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

27 Nov 1995

Volume 67, Issue 22, pp. 3227-3357

Page 1 of 2 Pages Next Page | Jump to Page

Laser‐induced stresses versus mechanical stress power measurements during laser ablation of solids

Mark A. Shannon and Richard E. Russo

Appl. Phys. Lett. 67, 3227 (1995); http://dx.doi.org/10.1063/1.114880 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
Laser‐induced stresses resulting from high‐power laser‐material interactions have been studied extensively. However, the rate of change in mechanical energy, or stress power, due to laser‐induced stresses has only recently been investigated. An unanswered question for monitoring laser‐material interactions in the far‐field is whether stress power differs from stresses measured, particularly with respect to laser‐energy coupling to a solid target. This letter shows experimental acoustic data which demonstrate that stress power measured in the far field of the target shows changes in laser‐energy coupling, whereas the stresses measured do not. For the ambient medium above the target, stress power and stress together reflect changes in laser‐energy coupling. © 1995 American Institute of Physics.
Show PACS
62.50.-p High-pressure effects in solids and liquids
65.40.De Thermal expansion; thermomechanical effects
79.20.Ds Laser-beam impact phenomena

Power penalty due to timing jitter for lasers modulated without prebias

N. K. Dutta

Appl. Phys. Lett. 67, 3230 (1995); http://dx.doi.org/10.1063/1.114881 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
For lasers modulated with a pseudorandom bit stream without prebias, the delay between the optical pulse and the current pulse depends on the number of ‘‘0’’s preceding the current pulse (‘‘1’’). Since 1’s and 0’s occur randomly in a pseudorandom bit stream and the decision circuit is designed to start sampling at a given time, this effect results in a timing jitter. The jitter induced noise and the associated power penalty are calculated. The results suggest that the ratio of the modulation current to the threshold current of the laser should be ≳25 to keep the power penalty below 1 dB at high data rates. Low threshold lasers operating without prebias are important for laser array based transmitters. © 1995 American Institute of Physics.  
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Fc Modulation, tuning, and mode locking
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Electrical and optical characteristics of AlAsSb/GaAsSb distributed Bragg reflectors for surface emitting lasers

O. Blum, M. J. Hafich, J. F. Klem, K. L. Lear, and S. N. G. Chu

Appl. Phys. Lett. 67, 3233 (1995); http://dx.doi.org/10.1063/1.114882 (3 pages) | Cited 13 times

Full Text: | Download PDF

Show Abstract
We demonstrate an undoped 20 1/2 pair AlAsSb/GaAsSb distributed Bragg reflector (DBR) grown lattice matched to an InP substrate by molecular beam epitaxy. Reflectivity measurements indicate a stop band centered at 1.78 μm with a maximum reflectivity exceeding 99%. We also measure current–voltage characteristics in a similar 10 1/2 period p‐type DBR and find that a current density of 1 kA/cm2 produces a 2.5 V drop. Hole mobilities and doping concentrations in AlAsSb and GaAsSb are also reported. © 1995 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.79.Bh Lenses, prisms and mirrors
78.66.Fd III-V semiconductors

Ultrafast gain‐switching dynamics in 1.5 μm dynamical single‐mode semiconductor lasers: 50–130 GHz high frequency self‐pulsations

Jian Wang, Heinz Schweizer, Janez Kovač, Christiane Kaden, E. Zielinski, M. Klenk, and R. Weinmann

Appl. Phys. Lett. 67, 3236 (1995); http://dx.doi.org/10.1063/1.114883 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
In this letter generation of up to 130 GHz high frequency self‐pulsation in ultrafast gain‐switched InGaAs/InGaAsP dynamical single‐mode lasers with monolithically integrated external cavities is reported. With various active cavity lengths and external cavity lengths, the dependence of the pulsation frequency on the length of the respective cavity is shown and analyzed in detail for a pulsation frequency range from 50 to 130 GHz. Theoretically, by treating the external cavity as a gain‐switched laser amplifier and taking into account the coherent time‐dependent amplification, shortening and reflection of an incident picosecond optical pulse in the gain‐switched amplifier, we can well understand and simulate the observed high frequency self‐pulsations. © 1995 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers

Generation and tuning of second harmonic radiation produced by ultrashort dye laser pulses from a gold surface

S. D. Moustaïzis, N. A. Papadogiannis, C. Fotakis, Gy. Farkas, and Cs. Tóth

Appl. Phys. Lett. 67, 3239 (1995); http://dx.doi.org/10.1063/1.114884 (3 pages) | Cited 1 time

Full Text: | Download PDF

Show Abstract
Tunable second harmonic radiation has been generated on a gold surface by means of a dye laser system capable of emitting pulses of 450 fs and 4.5 ps duration. The intensity of harmonic radiation was maximum along the direction of the reflected incident laser beam, when the polarization direction of the incoming radiation was vertical to the target surface (p polarization). The efficiency for second harmonic generation was found to depend strongly on the pulse duration of the laser beam. The observed change of the harmonic generation efficiency as a function of the angle of incidence and the pulse duration of the laser beam suggests that, due to coherence effects, the actual overlapping spatial dimension of the interaction region between the laser pulse and the electron gas of the metallic surface plays an important role. © 1995 American Institute of Physics.
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Nonlinear self‐channeling of a laser beam at the surface of a photorefractive fiber

A. A. Kamshilin, E. Raita, V. V. Prokofiev, and T. Jaaskelainen

Appl. Phys. Lett. 67, 3242 (1995); http://dx.doi.org/10.1063/1.114885 (3 pages) | Cited 11 times

Full Text: | Download PDF

Show Abstract
We experimentally observed the self‐channeling of the light beam in photorefractive Bi12TiO20 fiberlike sample owing to the strong fanning effect. It results in significant speed up of the photorefractive response time in waveguides and in anomalous dependence of the response time on the applied ac electric field amplitude: the higher electric field, the faster response. © 1995 American Institute of Physics.
Show PACS
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
42.81.Dp Propagation, scattering, and losses; solitons

Suppression of self‐pulsation for tens of gigahertz optical pulses from passively mode‐locked semiconductor lasers

J. Yu and D. Bimberg

Appl. Phys. Lett. 67, 3245 (1995); http://dx.doi.org/10.1063/1.114886 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
43 GHz repetition rate Fourier transform‐limited light pulses of a width of 1.5 ps are achieved by passively mode‐locking an ion‐implanted semiconductor laser in a very short external cavity. A higher repetition rate is limited by strongly mixed self‐pulsation. A numerical investigation of passive model‐locking is carried out based on the solution of traveling wave rate equations of an external cavity semiconductor laser. We find that the gain nonlinearity factor can significantly influence the present range of the mixed self‐pulsation. With the increase of the nonlinearity factor, the operation tends to pure passive mode‐locking at a low injection current. In addition, the proper adjustment of the ratio of differential absorption to differential gain and the carrier lifetime in the absorber can reduce the necessary current for pure passive mode‐locking. © 1995 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Fc Modulation, tuning, and mode locking

A sensitive ultrasonic method for measuring transient motions of a surface

D. Royer and O. Casula

Appl. Phys. Lett. 67, 3248 (1995); http://dx.doi.org/10.1063/1.114887 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
A method for measuring surface displacements is described. The principle is based on the detection of the phase shift of a high frequency continuous ultrasonic wave reflected from the moving surface. The analysis shows that the long time delay undergone by the ultrasonic wave produces a significant enhancement of the Doppler phase shift signal. Experiments were carried out in water with a 30‐MHz focused transducer probe and transient mechanical displacements smaller than 1 Å (surface velocities smaller than 1 mm/s) were detected in a 10 MHz bandwidth. © 1995 American Institute of Physics.
Show PACS
07.64.+z Acoustic instruments and equipment
43.30.Es Velocity, attenuation, refraction, and diffraction in water, Doppler effect
43.38.-p Transduction; acoustical devices for the generation and reproduction of sound
43.60.Rw Remote sensing methods, acoustic tomography

Heterodyne detection of ultrasound from rough surfaces using a double phase conjugate mirror

Philippe Delaye, Alain Blouin, Denis Drolet, and Jean‐Pierre Monchalin

Appl. Phys. Lett. 67, 3251 (1995); http://dx.doi.org/10.1063/1.114888 (3 pages) | Cited 11 times

Full Text: | Download PDF

Show Abstract
We present an improved version of the classical heterodyne interferometer for ultrasound detection, which includes a double phase conjugate mirror (DPCM) in the detection arm. The DPCM performs wave front adaptation to plane wave of the speckled beam scattered by the rough surface of the sample. The performances of the system are analyzed regarding the transmission (≊30%) and fidelity (≊70%) of the phase conjugation and the response time and étendue of the device. An example of application to the detection of laser generated ultrasound is also presented.
Show PACS
43.35.Sx Acoustooptical effects, optoacoustics, acoustical visualization, acoustical microscopy, and acoustical holography
43.35.Yb Ultrasonic instrumentation and measurement techniques

Interactions between neighboring beams in a heavy ion fusion reactor chamber

Debra A. Callahan

Appl. Phys. Lett. 67, 3254 (1995); http://dx.doi.org/10.1063/1.114889 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
Multiple beams in a heavy ion fusion reactor chamber can increase the beam spot size at the target. Each beam experiences the field from nearby beams and this field varies along the bunch length. These field variations cause different parts of the beam to be focused at different locations and results in a larger spot size at the target. Calculations show that this is not a large effect for a beam generated by an induction linear accelerator in which the current is nearly constant over much of the pulse. These calculations show 90%–99% of the charge reaches the target for a radiation converter radius that is 10%–20% larger than the beam radius. © 1995 American Institute of Physics.
Show PACS
28.52.-s Fusion reactors
41.85.Ja Particle beam transport
52.58.Hm Heavy-ion inertial confinement

Observation of a single photoluminescence peak from a single quantum dot

Y. Nagamune, H. Watabe, M. Nishioka, and Y. Arakawa

Appl. Phys. Lett. 67, 3257 (1995); http://dx.doi.org/10.1063/1.114890 (3 pages) | Cited 23 times

Full Text: | Download PDF

Show Abstract
We observed a very sharp photoluminescence peak from a single GaAs/AlGaAs quantum dot structure by using a microphotoluminescence measurement technique. The spectral linewidth was more suppressed by decreasing the excitation laser power, which is mainly due to reduction of the filling effect of quantized energy levels. The minimal spectral linewidth with low excitation laser power was 0.9 meV. © 1995 American Institute of Physics.
Show PACS
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

The viscosity of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass forming alloy in the supercooled liquid

E. Bakke, R. Busch, and W. L. Johnson

Appl. Phys. Lett. 67, 3260 (1995); http://dx.doi.org/10.1063/1.114891 (3 pages) | Cited 82 times

Full Text: | Download PDF

Show Abstract
The viscosity of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass forming alloy in the supercooled liquid was measured using parallel plate rheometry. The measurements were carried out with different heating rates between 0.0167 and 1.167 K/s as well as isothermally. Because of the high thermal stability above the glass transition of this bulk metallic glass former with respect to crystallization, it was possible to measure viscosities in the range from 1010 to 106 poise. This region of viscosities has not been previously measured for supercooled metallic melts. Our measurements suggest that the viscosity of the supercooled liquid of this bulk glass former exhibits a small Vogel–Fulcher temperature relative to the glass transition temperature, similar to silicate glasses. © 1995 American Institute of Physics.
Show PACS
64.70.P- Glass transitions of specific systems
64.70.Q- Theory and modeling of the glass transition
66.20.-d Viscosity of liquids; diffusive momentum transport

Role of oxygen on the dangling bond configuration of low oxygen content SiNx:H films deposited at room temperature

S. Garcia, D. Bravo, M. Fernandez, I. Martil, and F. J. López

Appl. Phys. Lett. 67, 3263 (1995); http://dx.doi.org/10.1063/1.114892 (3 pages) | Cited 8 times

Full Text: | Download PDF

Show Abstract
SiNx:H films with a wide composition range and, some of them, with low oxygen content are deposited at room temperature. The defects observed in the films are attributed to Si‐dangling bonds, with a structure depending on film composition. For the N‐rich films they are of the form ⋅Si≡(N3), whereas for the films with similar [N]/[Si] ratio but containing oxygen, the predominant defect is proposed to be ⋅Si≡(Si2O), despite of the high N content and the low O content of these films. The spin density of the films has been related to the bonds that hydrogen establishes (either Si–H or N–H), with the maximum value corresponding to the minimum hydrogen content. Both maximum and minimum values, respectively, are obtained at the silicon percolation limit of the Si–Si bonds into the SiNx:H network, x∼1.10. © 1995 American Institute of Physics.
Show PACS
61.72.-y Defects and impurities in crystals; microstructure
75.20.Ck Nonmetals
78.66.Nk Insulators

A simple calibration method for potassium halide thermoluminescence dosimeters

L. P. Pashchenko, R. Pérez Salas, R. Aceves, and M. Barboza‐Flores

Appl. Phys. Lett. 67, 3266 (1995); http://dx.doi.org/10.1063/1.114893 (3 pages) | Cited 2 times

Full Text: | Download PDF

Show Abstract
We present a simple calibration method for europium‐doped potassium halide dosimeters. The procedure is based on the self‐irradiation absorbed dose of potassium halide thermoluminescence dosimeters due to the natural content of the radionuclide 40K in potassium halide crystals. In the small dose range of the order of 0.5 mGy, the precision of the proposed method is highly competitive with traditional calibration methods, without the need of artificial radiation sources and rather expensive and sophisticated measurement equipment. © 1995 American Institute of Physics.
Show PACS
07.77.Ka Charged-particle beam sources and detectors
29.40.Wk Solid-state detectors
78.60.Kn Thermoluminescence

Hydrogen and nitrogen bonding in silicon nitride layers deposited by laser reactive ablation: Infrared and x‐ray photoelectron study

A. Fejfar, J. Zemek, and M. Trchová

Appl. Phys. Lett. 67, 3269 (1995); http://dx.doi.org/10.1063/1.114894 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
Silicon nitride layers deposited by an excimer laser reactive ablation of silicon target in ammonia on Si(100) wafers kept at 300 or 600 °C have been studied by infrared absorption and angular resolved x‐ray photoelectron spectroscopy. Presence of hydrogen in the deposits unexpected at the high substrate temperatures is documented. The observed deposit thicknesses, stoichiometry, and the hydrogen content as a function of ammonia pressure suggest a picture of the deposition process with Si3N4 synthesis taking place on the growing deposit surface, contrary to the liquid phase reaction model suggested for analogous TiN deposition. © 1995 American Institute of Physics.
Show PACS
68.35.B- Structure of clean surfaces (and surface reconstruction)
81.15.Fg Pulsed laser ablation deposition

Step flow growth of (La,Ca)MnOδ thin films on (110)NdGaO3

X. T. Zeng, H. K. Wong, J. B. Xu, and I. H. Wilson

Appl. Phys. Lett. 67, 3272 (1995); http://dx.doi.org/10.1063/1.114895 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
Step flow growth patterns have been observed on single‐crystal (La,Ca)MnOδ (LCMO) thin films by atomic force microscopy. These films were grown on (110) NdGaO3 substrates by a simple facing‐target sputtering method. The steps, of monolayer height (0.2 nm), are surprisingly straight and evenly spaced. The best sample has an average step width of about 400 nm which is comparable to that found on the molecular beam epitaxially grown GaAs. The step edges are parallel to the LCMO [001] direction indicating that the growth rates are anisotropic. © 1995 American Institute of Physics.  
Show PACS
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy
68.55.-a Thin film structure and morphology
81.15.Cd Deposition by sputtering

Direct bonding of piezoelectric crystal onto silicon

Akihiko Namba, Masato Sugimoto, Tetsuyoshi Ogura, Yoshihiro Tomita, and Kazuo Eda

Appl. Phys. Lett. 67, 3275 (1995); http://dx.doi.org/10.1063/1.114896 (2 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
A method for bonding a piezoelectric crystal directly onto silicon, without any bonding agents, is reported. The interface microstructure, procedures of fabricating a lithium tantalate (LiTaO3☒‐ on‐silicon resonator, and its resonant characteristics are described. This technique is very promising for miniaturizing electroacoustic integrated devices. © 1995 American Institute of Physics.
Show PACS
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
85.50.-n Dielectric, ferroelectric, and piezoelectric devices

New electron irradiation induced electron trap in epitaxially grown Si‐doped n‐GaAs

F. Danie Auret, Stewart A. Goodman, and Walter E. Meyer

Appl. Phys. Lett. 67, 3277 (1995); http://dx.doi.org/10.1063/1.115219 (3 pages) | Cited 5 times

Full Text: | Download PDF

Show Abstract
The defects induced by electron irradiation in epitaxially grown Si‐doped n‐GaAs were investigated by deep level transient spectroscopy. In addition to observing the well‐known E1–E3 radiation induced defects, we detected another electron trap, Eβ3, with electronic properties, although similar to those of E3, not identical. Eβ3 is metastable and thus its energy level can be reproducibly removed by hole injection at 90–130 K and reintroduced by annealing above 160 K. We could induce Eβ3 by electron irradiation in Si‐doped GaAs, but not in undoped GaAs. © 1995 American Institute of Physics.
Show PACS
61.80.Fe Electron and positron radiation effects
71.55.Eq III-V semiconductors

Controlled photon emission in porous silicon microcavities

Lorenzo Pavesi, Claudio Mazzoleni, Alessandro Tredicucci, and Vittorio Pellegrini

Appl. Phys. Lett. 67, 3280 (1995); http://dx.doi.org/10.1063/1.115220 (3 pages) | Cited 61 times

Full Text: | Download PDF

Show Abstract
We demonstrate the preparation of narrow‐band porous‐silicon reflectors integrated on porous‐silicon layers by electrochemical etching. By carefully tuning the resulting photon cavity mode around the maximum of the porous silicon photoluminescence, we have obtained both a narrowing and enhancement of the emission line, and a highly concentrated radiation pattern. These results show that the porous silicon spontaneous emission is modified because of the coupling with the photon cavity mode. © 1995 American Institute of Physics.
Show PACS
78.55.Hx Other solid inorganic materials

Improvement in electrical properties of buried SiO2 layers by high‐temperature oxidation

B. J. Mrstik, P. J. McMarr, H. L. Hughes, M. J. Anc, and W. A. Krull

Appl. Phys. Lett. 67, 3283 (1995); http://dx.doi.org/10.1063/1.115221 (3 pages) | Cited 9 times

Full Text: | Download PDF

Show Abstract
The density of defects in the buried oxide of implanted oxide silicon‐on‐insulator material which cause low resistance paths between the substrate and top silicon layer has been greatly reduced by high temperature oxidation. The mechanism for this is the diffusion of oxygen through the top silicon layer to the buried oxide, where it oxidizes chains of silicon atoms. © 1995 American Institute of Physics.
Show PACS
61.80.Jh Ion radiation effects
73.61.Ng Insulators
81.65.-b Surface treatments

Thickness profiles of SiO2 films deposited from tetraethoxysilane/O3 precursors in ultra‐high‐aspect‐ratio capillaries

R. J. Soave, S. Ganguli, W. N. Gill, Y. Shacham‐Diamand, and J. W. Mayer

Appl. Phys. Lett. 67, 3286 (1995); http://dx.doi.org/10.1063/1.115222 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Thickness profiles of silicon dioxide films deposited by ozone‐augmented tetraethoxysilane have been experimentally measured in ultra‐high‐aspect ratio capillaries. The deposition profiles exhibit a sharp drop in film thickness near the capillary entrance followed by a gradual decrease in thickness along the capillary. A feature‐scale model for this process has been developed which includes the effect of by‐products on the reaction kinetics and transport inside the structure. Simulated deposition profiles agree well with the experimental data, indicating that a trapped by‐product inside the capillary inhibits the film‐forming reaction, thus producing the characteristic film profile. © 1995 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Reactive ion beam etching of aluminum indium antimonide, gallium indium antimonide heterostructures in electron cyclotron resonance methane/hydrogen/nitrogen/silicon tetrachloride discharges at room temperature

J. R. Sendra, J. Anguita, J. J. Pérez‐Camacho, and F. Briones

Appl. Phys. Lett. 67, 3289 (1995); http://dx.doi.org/10.1063/1.115223 (3 pages) | Cited 3 times

Full Text: | Download PDF

Show Abstract
Reactive ion beam etching of aluminum indium antimonide, gallium indium antimonide heterostructures in electron cyclotron resonance plasma using methane/hydrogen/nitrogen/silicon tetrachloride (CH4/H2/N2/SiCl4) mixtures has been performed at room temperature. Due to the ratio of chlorine to methane, formation of an indium chloride layer on the etched surface is avoided, thus resulting, in etched surfaces as smooth as the original ones and flat mesa sidewalls. Infrared diodes (2.3μm) have been fabricated using this etching technology. © 1995 American Institute of Physics.
Show PACS
81.65.-b Surface treatments

Delayed photocurrent affected by Γ‐X resonance in GaAs/AlAs type‐I short‐period superlattices

H. Mimura, N. Ohtani, M. Hosoda, K. Tominaga, T. Watanabe, G. Tanaka, and K. Fujiwara

Appl. Phys. Lett. 67, 3292 (1995); http://dx.doi.org/10.1063/1.115224 (3 pages) | Cited 7 times

Full Text: | Download PDF

Show Abstract
Delayed photocurrents were observed in GaAs/AlAs type‐I short‐period superlattices by measuring time‐resolved photoresponses under ultrashort optical pulse excitation. According to the envelope function calculations, the X1 state in AlAs barriers resonates with the Γ2 state in the adjacent GaAs wells at a bias voltage where the delayed photocurrents were conspicuous. These results strongly suggest that the dynamic carrier transport process is significantly influenced by X1‐Γ2 resonance effects in the superlattices. © 1995 American Institute of Physics.
Show PACS
73.50.Pz Photoconduction and photovoltaic effects
78.47.-p Spectroscopy of solid state dynamics

Acceptor‐bound exciton recombination dynamics in p‐type GaN

M. Smith, G. D. Chen, J. Y. Lin, H. X. Jiang, M. Asif Khan, and C. J. Sun

Appl. Phys. Lett. 67, 3295 (1995); http://dx.doi.org/10.1063/1.115225 (3 pages) | Cited 17 times

Full Text: | Download PDF

Show Abstract
Dynamics of the neutral‐acceptor‐bound exciton transition (the I1 line) in a Mg doped p‐type GaN epitaxial layer grown by metalorganic chemical vapor deposition (MOCVD) have been studied by time‐resolved photoluminescence emission spectroscopy. Two emission lines in the I1 transition region have been resolved in the time‐resolved spectra, possibly due to the existence of two energy states of the Mg impurities after postgrowth thermal annealing. The recombination lifetimes of the acceptor‐bound exciton transition have been measured under different conditions including temperature, excitation intensity, and emission energy. From these measurements, a value of about 450 ps for the radiative recombination lifetime has been obtained, which is an important physical quantity for optoelectronic device applications based on GaN. © 1995 American Institute of Physics.
Show PACS
78.47.-p Spectroscopy of solid state dynamics
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

Dependence of the density and type of stacking faults on the surface treatment of the substrate and growth mode in ZnSxSe1−x/ZnSe buffer layer/GaAs heterostructures

L. H. Kuo, L. Salamanca‐Riba, B. J. Wu, G. Hofler, J. M. DePuydt, and H. Cheng

Appl. Phys. Lett. 67, 3298 (1995); http://dx.doi.org/10.1063/1.115226 (3 pages) | Cited 41 times

Full Text: | Download PDF

Show Abstract
A systematic dependence of the density and type of stacking fault defects with substrate surface chemistry and film growth mode was observed in ZnSe‐based films grown on GaAs substrates. Namely, the density of Frank‐type stacking faults is very large for films grown on Ga‐rich surfaces, but is very low for films grown on As‐stabilized surfaces exposed to Zn prior to the growth of the film. In contrast, the density of Shockley‐type stacking faults increases for films grown by 3D growth mode at the initial stages of growth, but decreases greatly if the films are grown by the layer‐by‐layer growth mode. Films with stacking fault densities as low as 104/cm2 were obtained by growing the films by the layer‐by‐layer growth on GaAs epilayers with As‐stabilized surfaces that were exposed to Zn for 1–2 min prior to the growth of the films. © 1995 American Institute of Physics. [S0003‐6951(95)00548‐6]
Show PACS
68.55.-a Thin film structure and morphology
Page 1 of 2 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close