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18 Jul 1994

Volume 65, Issue 3, pp. 259-380

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Symmetry considerations in vertical‐cavity surface‐emitting lasers: Prediction of removal of polarization isotropicity on (001) substrates

Daryoosh Vakhshoori

Appl. Phys. Lett. 65, 259 (1994); http://dx.doi.org/10.1063/1.112410 (3 pages) | Cited 15 times

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The effects of crystalline and structural symmetry on the performance of vertical‐cavity surface‐emitting laser structures are studied by group theoretical techniques. It is shown that an asymmetrically designed active region (i.e., saw‐tooth quantum wells) will make the gain anisotropic with respect to the two different transverse polarization on (001) substrates with eigenvectors along [110] and [110] directions. Removal of gain degeneracies is also shown for tilted substrates with the corresponding tabulation of the eigendirections. The gain/loss anisotropicity is required to make polarization stablized lasers.
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78.66.Fd III-V semiconductors
42.55.Px Semiconductor lasers; laser diodes

Photorefractive polymer composite with net gain and subsecond response at 633 nm

G. G. Malliaras, V. V. Krasnikov, H. J. Bolink, and G. Hadziioannou

Appl. Phys. Lett. 65, 262 (1994); http://dx.doi.org/10.1063/1.112411 (3 pages) | Cited 16 times

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By combining the well‐known photoconductor poly(N‐vinyl carbazole) sensitized with 2,4,7 trinitro‐9‐fluorenone and the electrooptic molecule N,N, diethyl‐substituted para‐nitroaniline, which is transparent at 633 nm, a photorefractive polymer composite suitable for applications with He‐Ne lasers was developed. Net gain of 18 cm−1 and 400 ms response time were measured on a 65‐μm‐thick sample.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
78.20.Jq Electro-optical effects
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Nonlinear optical studies of a fluorinated poled polyimide guest‐host system

S. F. Hubbard, K. D. Singer, F. Li, S. Z. D. Cheng, and F. W. Harris

Appl. Phys. Lett. 65, 265 (1994); http://dx.doi.org/10.1063/1.112412 (3 pages) | Cited 5 times

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We report on poling of a low dielectric constant preimidized fluorinated fully aromatic guest‐host polyimide nonlinear optical material including thermal stability of optical nonlinearities and waveguiding properties. We measured a second‐harmonic coefficient (d33=4.9±0.5 pm/V at 1217 nm fundamental wavelength) which is accurately predicted by a thermodynamic model of poled polymers. The optical nonlinearity of a poled sample was thermally stable at 80 °C for over 300 h. Films were observed to have negative birefringence. Optical losses for slab waveguides in lowest order TE and TM modes were ≥7.7 dB/cm for doped waveguides at 800 nm wavelength and increased after poling.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.20.Fm Birefringence
78.66.Qn Polymers; organic compounds

High repetition rate traveling wave optical parametric generator producing nearly bandwidth limited 50 fs infrared light pulses

V. Petrov, F. Seifert, and F. Noack

Appl. Phys. Lett. 65, 268 (1994); http://dx.doi.org/10.1063/1.112367 (3 pages) | Cited 22 times

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A 1 kHz Ti:sapphire femtosecond regenerative amplifier system is used to pump a lithium triborate optical parametric generator in a type II noncritical phase matching configuration and a β‐barium borate parametric amplifier. Infrared pulses near 1460 nm as short as 50 fs are achieved with a pulse duration/bandwidth product of only 0.44.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.79.Nv Optical frequency converters

Crosstalk in dynamic optical interconnects in photorefractive crystals

Peter E. Andersen, Paul M. Petersen, and Preben Buchhave

Appl. Phys. Lett. 65, 271 (1994); http://dx.doi.org/10.1063/1.112368 (3 pages) | Cited 7 times

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We have investigated the crosstalk between two neighboring gratings in photorefractive Bi12SiO20 optical interconnects. The gratings are induced by the interference between one reference beam and two object beams. By applying a suitable phase shift in one of the object beams, we can selectively switch off one of the gratings. The crosstalk between the two gratings is experimentally determined from the diffraction efficiency in the remaining grating before and after applying the phase shift. The magnitude of the crosstalk is determined by the intensity ratio between the reference beam intensity and the object beam intensity. Crosstalk can be avoided by choosing a certain intensity ratio between the reference and the object beams.
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42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.40.-i Holography

Absolute active frequency locking of a diode laser with optical feedback generated by Doppler‐free collinear polarization spectroscopy

Zi Dong Liu, Daniel Bloch, and Martial Ducloy

Appl. Phys. Lett. 65, 274 (1994); http://dx.doi.org/10.1063/1.112369 (3 pages) | Cited 4 times

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Absolute stabilization of the emission frequency of a laser diode can be achieved in a nearly all‐optical scheme involving a resonant optical feedback from an atomic signal. We propose here two novel schemes of collinear Doppler‐free polarization spectroscopy and report on preliminary experimental demonstrations of diode frequency locking performed on the D2 line of Rb.
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42.60.Fc Modulation, tuning, and mode locking
42.62.Fi Laser spectroscopy
42.55.Px Semiconductor lasers; laser diodes
42.65.-k Nonlinear optics

Modulation‐doped GaInAs/GaInAsP strained multiple‐quantum‐well lasers grown by chemical beam epitaxy

Hiroyasu Mawatari, Ryuzu Iga, Hideo Sugiura, Yuichi Tohmori, and Yuzo Yoshikuni

Appl. Phys. Lett. 65, 277 (1994); http://dx.doi.org/10.1063/1.112371 (3 pages) | Cited 2 times

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We report the characteristics of Be‐modulation‐doped strained multiple‐quantum‐well (MQW) buried heterostructure lasers grown by chemical‐beam epitaxy. Secondary ion mass spectroscopy revealed that the Be‐modulation‐doping profile was fabricated and maintained even after annealing at 620 °C for 30 min, which is the same condition used to fabricate the buried heterostructure. A linewidth enhancement factor (α parameter) of only 0.8 was obtained in 3×1018 cm−3 Be‐modulation‐doped strained MQW Fabry–Perot lasers at a wavelength of 35 nm shorter than the gain peak.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Distinction of two‐photon absorption from other nonlinear loss mechanisms by phase‐conjugate interferometry

Peter Tackx, Martti Kauranen, and André Persoons

Appl. Phys. Lett. 65, 280 (1994); http://dx.doi.org/10.1063/1.112375 (3 pages)

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We show that phase‐conjugate interferometry is a measuring technique for third‐order optical nonlinearities that can distinguish two‐photon absorption from other nonlinear loss mechanisms. For the case of 3,3′‐diethyloxadicarbocyanine iodide at 1064 nm, the nonlinear loss is dominated by linear absorption from the two‐photon excited state. We observe a highly nonlinear absorption process in solutions of 4‐methoxy‐4′‐nitrostilbene at 532 nm and show that it is due to a more complicated loss mechanism. This mechanism could have applications in optical limiting.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.66.Qn Polymers; organic compounds

Experimental investigation on high‐speed switching characteristics of a novel symmetric Mach–Zehnder all‐optical switch

S. Nakamura, K. Tajima, and Y. Sugimoto

Appl. Phys. Lett. 65, 283 (1994); http://dx.doi.org/10.1063/1.112347 (3 pages) | Cited 42 times

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We report the experimental results of a novel symmetric Mach–Zehnder (SMZ) all‐optical switch. Although the switching is based on the band‐filling effect in the semiconductor waveguide, the switching speed is not restricted by the slow relaxation time. We obtain fully switched, nearly square modulation, which is characteristic of the SMZ all‐optical switch. We also achieve high‐speed switching; the full width at half‐maximum of the obtained wave form is 8 ps, which is only limited by the time resolution of the detection system.
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42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

High peak power, burst mode operation of a multikilowatt CO2 laser for deep penetration welding

S. W. C. Scott, K. Rogozinski, and H. J. J. Seguin

Appl. Phys. Lett. 65, 286 (1994); http://dx.doi.org/10.1063/1.112348 (3 pages) | Cited 1 time

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A significant advancement in laser welding of heavy metal sections is presented. Operation of a photoinitiated, impulse‐enhanced, electrically excited multikilowatt continuous wave (cw) laser in the pulse periodic regime results in significant improvement in weld penetration depth. High average power pulsed operation is made possible through the use of a low level trigger for a digitally controlled hydrogen thyratron pulser circuit. Peak optical powers on the order of 3 times the cw level are produced while maintaining multikilowatt average output power. A comparison of cw and pulsed welding of X70 pipeline steel is included. Burst mode welding with this system is found to yield up to a 50% increase in weld penetration with a superior weld profile when compared to cw welding at the same average power level.
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42.62.Cf Industrial applications
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.By Design of specific laser systems

Third‐order optical nonlinearity of conjugated poly(4,4‐disubstituted‐1,6‐heptadiyne)s

Soo Young Park, Hyun‐Nam Cho, Nakjoong Kim, Jong‐Wook Park, Sung‐Ho Jin, Sam‐Kwon Choi, Tatsuo Wada, and Hiroyuki Sasabe

Appl. Phys. Lett. 65, 289 (1994); http://dx.doi.org/10.1063/1.112349 (3 pages) | Cited 2 times

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Large third‐order optical nonlinearity was found with the soluble conjugated polymers (substituted polyacetylenes) synthesized by the ring‐forming metathesis polymerization of 4,4‐disubstituted‐1,6‐heptadiynes. These polymers were of quite high molecular weight (∼105) and were highly soluble in common organic solvents. The linear optical property and the third‐order optical nonlinearity of these polymers were investigated in terms of the chemical structure of the 4,4‐disubstituents using the polymer films of around 100‐nm thickness fabricated by the spin coating of tetrahydrofuran solutions. The π‐π∗ transition of the conjugated π‐electron main chain was characterized as the strong absorption peak at around 540 nm of the electronic spectra, where the optical density of the transition was found to be largely dependent on the molar volume of the substituents. The near‐resonant values of the third‐order nonlinear optical coefficient, χ(3)(−3ω;ω,ω,ω) were found to be 2.6 to 6.5×10−11 esu, which also were controlled by the molar volume of the substituent group.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Qn Polymers; organic compounds
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials
82.35.-x Polymers: properties; reactions; polymerization

Imaging of boron dopant in highly oriented diamond films by cathodoluminescence in a transmission electron microscope

R. J. Graham, F. Shaapur, Y. Kato, and B. R. Stoner

Appl. Phys. Lett. 65, 292 (1994); http://dx.doi.org/10.1063/1.112350 (3 pages) | Cited 11 times

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Boron‐doped, highly oriented, (100) textured diamond films have been examined by cathodoluminescence in a transmission electron microscope to assess the distribution of the defects and boron dopant within the films. Dislocation‐related luminescence, which is believed to be unrelated to boron, was found to originate inhomogeneously in the films, from dislocations within single grains and at grain boundaries. Luminescence from donor‐acceptor pairs involving boron was imaged with submicron spatial resolution to show that boron dopant is uniformly distributed from grain to grain and within individual grains, in these diamond films. The dislocation density in undoped films grown under similar conditions was found to be much lower than in B‐doped films, suggesting that the introduction of B not only results in its incorporation as a dopant, but also gives rise to dislocations.
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78.60.Hk Cathodoluminescence, ionoluminescence
78.66.Db Elemental semiconductors and insulators
68.37.Hk Scanning electron microscopy (SEM) (including EBIC)
68.37.Lp Transmission electron microscopy (TEM)

Crystallization of sol‐gel deposited potassium‐tantalate‐niobate thin films on platinum

Azar Nazeri

Appl. Phys. Lett. 65, 295 (1994); http://dx.doi.org/10.1063/1.112351 (3 pages) | Cited 5 times

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Potassium tantalate niobate (KTN) ferroelectric thin films prepared by sol‐gel processing have been heat treated in conventional furnaces and through rapid thermal annealing (RTA) to investigate crystallization of the films. Various key factors such as time and temperature influencing the crystallization have been identified. A post‐deposition RTA at 750 °C in nitrogen for 5 min crystallized the KTN films into pure perovskite while it took two hours to completely crystallize a similar KTN film in conventional ovens. The effect of preheat treatment at lower temperatures, solution chemistry, and the thickness have also been studied. Preliminary ferroelectric properties of some samples are also presented.
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77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
81.05.Rm Porous materials; granular materials

In situ laser‐induced fluorescence studies of laser chemical vapor deposition of TiN thin films

Xiangli Chen and Jyoti Mazumder

Appl. Phys. Lett. 65, 298 (1994); http://dx.doi.org/10.1063/1.112352 (3 pages) | Cited 6 times

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TiN films are deposited on Si(100) from a reactant gas mixture of TiCl4, N2, and H2 by chemical vapor deposition with a CO2 laser. Pulsed dye laser‐induced fluorescence spectroscopy is applied to obtain gas phase species concentration during deposition in order to study the reaction and film growth mechanisms. Ti atomic species are found close to the substrate surface with concentrations in the order of 1011 cm−3.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
78.55.Hx Other solid inorganic materials

Surface analysis of a GaAs electron source using Rutherford backscattering spectroscopy

R. Calabrese, V. Guidi, P. Lenisa, B. Maciga, G. Ciullo, G. Della Mea, G. P. Egeni, G. Lamanna, V. Rigato, V. Rudello, B. Yang, S. Zandolin, and L. Tecchio

Appl. Phys. Lett. 65, 301 (1994); http://dx.doi.org/10.1063/1.112353 (2 pages) | Cited 5 times

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We experimented with Rutherford backscattering spectroscopy to measure the amount of cesium on the surface of a GaAs photocathode activated in negative electron affinity (NEA) conditions. The surface analysis was performed both immediately after activation of the source in NEA condition and also some time after its total spoiling. Results showed that cesium did not desorb from the GaAs surface. With any further cesium feeding to reactivate the surface, the cesium accumulated on the surface until a saturation level was reached.
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29.25.Bx Electron sources
61.85.+p Channeling phenomena (blocking, energy loss, etc.)

Mechanical alloying process of the zirconia–8 mol % yttria ceramic powder

Y. L. Chen, M. Qi, J. S. Wu, D. H. Wang, and D. Z. Yang

Appl. Phys. Lett. 65, 303 (1994); http://dx.doi.org/10.1063/1.113022 (3 pages) | Cited 7 times

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The phase transformation process of zirconia–8 mol % yttria powder mixtures during a high energy ball milling process has been studied by means of x‐ray diffraction analysis. It has been found that the m‐ZrO2 (monoclinic zirconia) transforms first to m‐ZrO2 solid solution and then to t‐ZrO2 (tetragonal zirconia) solid solution. Finally, a single cubic zirconia solid solution phase forms after prolonged milling. The structural transformation is discussed and explained in terms of the phase relations in zirconia‐yttria ceramics and the nonequilibrium nature of the mechanical alloying.
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61.66.Dk Alloys

Defect accumulation during ion irradiation of crystalline Si probed by in situ conductivity measurements

A. Battaglia, S. Coffa, F. Priolo, and C. Spinella

Appl. Phys. Lett. 65, 306 (1994); http://dx.doi.org/10.1063/1.112354 (3 pages) | Cited 4 times

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We have used in situ conductivity measurements to investigate the defect evolution and accumulation in ion implanted crystalline Si. Upon irradiation at room temperature with 400 keV Si ions the initial conductivity (4×10−2 Ω−1 cm−1) decreases by about 4 orders of magnitude to a value of 2×10−6 Ω−1 cm−1, characteristic of intrinsic silicon, at a fluence of 1×1013/cm2 and then slowly increases at higher fluences. Deep level transient spectroscopy measurements, transmission electron microscopy analyses, and thermal annealings were performed on samples irradiated at various fluences. The data demonstrate that the strong conductivity decrease at low fluences is the result of a dopant compensation produced by deep levels introduced by divacancies and complex defects in the band gap. At higher fluences the conduction is dominated by electron hopping in a buried continuous amorphous layer produced by irradiation. These results are reported and discussed.
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61.72.Cc Kinetics of defect formation and annealing
61.80.Jh Ion radiation effects
72.80.Cw Elemental semiconductors

Thermal conductivity of sputtered and evaporated SiO2 and TiO2 optical coatings

David G. Cahill and Thomas H. Allen

Appl. Phys. Lett. 65, 309 (1994); http://dx.doi.org/10.1063/1.112355 (3 pages) | Cited 35 times

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The thermal conductivity of SiO2 and TiO2 optical coatings are measured in the temperature range 80–400 K. For SiO2, the thermal conductivity of sputtered and evaporated films are 77% and 55% of the bulk value, respectively, independent of temperature. Similarly, the thermal conductivity of evaporated TiO2 is 63% of the conductivity of sputtered TiO2.
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72.15.Cz Electrical and thermal conduction in amorphous and liquid metals and alloys
73.50.Lw Thermoelectric effects

Noncontact determination of transverse isotropic elastic moduli in polyimide thin films using a laser based ultrasonic method

John A. Rogers, Lisa Dhar, and Keith A. Nelson

Appl. Phys. Lett. 65, 312 (1994); http://dx.doi.org/10.1063/1.112356 (3 pages) | Cited 29 times

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A transient grating laser ultrasonic method known as real‐time impulsive stimulated thermal scattering is used to excite and monitor Lamb acoustic waveguide modes in free‐standing thin polyimide films which are known to have transverse isotropic symmetry. The dispersion of these Lamb modes is used to accurately evaluate both the in and out‐of‐plane elastic moduli.
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78.20.hb Piezo-optical, elasto-optical, acousto-optical, and photoelastic effects
43.35.Sx Acoustooptical effects, optoacoustics, acoustical visualization, acoustical microscopy, and acoustical holography
78.66.Qn Polymers; organic compounds

1/f noise and electromigration in aluminum films: The role of film microstructure and texture

R. G. Smith, G. A. Biery, and K. P. Rodbell

Appl. Phys. Lett. 65, 315 (1994); http://dx.doi.org/10.1063/1.112357 (3 pages) | Cited 6 times

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The role of crystallographic texture on excess noise and the ability of excess noise to predict the electromigration behavior of pure aluminum films is examined. We report the excess noise and electromigration behavior of pure Al films which were deposited under a variety of conditions to obtain significantly different crystallographic textures. The noise magnitude and the logarithmic slope (α) were measured on three distinct sets of aluminum films as a function of linewidth (∼0.5–2 μm). Previously the electromigration lifetimes of these films were directly related to the (111) volume fraction. This study shows that excess noise is inversely proportional to the (111) volume fraction, suggesting that excess noise may not be measuring the same rate limiting atomic process as electromigration. The effect of film texture combined with a lower noise magnitude with decreasing linewidth implies that grain boundaries are a major source of noise in Al films.
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73.50.Td Noise processes and phenomena
81.30.-t Phase diagrams and microstructures developed by solidification and solid-solid phase transformations
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Inverse melting of a metastable Nb45Cr55 solid solution

C. Michaelsen, M. Oehring, and R. Bormann

Appl. Phys. Lett. 65, 318 (1994); http://dx.doi.org/10.1063/1.112358 (3 pages) | Cited 10 times

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An Nb45Cr55 solid solution was prepared by mechanical alloying in a planetary ball mill and investigated by x‐ray diffraction and calorimetry. It was found that the structure evolution upon heating exhibited three distinct stages, the first resulting in complete amorphization, whereas the second and third are related to the subsequent crystallization of the amorphous phase. These results are in agreement with the free‐energy functions calculated from the thermochemical data of the system. They show that for a composition of Nb45Cr55 a second melting point (often termed ‘‘inverse melting point’’) exists at about 900 °C, below which the undercooled liquid has a lower free energy than the crystalline body‐centered‐cubic phase.
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64.60.My Metastable phases
81.30.-t Phase diagrams and microstructures developed by solidification and solid-solid phase transformations
64.70.D- Solid-liquid transitions

Microstructure of AlN on Si (111) grown by plasma‐assisted molecular beam epitaxy

K. S. Stevens, A. Ohtani, M. Kinniburgh, and R. Beresford

Appl. Phys. Lett. 65, 321 (1994); http://dx.doi.org/10.1063/1.112359 (3 pages) | Cited 44 times

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We have grown monocrystalline AlN on Si (111) substrates over the temperature range 550–900 °C using electron cyclotron resonance plasma assisted molecular beam epitaxy. The best (0002) peak omega rocking curve full width at half‐maximum value obtained was 26 min for a film deposited at 900 °C. All films nominally displayed the AlN[0001]∥Si[111] orientation. The exact angle between AlN[0001] and Si[111] decreased from 2.1° to 1.1° and the (0002) peak widths improved with increasing substrate temperature. Mosaic‐type disorder was shown by high resolution x‐ray diffraction to be the dominant cause of the ω rocking curve peak full widths.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.-a Thin film structure and morphology
68.35.B- Structure of clean surfaces (and surface reconstruction)
61.05.cf X-ray scattering (including small-angle scattering)
61.05.cj X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.

Diffusion of ion implanted Sn in Si, Si1−xGex, and Ge

Per Kringhøj and Robert G. Elliman

Appl. Phys. Lett. 65, 324 (1994); http://dx.doi.org/10.1063/1.112360 (3 pages) | Cited 13 times

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The chemical distribution of Sn ion implanted into Si, Si0.79Ge0.21, Si0.47Ge0.53, and Ge was measured with secondary ion mass spectrometry. By comparing the chemical distribution of Sn before and after high temperature annealing, the diffusion coefficient of Sn was extracted as a function of temperature. The diffusion coefficients exhibited Arrhenius behavior in all four cases, yielding activation energies for diffusion of 4.91, 4.61, 3.88, and 3.05 eV, respectively, for each of the four samples. At a given temperature the diffusion coefficient for Sn was found to increase almost exponentially with increasing Ge content. Although the diffusion coefficient for Sn in Si and Ge is higher, relative to the corresponding value for self‐diffusion, the activation energies are similar to that for Si and Ge self‐diffusion. This suggests that the diffusion mechanism for Sn is similar to that for self‐diffusion in Si and Ge and for SiGe alloys.
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66.30.J- Diffusion of impurities
61.72.uf Ge and Si
81.65.-b Surface treatments

Misfit dislocation propagation kinetics in GexSi1−x/Ge(100) heterostructures

R. Hull, J. C. Bean, L. J. Peticolas, B. E. Weir, K. Prabhakaran, and T. Ogino

Appl. Phys. Lett. 65, 327 (1994); http://dx.doi.org/10.1063/1.113023 (3 pages) | Cited 17 times

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We report measurements of misfit dislocation propagation velocities in GexSi1−x epilayers grown upon Ge(100) substrates, as opposed to the more usual Si(100) substrates. This geometry allows us to study structures with high Ge concentration (x≥0.8), and to compare with previous extensive measurements for lower Ge concentration layers (x≤0.35) grown upon Si(100). It is found that all data are well described by a misfit dislocation velocity which is linear with excess stress, and which incorporates a compositionally dependent activation energy with linear interpolation between bulk values for Si and Ge. The combined data sets from structures grown on Si(100) and Ge(100) substrates is analyzed in the framework of the diffusive double kink model for dislocation motion.
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61.72.Bb Theories and models of crystal defects
61.72.Cc Kinetics of defect formation and annealing
61.72.Lk Linear defects: dislocations, disclinations
68.55.-a Thin film structure and morphology

Kinetics of hydrogen interaction with SiO2‐Si interface trap centers

R. Khatri, P. Asoka‐Kumar, B. Nielsen, L. O. Roellig, and K. G. Lynn

Appl. Phys. Lett. 65, 330 (1994); http://dx.doi.org/10.1063/1.112361 (3 pages) | Cited 16 times

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The effects of low temperature (≤700 °C ) annealing on the thermal dissociation of hydrogen‐passivated interface trap centers of a SiO2‐Si(100) system is studied using positron annihilation spectroscopy. The Si—H bonds dissociate with an activation energy of 2.60±0.06 eV. Assuming that the anneal generates trap centers with a single charge, positron measurements indicate that ∼4.5×108 trap centers/cm2 are created by a 600 °C anneal.
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78.70.Bj Positron annihilation
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
61.72.Cc Kinetics of defect formation and annealing
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