) and convergent beam electron diffraction (CBED). Cross‐section TEM images show that the interfaces are sharp and the superlattice layers are uniform. Misfit dislocations are also observed at the superlattice substrate interface. Diffraction disks of reflections in plan‐view CBED patterns show the presence of satellite sidebands due to periodic modulations of the superlattices. The separation and intensities of the sidebands depend sensitively on the structural parameters of the superlattices. Accurate values of the elastic strains and thicknesses of the superlattice layers have been obtained by matching the observed and kinematically calculated sideband intensities based on a square wave model of the strain profile in the superlattice.
Show PACS
68.55.-a Thin film structure and morphology
07.79.Cz Scanning tunneling microscopes
61.05.-a Techniques for structure determination
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close