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11 Dec 2006

Volume 89, Issue 24, Articles (24xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 89, 242109 (2006); http://dx.doi.org/10.1063/1.2405843 (3 pages)

Carlo R. da Cunha, Nobuyuki Aoki, Takahiro Morimoto, Yuichi Ochiai, Richard Akis, and David K. Ferry
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Experimental evidence of B clustering in amorphous Si during ultrashallow junction formation

D. De Salvador, G. Bisognin, M. Di Marino, E. Napolitani, A. Carnera, H. Graoui, M. A. Foad, F. Boscherini, and S. Mirabella

Appl. Phys. Lett. 89, 241901 (2006); http://dx.doi.org/10.1063/1.2402905 (3 pages) | Cited 9 times

Online Publication Date: 11 December 2006

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The authors have investigated ultrashallow p+/n-junction formation by solid-phase epitaxy, by using x-ray absorption near-edge spectroscopy measurements on the B K edge. A clear fingerprint of B–B clusters is detected in the spectra. The authors demonstrate that B clustering occurs during the very early stages of annealing-induced Si recrystallization, i.e., when B is still in an amorphous matrix. After complete regrowth the local structure around B remains the same as in the amorphous phase, implying that B clusters are transferred to the crystalline structure.
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61.43.Dq Amorphous semiconductors, metals, and alloys
64.70.K- Solid-solid transitions
68.55.A- Nucleation and growth
68.55.-a Thin film structure and morphology
78.70.Dm X-ray absorption spectra

Composite growth in highly undercooled Ni70.2Si29.8 eutectic alloy

Yiping Lu, Feng Liu, Gencang Yang, and Yaohe Zhou

Appl. Phys. Lett. 89, 241902 (2006); http://dx.doi.org/10.1063/1.2405875 (3 pages) | Cited 4 times

Online Publication Date: 11 December 2006

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High undercooling was achieved in eutectic Ni70.2Si29.8 alloy melt using glass fluxing combined with cyclic superheating. An unusual interlaced morphology is observed in the as-solidified microstructure. This composite structure is found for the first time. Its forming process can be ascribed to a composite growth concurring with recalescence.
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81.10.Fq Growth from melts; zone melting and refining
61.72.-y Defects and impurities in crystals; microstructure
64.70.D- Solid-liquid transitions
81.30.Fb Solidification

Surface pole figures by reflection high-energy electron diffraction

F. Tang, G.-C. Wang, and T.-M. Lu

Appl. Phys. Lett. 89, 241903 (2006); http://dx.doi.org/10.1063/1.2403916 (3 pages) | Cited 8 times

Online Publication Date: 11 December 2006

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The authors demonstrated that it is possible to construct a reflection high-energy electron diffraction (RHEED) pole figure of a polycrystalline film by recording multiple RHEED patterns as they rotate the substrate around the surface normal. Since electrons have limited penetration depth, the pole figure constructed is a surface pole figure. It is in contrast with the conventional x-ray pole figure which gives an average texture information of the entire film. Surface texture change, particularly the evolution of multiple preferred orientations, in polycrystalline Ru films grown by oblique angle vapor deposition has been observed using this RHEED surface pole figure technique.
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81.05.Bx Metals, semimetals, and alloys
68.55.-a Thin film structure and morphology
68.55.A- Nucleation and growth
61.05.jh Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED)
68.47.De Metallic surfaces
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Hugoniot-compression curve of Zr-based bulk metallic glass

T. Mashimo, H. Togo, Y. Zhang, Y. Uemura, T. Kinoshita, M. Kodama, and Y. Kawamura

Appl. Phys. Lett. 89, 241904 (2006); http://dx.doi.org/10.1063/1.2403931 (3 pages) | Cited 10 times

Online Publication Date: 11 December 2006

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The Hugoniot-compression curves of the Zr-based bulk metallic glass (Zr55Al10Ni5Cu30 in at. %) and the metallic compound crystal with the same composition were measured by means of the inclined-mirror photographic technique. A kink was observed on the Hugoniot curve at 14 GPa for the glass probably due to phase transition, while no kink was observed for the crystal. The Hugoniot elastic limit stress (6.2 GPa) of the glass was comparable to one of the crystal.
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81.05.Kf Glasses (including metallic glasses)
64.30.-t Equations of state of specific substances
61.43.Fs Glasses
81.40.Lm Deformation, plasticity, and creep
64.70.K- Solid-solid transitions
62.50.-p High-pressure effects in solids and liquids

Epitaxial growth of single-crystalline AlN films on tungsten substrates

Guoqiang Li, Tae-Won Kim, Shigeru Inoue, Koichiro Okamoto, and Hiroshi Fujioka

Appl. Phys. Lett. 89, 241905 (2006); http://dx.doi.org/10.1063/1.2404588 (3 pages) | Cited 6 times

Online Publication Date: 11 December 2006

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The authors have grown single-crystalline AlN(0001) films on W(110) substrates with an in-plane alignment AlN[11–20]‖W[001] at temperatures ranging from 450 to 600 °C by pulsed laser deposition. These AlN films have a clear sixfold symmetry without 30° rotational domains. When AlN films are grown at 450 °C, the interfacial reaction between AlN and W(110) is fully suppressed and a flat surface with a root-mean-square value as low as 0.20 nm for AlN films is obtained. These single-crystalline AlN films grown on W(110) open a good opportunity for the high performance film bulk acoustic wave resonators of the next generation.
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81.05.Ea III-V semiconductors
68.55.A- Nucleation and growth
68.55.-a Thin film structure and morphology
81.15.Fg Pulsed laser ablation deposition
68.35.B- Structure of clean surfaces (and surface reconstruction)
79.20.Kz Other electron-impact emission phenomena

Optical imaging of thin films with molecular depth resolution

R. Köhler, P. Lazar, and H. Riegler

Appl. Phys. Lett. 89, 241906 (2006); http://dx.doi.org/10.1063/1.2404601 (3 pages) | Cited 4 times

Online Publication Date: 11 December 2006

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Oxide layers of suitable thicknesses greatly enhance the reflectivity contrast from molecularly thin films deposited on silicon wafers. This interference enhancement can be used to visualize and to quantify film topologies with a thickness resolution well below 1 nm.
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68.55.-a Thin film structure and morphology
68.37.-d Microscopy of surfaces, interfaces, and thin films
78.66.Qn Polymers; organic compounds

Highly efficient GaN-based light emitting diodes with micropits

M. Hao, T. Egawa, and H. Ishikawa

Appl. Phys. Lett. 89, 241907 (2006); http://dx.doi.org/10.1063/1.2402219 (3 pages) | Cited 7 times

Online Publication Date: 12 December 2006

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Light emitting diodes (LEDs) on GaN templates with high-density V-shaped micropits have been grown and characterized by transmission electron microscopy, scanning electron microscopy, and photoluminescence. Higher emission efficiency has been obtained for the fabricated LEDs compared with those without V-shaped pits. The high efficiency of the LEDs is mainly attributed to the increase in light extraction efficiency due to the light extraction from the sidewalls of the V-shaped pits. The improved internal quantum efficiency of the device resulting from the reduction of the dislocation density in the light emitting area also contributes to the high efficiency of the LEDs.
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85.60.Jb Light-emitting devices

Three-dimensional size determination of particles with photoelectron emission microscopy

Liviu I. Chelaru and Frank-J. Meyer zu Heringdorf

Appl. Phys. Lett. 89, 241908 (2006); http://dx.doi.org/10.1063/1.2404968 (3 pages) | Cited 3 times

Online Publication Date: 12 December 2006

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We show that the aspect ratio and the size of particles at surfaces can be estimated with photoelectron emission microscopy when both linear and nonlinear processes are utilized. As the width of the particles is known from regular photoemission microscopy, a complete determination of the particles’ dimensions becomes possible by two-photon photoemission microscopy. Here, the light diffraction pattern of the illuminating light around the particles is emphasized by the nonlinear dependence of the photoemission yield on the electric field components at the surface. This allows the quantitative measurement of the aspect ratio of the particles. The results are in agreement with theory and atomic force microscopy measurements.
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07.78.+s Electron, positron, and ion microscopes; electron diffractometers
06.30.Bp Spatial dimensions (e.g., position, lengths, volume, angles, and displacements)
79.60.-i Photoemission and photoelectron spectra

Ablation of solids using a femtosecond extreme ultraviolet free electron laser

N. Stojanovic, D. von der Linde, K. Sokolowski-Tinten, U. Zastrau, F. Perner, E. Förster, R. Sobierajski, R. Nietubyc, M. Jurek, D. Klinger, J. Pelka, J. Krzywinski, L Juha, J. Cihelka, A. Velyhan, et al.

Appl. Phys. Lett. 89, 241909 (2006); http://dx.doi.org/10.1063/1.2405398 (3 pages) | Cited 12 times

Online Publication Date: 12 December 2006

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The ablation of solids by high energy femtosecond pulses from an extreme ultraviolet (XUV) free electron laser has been investigated using picosecond optical imaging. The time-resolved measurements are supplemented by an analysis of the permanent structural surface modifications. Compared with femtosecond optical excitation, distinct differences in the material response are found which are attributed to the increased penetration depth of the XUV radiation and the absence of any absorption nonlinearities.
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61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
52.38.Mf Laser ablation
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
41.60.Cr Free-electron lasers

High resolution measurements of strain and tilt distributions in SiGe mesas using electron backscatter diffraction

Angus J. Wilkinson

Appl. Phys. Lett. 89, 241910 (2006); http://dx.doi.org/10.1063/1.2403904 (3 pages) | Cited 6 times

Online Publication Date: 12 December 2006

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Electron backscatter diffraction allows the elastic strain and rotation tensors to be determined at high spatial resolution and with a strain sensitivity of ∼ 10−4. The technique is used to investigate variations of strains and rotations near the surface of 200 nm thick epitaxial layers of Si0.85Ge0.15 grown on a Si substrate patterned with mesa stripes. In wide mesa stripes the strain relaxation and lattice curvature are confined to the outer edges of the mesa. While in narrower mesas the relaxation extends across the entire mesa width. Measured stress levels confirm earlier predictions of the extent of relaxation with mesa width.
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68.60.Bs Mechanical and acoustical properties
68.55.-a Thin film structure and morphology
81.40.Jj Elasticity and anelasticity, stress-strain relations
62.40.+i Anelasticity, internal friction, stress relaxation, and mechanical resonances
62.20.D- Elasticity

Defect and stress characterization of AlN films by Raman spectroscopy

Vanni Lughi and David R. Clarke

Appl. Phys. Lett. 89, 241911 (2006); http://dx.doi.org/10.1063/1.2404938 (3 pages) | Cited 13 times

Online Publication Date: 13 December 2006

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Raman spectroscopy was used to characterize the residual stress and defect density of AlN thin films reactively sputtered on silicon (100). The authors studied the correlation between the shift of the E2 (high) phonon of AlN at 658 cm−1 and the film biaxial stress and obtained a biaxial piezospectroscopic coefficient of 3.7 GPa/cm−1. A correlation was found between the width of the Raman line, the oxygen concentration measured by secondary ion mass spectroscopy, and acoustic losses. This work lays the basis for the nondestructive assessment of two key thin film properties in microelectromechanical systems applications, namely, acoustic attenuation and residual stress.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
68.60.Bs Mechanical and acoustical properties
78.66.Fd III-V semiconductors
77.65.Bn Piezoelectric and electrostrictive constants
78.30.Fs III-V and II-VI semiconductors
63.20.D- Phonon states and bands, normal modes, and phonon dispersion

Growth and thermal stability of GaPO4 epitaxial thin films

J. D. Pedarnig, S. Roither, and M. Peruzzi

Appl. Phys. Lett. 89, 241912 (2006); http://dx.doi.org/10.1063/1.2404970 (3 pages) | Cited 2 times

Online Publication Date: 13 December 2006

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Thin epitaxial films of gallium orthophosphate (GaPO4) are grown on α-quartz (SiO2) substrates. Here, amorphous stoichiometric precursor layers fabricated by pulsed-laser deposition on (001) SiO2 substrates are transformed to crystalline GaPO4 by postannealing in air at 650–950 °C. Epitaxial films with thicknesses up to 300 nm exhibit strong in-plane and out-of-plane textures (angular widths <0.6°). Long-term annealing in air at temperatures above the α- to β-phase transition of the quartz substrate (573 °C) does not degrade the films.
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81.15.Fg Pulsed laser ablation deposition
68.55.A- Nucleation and growth
81.40.Gh Other heat and thermomechanical treatments
64.70.K- Solid-solid transitions

Quantifying stacking faults and vacancies in thin convectively assembled colloidal crystals

H. Wei, L. Meng, Y. Jun, and D. J. Norris

Appl. Phys. Lett. 89, 241913 (2006); http://dx.doi.org/10.1063/1.2404973 (3 pages) | Cited 7 times

Online Publication Date: 13 December 2006

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The authors determine the concentration and distribution of stacking faults and vacancies in colloidal crystals between 3 and 11 layers thick grown via convective assembly. The average stacking parameter 〈α〉 rises from 0.1 for samples 3 layers thick to 0.8 for ≥ 6 layers. For samples ≥ 6 layers, the authors also find that the stacking faults are less likely to be near the substrate. The average vacancy concentration is 2.1×10−3 per unit cell. Surprisingly, the layer-averaged vacancy concentration is lowest in the layer nearest the substrate and highest in the next nearest layer.
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82.70.Dd Colloids
61.72.Nn Stacking faults and other planar or extended defects
61.72.J- Point defects and defect clusters

Athermal crystallization induced by electronic excitations in ion-irradiated silicon carbide

A. Benyagoub, A. Audren, L. Thomé, and F. Garrido

Appl. Phys. Lett. 89, 241914 (2006); http://dx.doi.org/10.1063/1.2405410 (3 pages) | Cited 18 times

Online Publication Date: 13 December 2006

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Silicon carbide single crystals were irradiated at room temperature with low energy I ions and high energy Pb ions. It is found that the damaged layer formed by the elastic collisions generated during low energy I ion irradiation can readily be removed by the electronic excitations induced by swift Pb ions. This effect occurs at a temperature quite below that at which the conventional ion-beam induced crystallization process is generally achieved by nuclear energy loss. This finding is interesting both from a fundamental point of view for the understanding of the interaction of swift heavy ions with solids and for a large number of technological applications.
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61.80.Jh Ion radiation effects
61.82.Fk Semiconductors
64.70.D- Solid-liquid transitions

Thermodynamic model for growth mechanisms of multiwall carbon nanotubes

F. H. Kaatz, M. P. Siegal, D. L. Overmyer, P. P. Provencio, and D. R. Tallant

Appl. Phys. Lett. 89, 241915 (2006); http://dx.doi.org/10.1063/1.2405847 (3 pages) | Cited 4 times

Online Publication Date: 13 December 2006

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Multiwall carbon nanotubes are grown via thermal chemical vapor deposition between temperatures of 630 and 830 °C using acetylene in nitrogen as the carbon source. This process is modeled using classical thermodynamics to explain the total carbon deposition as a function of time and temperature. An activation energy of 1.60 eV is inferred for nanotube growth after considering the carbon solubility term. Scanning electron microscopy shows growth with diameters increasing linearly with time. Transmission electron microscopy and Raman spectroscopy show multiwall nanotubes surrounded by a glassy-carbon sheath, which grows with increasing wall thickness as growth temperatures and times rise.
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81.07.De Nanotubes
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.A- Nucleation and growth
61.46.Fg Nanotubes
68.37.Hk Scanning electron microscopy (SEM) (including EBIC)
78.30.Na Fullerenes and related materials

Thin film interference in the optomechanical response of micromechanical silicon cantilevers

Paul R. Wilkinson and James K. Gimzewski

Appl. Phys. Lett. 89, 241916 (2006); http://dx.doi.org/10.1063/1.2405887 (3 pages) | Cited 3 times

Online Publication Date: 13 December 2006

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The mechanical response of uncoated silicon microcantilevers is shown to modulate as a function of incident wavelength. Cantilever motion is measured interferometrically, using phase sensitive detection in response to a mechanically chopped excitation source. Thin film interference modeling shows that the fraction of absorbed light within the cantilever varies periodically over the range of 450–1000 nm, in excellent agreement with the measurements. The results show that the optomechanical responsivity of these cantilevers can be tuned due to the effect via an appropriate selection of incident wavelength, incidence angle, lever thickness, and optical constants of the lever.
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07.10.Cm Micromechanical devices and systems
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Thermophysical and elastic properties of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass-forming alloys

G. J. Fan, M. Freels, H. Choo, P. K. Liaw, J. J. Z. Li, Won-Kyu Rhim, W. L. Johnson, P. Yu, and W. H. Wang

Appl. Phys. Lett. 89, 241917 (2006); http://dx.doi.org/10.1063/1.2408634 (3 pages) | Cited 22 times

Online Publication Date: 13 December 2006

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By employing a containerless high-temperature high-vacuum electrostatic levitation technique, the thermophysical properties, including the ratio between the specific heat capacity and the hemispherical total emissivity, the specific volume, and the viscosity, of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass (BMG)-forming liquids have been measured. Compared with Cu50Zr50, the improved glass-forming ability of (Cu50Zr50)95Al5 can be attributed to its dense liquid structure and its high value of viscosity. Additionally, the relationship between the viscosity of various BMG forming liquids at the melting temperature and the elastic properties of the corresponding glasses at room temperature will be compared.
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65.20.-w Thermal properties of liquids
61.25.Mv Liquid metals and alloys
66.20.-d Viscosity of liquids; diffusive momentum transport
64.70.P- Glass transitions of specific systems
64.70.Q- Theory and modeling of the glass transition
64.70.D- Solid-liquid transitions
81.40.Jj Elasticity and anelasticity, stress-strain relations

Energy absorption performance of steel tubes enhanced by a nanoporous material functionalized liquid

Xi Chen, Falgun B. Surani, Xinguo Kong, Venkata K. Punyamurtula, and Yu Qiao

Appl. Phys. Lett. 89, 241918 (2006); http://dx.doi.org/10.1063/1.2405852 (3 pages) | Cited 25 times

Online Publication Date: 14 December 2006

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The compressive behaviors of steel cells enhanced by a nanoporous silica functionalized liquid are investigated. As the empty space in the ductile cell is filled by an aqueous suspension of hydrophobic nanoporous silica gel, the work done by the compressive load along the axial direction can be dissipated not only through the ordinary cell-wall buckling but also via the extended yielding and the pressure-induced infiltration. As a result, the energy absorption efficiency, either on mass or on volumetric basis, is considerably improved.
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81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
82.70.Gg Gels and sols
82.70.Kj Emulsions and suspensions

Resistance and sheet resistance measurements using electron beam induced current

A. Czerwinski, M. Płuska, J. Ratajczak, A. Szerling, and J. Kątcki

Appl. Phys. Lett. 89, 241919 (2006); http://dx.doi.org/10.1063/1.2405886 (3 pages) | Cited 4 times

Online Publication Date: 14 December 2006

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A method for measurement of spatially uniform or nonuniform resistance in layers and strips, based on electron beam induced current (EBIC) technique, is described. High electron beam currents are used so that the overall resistance of the measurement circuit affects the EBIC signal. During the evaluation, the electron beam is scanned along the measured object, whose load resistance varies with the distance. The variation is compensated by an adjustable resistance within an external circuit. The method has been experimentally deployed for sheet resistance determination of buried regions of lateral confinements in semiconductor laser heterostructures manufactured by molecular beam epitaxy.
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06.30.Ka Basic electromagnetic quantities
84.37.+q Measurements in electric variables (including voltage, current, resistance, capacitance, inductance, impedance, and admittance, etc.)

Microtopologies in polymer surfaces by solvent drops in contact and noncontact mode

Guangfen Li, Nobert Höhn, and Karlheinz Graf

Appl. Phys. Lett. 89, 241920 (2006); http://dx.doi.org/10.1063/1.2404979 (3 pages) | Cited 4 times

Online Publication Date: 15 December 2006

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A method for the generation of protruded microstructures in polymer surfaces with an evaporating solvent drop, provided by a homemade syringe system, is presented. Either a concave surface topology is obtained by exposing the polymer surface to the vapor of a pendent solvent drop (noncontact mode) or a solvent drop is deposited on the polymer by moving the substrate up and down (contact mode). Thus a liquid bridge between syringe tip and polymer surface is formed and even convex microstructures can be generated for slow substrate retraction.
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68.47.Mn Polymer surfaces
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.08.-p Liquid-solid interfaces
61.41.+e Polymers, elastomers, and plastics
64.70.F- Liquid-vapor transitions

Optical characterization of intersubband transitions in ZnxCd1−xSe/Znx′Cdy′Mg1−x′−y′Se multiple quantum well structures by contactless electroreflectance

H. Lu, A. Shen, W. Charles, I. Yokomizo, M. C. Tamargo, K. J. Franz, C. Gmachl, and M. Muñoz

Appl. Phys. Lett. 89, 241921 (2006); http://dx.doi.org/10.1063/1.2405385 (3 pages) | Cited 5 times

Online Publication Date: 15 December 2006

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Contactless electroreflectance was measured at room temperature to characterize a wide range of the possible optical transitions in ZnxCd1−xSe/Znx′Cdy′Mg1−x′−y′Se multi-quantum-well structures grown by molecular beam epitaxy. Based on these measurements, the authors predict and then verify the anticipated intersubband transition energies. They investigate a representative Zn0.5Cd0.5Se/Zn0.20Cd0.19Mg0.61Se structure, for which the E1-E2 transition energy is predicted to be 178 meV (6.97 μm). Intersubband absorption using Fourier transform infrared spectroscopy exhibits a peak at 180 meV (6.89 μm), in excellent agreement with the contactless electroreflectance measurements.
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78.67.De Quantum wells
78.20.Jq Electro-optical effects
78.30.Fs III-V and II-VI semiconductors

Template-nonlithographic nanopatterning for site control growth of InGaN nanodots

Y. D. Wang, K. Y. Zang, S. J. Chua, and C. G. Fonstad

Appl. Phys. Lett. 89, 241922 (2006); http://dx.doi.org/10.1063/1.2405412 (3 pages) | Cited 3 times

Online Publication Date: 15 December 2006

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A site-control nucleation and growth approach for dense InGaN nanodots has been demonstrated on the surface of GaN using a nonlithographic nanopatterning technique by metal organic chemical vapor deposition. Shallow nanopore arrays with a depth of ∼ 15 nm are created by inductively coupled plasma etching in the GaN surface using anodic aluminum oxide films as etch masks. The nanopores are found to be the preferential sites for the InGaN nanodot formation. Uniform InGaN nanodot arrays with a density as high as 1010/cm2 as defined by the nanopores in GaN were observed on the surface. A strong photoluminescence (PL) emission peak near 2.8 eV is observed from the InGaN nanodots. The temperature dependence of PL shows the enhanced carrier localization with higher activation energy in the InGaN nanodots when compared to the InGaN thin layer grown simultaneously on the nonpatterned GaN surface.
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81.05.Ea III-V semiconductors
81.07.Bc Nanocrystalline materials
81.16.Rf Micro- and nanoscale pattern formation
78.55.Cr III-V semiconductors
61.46.Hk Nanocrystals
81.65.Cf Surface cleaning, etching, patterning

In situ identification of the metastable phase during solidification from the undercooled YFeO3 melt by fast x-ray diffractometry at 250 Hz

K. Nagashio, K. Kuribayashi, M. S. Vijaya Kumar, K. Niwata, T. Hibiya, A. Mizuno, M. Watanabe, and Y. Katayama

Appl. Phys. Lett. 89, 241923 (2006); http://dx.doi.org/10.1063/1.2408666 (3 pages) | Cited 10 times

Online Publication Date: 15 December 2006

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A time-resolved x-ray diffraction (XRD) experiment at 250 Hz using a synchrotron radiation source was carried out during the containerless solidification of ReFeO3 (Re = Y and Lu) in order to identify the metastable phase in situ. The metastable phase solidified primarily from the undercooled YFeO3 melt finally transformed to the stable orthorhombic YFeO3 phase during the short period of recalescence ( ∼ 0.035 s). Although the metastable phase could not be detected in the as-solidified sample by the powder XRD, the in situ diffraction pattern of the metastable phase in the YFeO3 system was consistent with that of the metastable hexagonal LuFeO3 phase.
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81.30.Fb Solidification
64.70.K- Solid-solid transitions
81.30.Hd Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder
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