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15 Feb 1988

Volume 52, Issue 7, pp. 519-594

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Measurement of ultrashort optical pulses with β‐BaB2O4

K. L. Cheng, W. Bosenberg, F. W. Wise, I. A. Walmsley, and C. L. Tang

Appl. Phys. Lett. 52, 519 (1988); http://dx.doi.org/10.1063/1.99648 (3 pages) | Cited 13 times

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We have evaluated barium metaborate ( β‐BaB2O4) for its use in the measurement of ultrashort optical pulses. Using crystals grown in our laboratory, we have found that pulses as short as 50 fs can be measured accurately with a crystal 1.8 mm thick. The advantages of using barium metaborate rather than potassium dihydrogen phosphate (KDP) or ammonium dihydrogen phosphate (ADP) for autocorrelation measurements are discussed.
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42.65.Re Ultrafast processes; optical pulse generation and pulse compression

Carbon‐doped AlxGa1−xAs‐GaAs quantum well lasers

L. J. Guido, G. S. Jackson, D. C. Hall, W. E. Plano, and N. Holonyak

Appl. Phys. Lett. 52, 522 (1988); http://dx.doi.org/10.1063/1.99403 (3 pages) | Cited 27 times

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Data are presented demonstrating that carbon (C) can be used as the active p‐type dopant in high‐quality AlxGa1−xAs‐GaAs quantum well laser crystals. We show, by fabricating three different types of stripe geometry laser diodes (oxide stripe, hydrogenated stripe, and impurity‐induced layer‐disordered stripe), that C is a stable dopant and compatible in behavior with typical integrated‐circuit style of device processing. The data suggest that more complicated laser geometries are possible on C‐doped material because of minimal pattern ‘‘undercutting’’ after processing by, for example, hydrogenation or impurity‐induced layer disordering.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Nanosecond laser amplification via degenerate multiwave mixing in silicon

I. C. Khoo and R. Normandin

Appl. Phys. Lett. 52, 525 (1988); http://dx.doi.org/10.1063/1.99404 (3 pages) | Cited 4 times

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We present the results of a detailed study of degenerate multiwave mixing mediated nanosecond 1.06 μm pulse amplification in silicon, taking into account higher order diffracted beams, self‐phase modulation, pump depletions, intensity‐dependent absorption losses, electron‐hole plasma attenuation, and other geometrical optical parameters. Excellent agreements between theory and experiment are obtained.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation

GaAs surface emitting lasers with circular buried heterostructure grown by metalorganic chemical vapor deposition and two‐dimensional laser array

Fumio Koyama, Kazuhiko Tomomatsu, and Kenichi Iga

Appl. Phys. Lett. 52, 528 (1988); http://dx.doi.org/10.1063/1.99405 (2 pages) | Cited 16 times

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A metalorganic chemical vapor deposition (MOCVD) was used to grow both double‐heterostructure wafers and circular buried heterostructures for GaAlAs/GaAs surface emitting lasers. A vertical microcavity was formed with a diameter of 10 μm and a cavity length of 6 μm by a two‐step MOCVD growth and fully monolithic technology. Threshold currents under room‐temperature pulsed conditions ranged from 50 to 100 mA with a minimum of 50 mA. cw operation up to 160 K was obtained. In addition, a densely packed 5×5 SE laser array with 20 μm separation was demonstrated with a minimum threshold of 600 mA.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes

Unstable resonator with phase‐unifying coupler for high‐power lasers

Koji Yasui, Masaaki Tanaka, and Shigenori Yagi

Appl. Phys. Lett. 52, 530 (1988); http://dx.doi.org/10.1063/1.99406 (2 pages) | Cited 9 times

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A novel unstable resonator with a phase‐unifying output coupler has been developed. The output coupler structured with a partial‐reflection region in its center surrounded by an antireflection region unifies the phases of laser beams passing through these regions. Thus, a near‐Gaussian far‐field pattern beam has been obtained with a divergence full‐angle of 1.08 mrad on the application to a high‐power cw CO2 laser.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.55.Mv Dye lasers

Observation of a change in the form of polarization reversal in a vinylidene fluoride/trifluoroethylene copolymer

I. L. Guy and J. Unsworth

Appl. Phys. Lett. 52, 532 (1988); http://dx.doi.org/10.1063/1.99407 (3 pages) | Cited 15 times

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Polarization reversal in the ferroelectric polymer PVF2 is known to involve chains rotating in 60° steps. In a 75/25 mol % VF2/VF3 copolymer, chains rotate by two different mechanisms involving either 60° or 180° steps. The extent to which the 180° process contributes to the total polarization reversal is increased by poling.
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77.22.Ej Polarization and depolarization
77.80.-e Ferroelectricity and antiferroelectricity
61.41.+e Polymers, elastomers, and plastics

Quench rate enhancement in pulsed laser melting of Si by processing under water

A. Polman, W. Sinke, F. W. Saris, M. J. Uttormark, and Michael O. Thompson

Appl. Phys. Lett. 52, 535 (1988); http://dx.doi.org/10.1063/1.99408 (3 pages) | Cited 1 time

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The thermal quench rate during pulsed laser heating of Si can be enhanced by immersing the sample in a liquid (e.g., water) during irradiation. The liquid in contact with the irradiated surface acts as an additional heat sink increasing the thermal quench rate. The heat transfer processes and phase transformations were studied in real time using transient optical reflectance and electrical conductance techniques. Measurements of the melting and solidification dynamics of the Si reveal that the quench rate may be enhanced by 30% for deep melts. The measurements also indicate that a steam or superheated water phase is formed near the Si surface during the laser pulse. The observed phenomena are analyzed in terms of standard heat flow.
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81.40.Gh Other heat and thermomechanical treatments
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
64.70.D- Solid-liquid transitions
81.30.Fb Solidification

Observation of luminescence quenching dislocations in mercuric iodide by cathodoluminescence in a scanning electron microscope

T. W. James and Frederick Milstein

Appl. Phys. Lett. 52, 538 (1988); http://dx.doi.org/10.1063/1.99409 (2 pages) | Cited 5 times

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Cathodoluminescence images of ingrown and deformation‐induced dislocations were observed in single crystals of mercuric iodide that were vapor grown for the fabrication of radiation detectors. The imaging was done at 80 K in a scanning electron microscope.
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61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
62.20.F- Deformation and plasticity
78.60.Hk Cathodoluminescence, ionoluminescence
85.60.Gz Photodetectors (including infrared and CCD detectors)

Schottky and field‐effect transistor fabrication on InP and GaInAs

S. Loualiche, H. L’Haridon, A. Le Corre, D. Lecrosnier, M. Salvi, and P. N. Favennec

Appl. Phys. Lett. 52, 540 (1988); http://dx.doi.org/10.1063/1.99410 (3 pages) | Cited 20 times

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Schottky contacts with barrier heights of 0.76 eV on n‐type InP and 0.65 eV on n‐type GaInAs are realized by a new surface treatment. These contacts are used as a gate for the fabrication of field‐effect transistors (FET) on these materials. Extrinsic transconductances of 100 and 7.5 mS/mm are measured on GaInAs and InP FET’s, respectively. These values are obtained without optimization of the ohmic contacts of the devices and without a gate recess.
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85.30.Hi Surface barrier, boundary, and point contact devices
85.30.Tv Field effect devices
73.30.+y Surface double layers, Schottky barriers, and work functions
81.65.-b Surface treatments

Dislocation‐free GaAs epitaxial growth with the use of modulation‐doped AlAs‐GaAs superlattice buffer layers

Masanori Shinohara

Appl. Phys. Lett. 52, 543 (1988); http://dx.doi.org/10.1063/1.99411 (3 pages) | Cited 14 times

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Suppression of dislocation threading from the substrate into GaAs epitaxial layers is investigated by using AlAs‐GaAs superlattice buffer layers grown by molecular beam epitaxial technique. The efficiency of suppression is compared among several types of AlAs‐GaAs superlattices with different electrically active impurity‐doping distributions. With the use of modulation‐doped AlAs(Si)‐GaAs superlattice, dislocation threading is almost perfectly suppressed, and consequently, a dislocation‐free epilayer can be grown. Dislocation bending at the AlAs/GaAs interface is thought to be due to the interaction between dislocations and electric charges.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
68.35.Dv Composition, segregation; defects and impurities

Model for facet and sidewall defect formation during selective epitaxial growth of (001) silicon

C. I. Drowley, G. A. Reid, and R. Hull

Appl. Phys. Lett. 52, 546 (1988); http://dx.doi.org/10.1063/1.99412 (3 pages) | Cited 36 times

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An atomistic growth model is used to explain sidewall facet and defect formation during selective epitaxial growth of (001) silicon. Films grown through oxide windows with {110} sidewall orientations exhibit facets (typically {311} planes) adjacent to the sidewall. This region also has a high density of twins. Films grown in windows oriented to have {100} sidewalls have no sidewall facets and a very low defect density. The facet morphology and twin formation at {110} sidewalls are both explained by the influence of the oxide on nucleation of {111} planes. Similar considerations indicate that films grown along {100} sidewalls are less susceptible to facet and defect formation, as observed. Experimental data on film morphology and defect structure are used to support the model.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.-a Thin film structure and morphology

Organometallic vapor phase epitaxial growth of a new semiconductor alloy: GaP1−xSbx

M. J. Jou, Y. T. Cherng, H. R. Jen, and G. B. Stringfellow

Appl. Phys. Lett. 52, 549 (1988); http://dx.doi.org/10.1063/1.99413 (3 pages) | Cited 29 times

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The III/V semiconductor alloy GaP1−xSbx has been grown for the first time. This alloy, which has a large miscibility gap at the growth temperatures of 530–600 °C, has been grown by organometallic vapor phase epitaxy at atmospheric pressure. In spite of the miscibility gap, which is calculated to extend from x=0.01 to 0.99 at 530 °C, layers with excellent surface morphologies could be grown throughout the entire composition range. The 10 K energy band gap has been determined as a function of composition by using photoluminescence, x‐ray diffraction, and electron microprobe analysis, yielding bowing parameters of 3.8 and 2.7 eV for the Γ and X conduction band minima, respectively.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.55.Cr III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems

High‐speed performance of InP/In0.53Ga0.47As/InP double‐heterojunction bipolar transistors

T. Won and H. Morkoç

Appl. Phys. Lett. 52, 552 (1988); http://dx.doi.org/10.1063/1.99414 (3 pages) | Cited 4 times

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A theoretical comparison of In0.53Ga0.47As/InP and Al0.3Ga0.7As/GaAs heterojunction bipolar transistors has been undertaken in an effort to determine the relative merits of these material systems. The analysis uses a compact transistor model and considers devices with self‐aligned geometries including both extrinsic and intrinsic parameters. The high electron mobility in the In0.53Ga0.47As base layer and high peak velocity of electrons in the collector depletion layer result in a current gain cutoff frequency in excess of 150 GHz for an InP/In0.53Ga0.47As transistor with base thickness of 0.1 μm. Calculations revealed, however, that maximum oscillation frequency is strongly dependent on the contact resistance of the p‐type base layer, even for a self‐aligned base transistor. A maximum oscillation frequency of 138 GHz is theoretically predicted for an InP/In0.53Ga0.47As transistor with base thickness of 0.06 μm, base doping of 1×1020 cm−3, a p‐type contact resistance of 1.0×10−7 Ω cm2, a current density of 5×104 A/cm2, and a VCB of 5 V.
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85.30.Pq Bipolar transistors
85.30.De Semiconductor-device characterization, design, and modeling

Stress variations and relief in patterned GaAs grown on mismatched substrates

B. G. Yacobi, C. Jagannath, S. Zemon, and P. Sheldon

Appl. Phys. Lett. 52, 555 (1988); http://dx.doi.org/10.1063/1.99415 (3 pages) | Cited 41 times

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Cathodoluminescence scanning electron microscopy studies reveal significant variations in stress across etched patterns of GaAs grown on both InP and Si substrates. The stress in the epilayer is relieved at convex corners and in patterned areas with dimensions on the order of 10 μm. The stress is uniaxial near the edge of a patterned region and changes to biaxial away from the edge, producing nonuniformities in the optical properties of patterned regions.
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68.60.Bs Mechanical and acoustical properties
68.35.B- Structure of clean surfaces (and surface reconstruction)
78.60.Hk Cathodoluminescence, ionoluminescence
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

Entropy factor of donor level in gold implanted silicon

S. Coffa, G. Calleri, L. Calcagno, S. U. Campisano, and G. Ferla

Appl. Phys. Lett. 52, 558 (1988); http://dx.doi.org/10.1063/1.99416 (3 pages) | Cited 6 times

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Rutherford backscattering spectrometry and spreading resistance techniques have been used to determine the concentration profiles of gold implanted on and diffused in p‐type silicon. The measurement of the gold concentration is possible by the solution of the charge neutrality condition and thus it requires the determination of the entropy factor X associated with the ionization of the gold donor level. The value of 28±2 compares well with the latest determination of X obtained by using rather complex techniques.
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61.72.sd Impurity concentration
61.72.sh Impurity distribution
61.72.sm Impurity gradients
66.30.J- Diffusion of impurities

Interface degradation in Si‐metal‐oxide‐semiconductor structures by homogeneous, microwave heating of channel carriers

Ye Qiu‐Yi, A. Zrenner, F. Koch, C. Zeller, and G. Dorda

Appl. Phys. Lett. 52, 561 (1988); http://dx.doi.org/10.1063/1.99417 (3 pages)

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Using a pulsed microwave source to provide a strong lateral electric field in a Si‐metal‐oxide‐semiconductor structure, we observe interface degradation by hot holes. Damage occurs in a two‐step process. Holes are trapped in the oxide at low temperature and are subsequently converted into interface states in an annealing step at room temperature.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.25.+i Surface conductivity and carrier phenomena
73.20.Hb Impurity and defect levels; energy states of adsorbed species
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths

Mode structure of the p‐germanium far‐infrared laser with and without external mirrors: Single line operation

K. Unterrainer, M. Helm, E. Gornik, E. E. Haller, and J. Leotin

Appl. Phys. Lett. 52, 564 (1988); http://dx.doi.org/10.1063/1.99418 (3 pages) | Cited 16 times

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The mode structure of p‐Ge far‐infrared lasers with and without mirrors is investigated. Without external mirrors a multimode spectrum is observed and quantitatively explained in terms of waveguidelike modes. An external resonator drastically reduces the number of oscillating modes. For the first time single line operation is demonstrated in this configuration.
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42.55.Px Semiconductor lasers; laser diodes
78.45.+h Stimulated emission
42.60.Fc Modulation, tuning, and mode locking
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Chemical ordering in GaxIn1−xP semiconductor alloy grown by metalorganic vapor phase epitaxy

P. Bellon, J. P. Chevalier, G. P. Martin, E. Dupont‐Nivet, C. Thiebaut, and J. P. André

Appl. Phys. Lett. 52, 567 (1988); http://dx.doi.org/10.1063/1.99419 (3 pages) | Cited 73 times

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GaInP films grown by metalorganic vapor phase epitaxy on GaAs substrates are observed by transmission electron microscopy in cross sections. A 1/2 (111) (CuPt type) ordering is observed, for the first time in this system, with only two orientation variants occurring. A layered structure (layer thickness 2 nm) develops parallel to the substrate and extra diffuse scattering is also observed at 2/9 (220). The observation of the 1/2 (111) ordering is not predicted by the current first‐principle phase diagram calculations. Substrate effects on the orientation and number of ordering variants are identified.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.Nq Composition and phase identification
07.79.Cz Scanning tunneling microscopes
61.05.-a Techniques for structure determination

Use of Raman spectroscopy to examine the effects of growth stops on the interfaces of superlattices grown by molecular beam epitaxy

G. W. Wicks, J. T. Bradshaw, and D. C. Radulescu

Appl. Phys. Lett. 52, 570 (1988); http://dx.doi.org/10.1063/1.99396 (3 pages) | Cited 7 times

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Raman spectroscopy of confined longitudinal optical phonons is used to examine the abruptness of the interfaces in a sequence of (GaAs)7(AlAs)7 superlattice samples grown by molecular beam epitaxy. The duration and stoichiometry of growth stops at each heterointerface was varied throughout the sequence. Arsenic rich, group III rich, and approximately stoichiometric growth stops were investigated. It was found that, when the arsenic beam remains on during the growth stops, the surfaces continuously become smoother, resulting in more abrupt interfaces. However, when growth is stopped under group III rich or stoichiometric conditions, an initial roughening of the surface occurs, followed by gradual smoothing.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
68.35.B- Structure of clean surfaces (and surface reconstruction)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.30.Fs III-V and II-VI semiconductors

Radiation and hot‐electron effects on SiO2/Si interfaces with oxides grown in O2 containing small amounts of trichloroethane

Yu Wang, Yasushiro Nishioka, T. P. Ma, and R. C. Barker

Appl. Phys. Lett. 52, 573 (1988); http://dx.doi.org/10.1063/1.99397 (3 pages) | Cited 13 times

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The hardness of SiO2/Si structures grown in O2+TCA (1,1,1,‐trichloroethane) to damages caused by ionizing radiation and hot‐electron injection has been found to depend strongly on the amount of TCA introduced. Using minute amounts (much smaller than conventionally used) of TCA, we have been able to achieve a dramatic improvement of the hardness. When excess amounts of TCA are used, however, the hardness degrades. In addition, the use of TCA also causes a significant change in the gate size dependence of the radiation or hot‐electron‐induced interface traps. These results will be explained in terms of the effects of Cl on the interfacial strain near the SiO2/Si transition region.
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61.80.Cb X-ray effects
61.80.Fe Electron and positron radiation effects
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
81.40.Pq Friction, lubrication, and wear

Disk hydrogen plasma assisted chemical vapor deposition of aluminum nitride

T. Y. Sheng, Z. Q. Yu, and G. J. Collins

Appl. Phys. Lett. 52, 576 (1988); http://dx.doi.org/10.1063/1.99398 (3 pages) | Cited 29 times

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We employ a well‐confined hydrogen plasma of disk shape both as a vacuum ultraviolet (VUV) lamp operating primarily at 121.5 nm and as a source of atomic hydrogen radicals. Both VUV photons and atomic hydrogen act to dissociate feedstock gases used in low‐temperature (<400 °C) metalorganic chemical vapor deposition (MOCVD). Thin films have been deposited both with the confined hydrogen plasma and with an excimer laser operating at 193 nm in order to compare the two methods. Preliminary chemical and electrical properties of the films deposited via the two methods indicate the superiority of the atomic hydrogen assisted MOCVD technique.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.61.Ng Insulators
68.60.Wm Other nonelectronic physical properties

Characterization of GaAs film grown on Si substrate by photoluminescence at 77 K

Yihe Huang, Peter Y. Yu, Henry Lee, and Shyh Wang

Appl. Phys. Lett. 52, 579 (1988); http://dx.doi.org/10.1063/1.99371 (3 pages) | Cited 13 times

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Photoluminescence of GaAs films grown on Si substrate has been investigated quantitatively at 77 K. The peak shift and splitting of the exciton luminescence are shown to result from tensile stress in the film. Information on carrier lifetime has been deduced from the line shape of the photoluminescence.
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78.55.Cr III-V semiconductors
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
68.60.Bs Mechanical and acoustical properties

Anomalous reduction of lattice parameter by residual impurity boron in undoped Czochralski‐grown GaAs

Yasumasa Okada and Fumio Orito

Appl. Phys. Lett. 52, 582 (1988); http://dx.doi.org/10.1063/1.99372 (2 pages) | Cited 8 times

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An anomalous reduction of lattice parameter is observed for undoped semi‐insulating liquid encapsulated Czochralski‐grown GaAs by precision lattice parameter measurements with the use of the bond method. The anomalous reduction is though to be due to the incorporation of residual boron from the B2O3 encapsulant. The reduction rate is about 2 times larger than the predicted rate for the boron concentration derived from Vegard’s law. Possible defect models for this phenomenon are discussed.
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61.66.Fn Inorganic compounds
72.80.Ey III-V and II-VI semiconductors
61.72.jd Vacancies
61.72.jj Interstitials
61.72.sd Impurity concentration
61.72.sh Impurity distribution
61.72.sm Impurity gradients

Y‐Ba‐Cu‐O superconducting thin films by simultaneous or sequential evaporation

A. Mogro‐Campero, B. D. Hunt, L. G. Turner, M. C. Burrell, and W. E. Balz

Appl. Phys. Lett. 52, 584 (1988); http://dx.doi.org/10.1063/1.99373 (3 pages) | Cited 43 times

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Superconducting thin films of Y‐Ba‐Cu‐O near the 1:2:3 stoichiometry were produced by simultaneous (coevaporation) and sequential (multilayer) evaporation in the same evaporator. The best film obtained on yttria‐stabilized zirconia (YSZ) had a superconducting onset temperature of 104 K, a midpoint Tc of 92 K, and zero resistance at T≤74 K. Stoichiometry was deduced by inductively coupled plasma emission spectroscopy, and elemental depth profiles were obtained by x‐ray photoelectron spectroscopy. Film stoichiometry changes only near the film/substrate boundary for films on YSZ. Films on Si/SiO2 were not superconducting; depth profiling shows severe changes of film composition with depth. A major theme of this work is process reproducibility, which was found to be poor for coevaporation but improved considerably for sequential evaporation.
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74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
68.55.Nq Composition and phase identification

Y‐Ba‐Cu‐O thin films prepared by a multilayer vacuum method

C. X. Qiu and I. Shih

Appl. Phys. Lett. 52, 587 (1988); http://dx.doi.org/10.1063/1.99374 (3 pages) | Cited 11 times

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Polycrystalline Y‐Ba‐Cu‐O thin films with a thickness of about 1 μm have been deposited on alumina substrates. The deposition was made by first sequentially evaporating Y/Ba/Cu layers followed by a heat treatment in an environment containing oxygen. The treated films were polycrystalline, and the electrical results showed an onset temperature of about 100 K and a zero‐resistance temperature of 78 K for the films treated at 850 °C for 2 h in oxygen.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
81.40.Rs Electrical and magnetic properties related to treatment conditions
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