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25 Dec 2000

Volume 77, Issue 26, pp. 4247-4436

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Grazing-incidence diffraction strain analysis of a laterally-modulated multiquantum well system produced by focused-ion-beam implantation

J. Grenzer, N. Darowski, U. Pietsch, A. Daniel, S. Rennon, J. P. Reithmaier, and A. Forchel

Appl. Phys. Lett. 77, 4277 (2000); http://dx.doi.org/10.1063/1.1332410 (3 pages) | Cited 6 times

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Focused Ga+ ion beam implantation was used to define a laterally periodic modulation of the electronic band gap in a GaAs/Ga0.97In0.03As/Al0.2Ga0.8As/GaAs [001] multiquantum well structure. The samples were investigated as-implanted and after a rapid thermal annealing (60 s at 650 and 800 °C) by means of x-ray grazing-incidence diffraction. The method provides a separate inspection of the induced strain and the damage profiles as a function of depth below the sample surface. For samples with an ion dose of 5×1013 cm−2, we found a nearly uniform lateral strain amplitude of about 2×10−3 up to the maximum information depth of about 500 nm. It was accompanied by the appearance of structural defects. Rapid thermal annealing at 650 °C has reduced the strain amplitude by a factor of five as well as the density of volume defects. The maximum strain amplitude were found in a depth of about 100 nm. After rapid thermal annealing at 800 °C, the strain has disappeared. © 2000 American Institute of Physics.
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61.72.uj III-V and II-VI semiconductors
68.60.Bs Mechanical and acoustical properties
42.82.Cr Fabrication techniques; lithography, pattern transfer
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.J- Point defects and defect clusters

Preferential amorphization and defect annihilation at nanocavities in silicon during ion irradiation

J. S. Williams, Xianfang Zhu, M. C. Ridgway, M. J. Conway, B. C. Williams, F. Fortuna, M.-O. Ruault, and H. Bernas

Appl. Phys. Lett. 77, 4280 (2000); http://dx.doi.org/10.1063/1.1334355 (3 pages) | Cited 18 times

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Si containing a band of nanocavities has been irradiated with Si+ ions at elevated temperatures to study interactions of irradiation-induced defects with open volume defects. For irradiation at 100 °C, nanocavities are shown to be preferential nucleation sites for amorphization. It is proposed that this behavior occurs to minimize the local free energy, whereby less dense amorphous Si is free to expand into the cavity open volume. Furthermore, for irradiation at 300 °C, cavities are very efficient sinks for Si interstitials during irradiation, leaving a region denuded of interstitial-based clusters surrounding each nanocavity. © 2000 American Institute of Physics.
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61.80.Jh Ion radiation effects
61.82.Fk Semiconductors
61.72.J- Point defects and defect clusters

Temperature dependence of the surface plasmon resonance of Au/SiO2 nanocomposite films

Dan Dalacu and Ludvik Martinu

Appl. Phys. Lett. 77, 4283 (2000); http://dx.doi.org/10.1063/1.1334362 (3 pages) | Cited 14 times

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The optical response of Au/SiO2 nanocomposite films at temperatures spanning the transition to the liquid state has been measured. The change in the optical constants of gold from those corresponding to the crystalline material to those of the liquid occurs gradually and at temperatures below the bulk melting point. The similarity of the temperature-induced changes in the Au interband absorption edge to that observed with decreasing particle size suggests that a gradual transition to the liquid phase also occurs in small particles. © 2000 American Institute of Physics.
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61.46.-w Structure of nanoscale materials
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
64.70.D- Solid-liquid transitions

Atom-scale optical determination of Si-oxide layer thickness during layer-by-layer oxidation: Theoretical study

Takashi Nakayama and Misao Murayama

Appl. Phys. Lett. 77, 4286 (2000); http://dx.doi.org/10.1063/1.1334647 (3 pages) | Cited 18 times

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Optical anisotropy spectra of SiO2/Si(001) interfaces were theoretically investigated based on the sp3s∗ tight-binding calculation. In the spectra, we found three types of optical transitions originating from the E1 and E2 transitions of bulk Si, the interface Si–Si bonds, and the dangling-bond states at the interface. It was shown that the sign of these transitions oscillates during the layer-by-layer oxidation, which indicates that by counting the oscillation one can determine the layer thickness of oxidized Si layers in an atomic scale. © 2000 American Institute of Physics.
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81.65.Mq Oxidation
73.20.Hb Impurity and defect levels; energy states of adsorbed species
78.40.-q Absorption and reflection spectra: visible and ultraviolet
71.15.Ap Basis sets (LCAO, plane-wave, APW, etc.) and related methodology (scattering methods, ASA, linearized methods, etc.)

Preparation and single molecule structure of electroactive polysilane end-grafted on a crystalline silicon surface

Kazuaki Furukawa and Keisuke Ebata

Appl. Phys. Lett. 77, 4289 (2000); http://dx.doi.org/10.1063/1.1334652 (3 pages) | Cited 7 times

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Electrically active polysilanes of poly(methylphenylsilane) (PMPS) and poly[bis(p-n-butylphenyl)silane] (PBPS), which are, respectively, known as a good hole transporting material and a near-ultraviolet electroluminescent material, are end-grafted directly on a crystalline silicon surface. The single polysilane molecules are clearly distinguished one from the other on the surface by means of atomic force microscopy observations. End-grafted single molecules of PMPS are observed as dots while end-grafted PBPS appear as worms extending for more than 100 nm on the crystalline silicon surface. © 2000 American Institute of Physics.
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61.41.+e Polymers, elastomers, and plastics
72.80.Le Polymers; organic compounds (including organic semiconductors)
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials
78.40.Me Organic compounds and polymers
78.40.Fy Semiconductors

Material properties of bulk InGaAs and InAlAs/InGaAs heterostructures grown on (111)B and (111)B misoriented by 1° towards 〈211〉 InP substrates

W. Yeo, R. Dimitrov, W. J. Schaff, and L. F. Eastman

Appl. Phys. Lett. 77, 4292 (2000); http://dx.doi.org/10.1063/1.1332836 (3 pages)

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High-quality bulk InGaAs and InAlAs/InGaAs heterostructures have been grown on InP substrates with different orientation using molecular-beam epitaxy. It was found that the electrical and structural properties were strongly dependent on growth temperature and substrate misorientation. The electrical and structural properties of the film were investigated by high-resolution x-ray diffraction, Nomarski microscope, and Hall measurements. Full-width at half-maximum of 380 arcsec for bulk InGaAs on (111)B and 70 arcsec on (111)B misoriented by 1° towards 〈211〉 InP substrates were measured by x-ray diffraction. The room temperature electron Hall mobility for bulk InGaAs of 5100 cm2/V s, doped with Si concentration at the mid-1017/cm3, and two-dimensional electron gas mobility of 11 200 cm2/V s, and sheet density of 3.0×1012/cm2 for InAlAs/InGaAs heterostructures on (111)B misoriented by 1° towards 〈211〉 InP substrates were achieved. © 2000 American Institute of Physics.
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73.61.Ey III-V semiconductors
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
81.05.Ea III-V semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.-a Thin film structure and morphology
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
77.65.Ly Strain-induced piezoelectric fields

Scanning thermal microscopy of carbon nanotubes using batch-fabricated probes

Li Shi, Sergei Plyasunov, Adrian Bachtold, Paul L. McEuen, and Arunava Majumdar

Appl. Phys. Lett. 77, 4295 (2000); http://dx.doi.org/10.1063/1.1334658 (3 pages) | Cited 47 times

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We have designed and batch-fabricated thin-film thermocouple cantilever probes for scanning thermal microscopy (SThM). Here, we report the use of these probes for imaging the phonon temperature distribution of electrically heated carbon-nanotube (CN) circuits. The SThM images reveal possible heat dissipation mechanisms in CN circuits. The experiments also demonstrate that heat flow through the tip-sample nanoscale junction under ambient conditions is dominated by conduction through a liquid film bridging the two surfaces. With the spatial resolution limited by tip radius to about 50 nm, SThM now offers the promising prospects of studying electron-phonon interactions and phonon transport in low dimensional nanostructures. © 2000 American Institute of Physics.
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63.22.-m Phonons or vibrational states in low-dimensional structures and nanoscale materials
63.20.K- Phonon interactions
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
61.46.-w Structure of nanoscale materials

Atomic force microscopy study of plastic deformation and interfacial sliding in Al thin film: Si substrate systems due to thermal cycling

M. W. Chen and I. Dutta

Appl. Phys. Lett. 77, 4298 (2000); http://dx.doi.org/10.1063/1.1332098 (3 pages) | Cited 15 times

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A method is proposed to measure the plastic deformation of thin metallic films on Si substrates induced by thermal cycling. The cross-sectional profiles of pattern-grown square Al films with a thickness of ∼ 250 nm and a size of ∼ 6 μm×6 μm were measured before and after thermal cycling by employing an atomic force microscope. With the assistance of statistical analysis, the change in the size and shape of the thin films were determined. Based on theoretical considerations, the thermal cycling deformation of thin films is attributed to creep and plasticity effects, accommodated by diffusion-controlled interfacial sliding. © 2000 American Institute of Physics.
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68.60.Bs Mechanical and acoustical properties
68.35.Gy Mechanical properties; surface strains
85.40.Ls Metallization, contacts, interconnects; device isolation

Optical characterization of relaxation processes in nitrogen-doped ZnSe layers

L. Worschech, W. Ossau, J. Nürnberger, W. Faschinger, and G. Landwehr

Appl. Phys. Lett. 77, 4301 (2000); http://dx.doi.org/10.1063/1.1334913 (3 pages)

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Linear polarization of the nitrogen acceptor bound exciton I1N luminescence, which reflects the anisotropic strain relief of the ZnSe lattice, is exploited to monitor two independent relaxation processes in nitrogen-doped ZnSe films. An inhomogeneous vertical strain profile is identified by a maximum in-plane polarization when 800 nm of the sample surface are removed. After exposure of nitrogen-doped ZnSe films to intense light, an isotropic strain relief is observed. The I1N peak position is shifted to lower energies, whereas the anisotropic polarization remains constant. © 2000 American Institute of Physics.
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78.66.Hf II-VI semiconductors
78.55.Et II-VI semiconductors
68.60.Bs Mechanical and acoustical properties
62.40.+i Anelasticity, internal friction, stress relaxation, and mechanical resonances
71.35.Gg Exciton-mediated interactions
71.55.Gs II-VI semiconductors

Growth of nanocrystalline diamond films by biased enhanced microwave plasma chemical vapor deposition: A different regime of growth

T. Sharda, M. Umeno, T. Soga, and T. Jimbo

Appl. Phys. Lett. 77, 4304 (2000); http://dx.doi.org/10.1063/1.1333399 (3 pages) | Cited 31 times

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Hard and smooth nanocrystalline diamond films are grown on mirror polished silicon substrates by biased enhanced growth (BEG) in microwave plasma chemical vapor deposition at lower temperatures. Hardness of the films varies with deposition condition and can be defined by the relative concentration of nanocrystalline diamond in the films, as measured by the Raman intensity ratio of the feature near 1150 cm−1 to the intensity of graphitic G band. The hardness of the films approaches the hardness of diamond at conditions giving maximum concentration of nanocrystalline diamond while still having a low amount of stress (1–2 GPa). A different regime of growth appears to exist in the films deposited by the BEG process that may, however, be a combination of surface and subsurface processes. © 2000 American Institute of Physics.
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81.05.ub Fullerenes and related materials
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
61.46.-w Structure of nanoscale materials
68.60.Bs Mechanical and acoustical properties
78.30.Am Elemental semiconductors and insulators

Interaction of a Ti-capped Co thin film with Si3N4

Hua Li, Hugo Bender, Thierry Conard, Karen Maex, Anton Gutakovskii, Jozef Van Landuyt, and Ludo Froyen

Appl. Phys. Lett. 77, 4307 (2000); http://dx.doi.org/10.1063/1.1329329 (3 pages) | Cited 1 time

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The reaction of a Ti (8 nm) capped Co film (15 nm) with a Si3N4 layer (150 nm) is studied after rapid thermal annealing at 660 °C for 120 s in a N2 ambient. X-ray photoelectron spectroscopy, transmission electron microscopy, electron energy-loss spectroscopy, and Auger electron spectroscopy are used to study the reaction products. Combining the results of the different analyses yields a layer stack consisting of: TiO2/TiO/unreacted Co/(Ti,Co)2N/Co2Si, followed by amorphous Si3N4. The reaction mechanisms are discussed. Conclusions concerning the risk for degradation of nitride spacers in advanced devices are drawn. © 2000 American Institute of Physics.
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73.61.Ng Insulators
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
68.35.Fx Diffusion; interface formation
61.72.Cc Kinetics of defect formation and annealing
79.60.Jv Interfaces; heterostructures; nanostructures
73.40.Ns Metal-nonmetal contacts

Phase separation in metalorganic vapor-phase epitaxy AlxGa(1−x)N films deposited on 6H–SiC

P. Vennéguès and H. Lahrèche

Appl. Phys. Lett. 77, 4310 (2000); http://dx.doi.org/10.1063/1.1336166 (3 pages) | Cited 12 times

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The microstructure of AlxGa(1−x)N films deposited on 6H–SiC substrates by metalorganic vapor-phase epitaxy is studied by transmission electron microscopy and energy-dispersive x-ray analysis. It is shown that in the first step of the growth (three-dimensional), the deposit is constituted of a thin Al-rich AlGaN wetting layer covering the substrate surmounted by pure GaN islands. In a second step, a homogeneous AlxGa(1−x)N film, with nominal Al concentration, is deposited and smoothing is observed. The results of the high-resolution transmission electron microscopy about the strain state of the different parts of the deposit indicate that the driving force for the phase separation phenomena is the decrease of the interfacial energy due to the low mismatch between Al-rich AlGaN and 6H–SiC (1% for pure AlN). © 2000 American Institute of Physics.
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68.55.-a Thin film structure and morphology
81.15.Kk Vapor phase epitaxy; growth from vapor phase
64.75.-g Phase equilibria
85.30.Kk Junction diodes
81.05.Ea III-V semiconductors

Fabrication of highly ordered porous structures

Q.-B. Meng, Z.-Z. Gu, O. Sato, and A. Fujishima

Appl. Phys. Lett. 77, 4313 (2000); http://dx.doi.org/10.1063/1.1332109 (3 pages) | Cited 22 times

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We describe a simple method for the fabrication of highly ordered porous structures. That is, utilizing capillary forces, ultrafine particles are directly used to assemble themselves in the voids of template while the template is being assembled. The highly ordered porous structures with larger area and uniform orientation can be produced after removing the template. The majority of the single domains with uniform orientation prepared can reach 0.1 mm2 in area. Scanning electron microscope images and transmission spectrum of these samples have confirmed the success of this simple method. © 2000 American Institute of Physics.
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81.05.Rm Porous materials; granular materials
61.43.Gt Powders, porous materials
78.66.Vs Fine-particle systems
78.40.Pg Disordered solids

Strong interface-induced changes on the numerical calculated Raman scattering in Si/3C–SiC superlattices

E. F. Bezerra, V. N. Freire, A. G. Souza Filho, J. Mendes Filho, V. Lemos, Y. Ikoma, F. Watanabe, and T. Motooka

Appl. Phys. Lett. 77, 4316 (2000); http://dx.doi.org/10.1063/1.1328763 (3 pages) | Cited 1 time

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Raman spectra of (3C–SiC)8−δ/(3C–SiC0.5Si0.5)δ/(Si)8−δ/(3C–SiC0.5Si0.5)δ superlattices with interfacial transition regions of thickness δ varying from one to three monolayers are calculated. It is shown that severe frequency shifts (up to −86 cm−1) and the flattening of the folded optical phonons dispersion curves are due to the interfacial regions, strongly affecting the Raman spectrum in consequence. With increasing interface thickness, the Raman peaks are enhanced in the middle frequency range. These effects are mainly attributed to localization of atomic displacements at the Si/3C–SiC or the 3C–SiC/Si interfacial transition regions. © 2000 American Institute of Physics.
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78.66.Li Other semiconductors
78.30.Hv Other nonmetallic inorganics
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
78.66.Db Elemental semiconductors and insulators
78.30.Am Elemental semiconductors and insulators

Inversion domains triggering recovery of luminescence uniformity in epitaxially lateral overgrown thick GaN film

Chinkyo Kim, Jaehyung Yi, Min Yang, Minhong Kim, Jina Jeon, Sungwon Khym, Meoungwhan Cho, Yoonho Choi, Shi-Jong Leem, and Seon Tai Kim

Appl. Phys. Lett. 77, 4319 (2000); http://dx.doi.org/10.1063/1.1332985 (3 pages) | Cited 2 times

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A 150 μm-thick GaN layer was grown by halide vapor phase epitaxy utilizing selective lateral overgrowth on a SiO2-prepatterned sapphire substrate. A series of optically active regions above the SiO2 mask was observed in cross sectional monochromatic cathodoluminescence images taken at 367 nm. These bright regions were, however, consistently terminated by triangular shaped domains at 60 to 80 μm thickness, leaving no sign of luminescence nonuniformity beyond the thickness. In conjunction with the recent results on the characteristics of inversion domains in GaN, we proposed that these triangular regions might be inversion domains. © 2000 American Institute of Physics.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
68.55.-a Thin film structure and morphology
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Direct evidence for 8-interstitial-controlled nucleation of extended defects in c-Si

F. Schiettekatte, S. Roorda, R. Poirier, M. O. Fortin, S. Chazal, and R. Héliou

Appl. Phys. Lett. 77, 4322 (2000); http://dx.doi.org/10.1063/1.1336163 (3 pages) | Cited 2 times

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The areal density of extended defects in P-implanted and annealed Si is observed to increase with ion dose to the power 8. A simple model based on Poisson statistics applied to point defects created during ion implantation shows that such a dependence corresponds to enhanced stability of interstitial clusters consisting of at least eight interstitial atoms, and it implies an interstitial “clustering” radius of 0.8 nm. The direct observation of n = 8 confirms the curious behavior observed earlier in transient-enhanced diffusion of B in Si, and provides a quantitative explanation of the threshold dose for the formation of extended defects in ion-implanted Si. © 2000 American Institute of Physics.
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61.72.Nn Stacking faults and other planar or extended defects
61.72.J- Point defects and defect clusters
61.72.uf Ge and Si
61.82.Fk Semiconductors

Grain boundary filtration by selective nucleation and solid phase epitaxy of Ge through planar constrictions

Hiroshi Tanabe, Claudine M. Chen, and Harry A. Atwater

Appl. Phys. Lett. 77, 4325 (2000); http://dx.doi.org/10.1063/1.1333682 (3 pages) | Cited 3 times

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We have proposed and experimentally demonstrated a grain boundary filtration technique for unseeded fabrication of single grain semiconductor films on amorphous substrates by using patterned P-doped amorphous Ge films with In-induced selective nucleation and solid phase epitaxy. The patterns consist of a small Ge island seed region including a deposited metal selective nucleation site, a narrow seed region, and a single grain region consisting of a main rectangular island. Transmission electron microscopy revealed lateral epitaxy initiated at the edge of the selective nucleation site and the grain selection process through the narrow seed selection region produced only one grain orientation at the entrance of the main island. Single grain regions as large as 100 μm2 with only a few low-angle boundaries were formed at 400 °C without spontaneous nucleation. © 2000 American Institute of Physics.
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81.15.Np Solid phase epitaxy; growth from solid phases
61.72.Mm Grain and twin boundaries
81.05.Cy Elemental semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Spherical SiGe quantum dots prepared by thermal evaporation

Yu-Cheng Liao, Shih-Yen Lin, Si-Chen Lee, and Chih-Ta Chia

Appl. Phys. Lett. 77, 4328 (2000); http://dx.doi.org/10.1063/1.1334649 (2 pages) | Cited 6 times

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SiGe alloy quantum dots with spherical shape have been synthesized by the thermal evaporation method. The shape and structure of these dots have been investigated. Transmission electron microscopy images show that they have an average diameter of about 15 nm, and their cores are crystalline. The composition of these dots could be extracted from the Raman peak position of the silicon TO phonon. © 2000 American Institute of Physics.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
78.30.Hv Other nonmetallic inorganics
78.66.Fd III-V semiconductors
63.20.D- Phonon states and bands, normal modes, and phonon dispersion

Compressive strength of synthetic diamond grits containing metallic nanoparticles

J. H. P. Watson, Z. Li, and A. M. Hyde

Appl. Phys. Lett. 77, 4330 (2000); http://dx.doi.org/10.1063/1.1334352 (2 pages) | Cited 3 times

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Synthetic diamonds made by high-temperature and high-pressure synthesis using an Fe–Co solvent/catalyst leave nanoparticles of the solvent/catalyst within the diamond matrix. These nanoparticles strongly affect the magnetic properties of the diamond. The magnetization versus field was compatible with the response of superparamagnetic particles. The mean size and separation of the inclusions were calculated. The inclusion size was found to be constant to within 10%, whereas the saturation magnetization varied by a factor of 100. A transmission electron microscope image of a single inclusion from a Fe–Co/diamond grit showed a dark, iron-rich core surrounded by a halo of material of intermediate contrast to the lighter diamond matrix. The size of the core is consistent with the magnetization measurements while the halo is of similar size to that determined by small-angle neutron scattering. The compressive strength increased linearly with the inclusion separation. © 2000 American Institute of Physics.
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81.05.ub Fullerenes and related materials
81.40.Lm Deformation, plasticity, and creep
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
61.72.Qq Microscopic defects (voids, inclusions, etc.)
62.20.F- Deformation and plasticity
75.50.Tt Fine-particle systems; nanocrystalline materials

Amorphization and anisotropic fracture dynamics during nanoindentation of silicon nitride: A multimillion atom molecular dynamics study

Phillip Walsh, Rajiv K. Kalia, Aiichiro Nakano, Priya Vashishta, and Subhash Saini

Appl. Phys. Lett. 77, 4332 (2000); http://dx.doi.org/10.1063/1.1328371 (3 pages) | Cited 16 times

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Molecular dynamics simulations of nanoindentation of 10 million atom α-Si3N4 films using a rigid indenter are reported. Local pressure distributions and configuration images of the plastically deformed region are presented. Residual tensile pressures correspond to voids and cracks that separate regions of compacted, plastically deformed material and elastically recovered crystalline material. Structural analysis shows that pile-up material on the surface and deformed material under the indenter is amorphous. With this indenter geometry, Si3N4 deforms primarily by amorphization, which is arrested by cracking at the indenter corners and piling-up of material along the indenter sides. Indentation fracture exhibits anisotropic behavior consistent with the orientation-dependent fracture toughness values. © 2000 American Institute of Physics.
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68.60.Bs Mechanical and acoustical properties
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
62.20.Qp Friction, tribology, and hardness
61.43.Er Other amorphous solids
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
61.72.Qq Microscopic defects (voids, inclusions, etc.)
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
68.35.Gy Mechanical properties; surface strains
61.43.Bn Structural modeling: serial-addition models, computer simulation

Magnetoluminescence studies in InGaP alloys

J. Zeman, G. Martinez, K. K. Bajaj, I. Krivorotov, and K. Uchida

Appl. Phys. Lett. 77, 4335 (2000); http://dx.doi.org/10.1063/1.1334648 (3 pages) | Cited 8 times

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We have measured both the diamagnetic shift and the linewidth of an excitonic transition in In0.48Ga0.52P as a function of magnetic field up to 22 T at 4.2 K using photoluminescence spectroscopy. The sample was grown on a GaAs substrate using low-pressure metalorganic vapor phase epitaxy at 700 °C. The substrate was misoriented by 15° from [001] towards [011] direction. We find that the variations of both the diamagnetic shift and the linewidth with magnetic field are about one half of those reported earlier [E. D. Jones, R. P. Schneider, Jr., S. M. Lee, and K. K. Bajaj, Phys. Rev. B 46, 7225 (1992)] in a In0.48Ga0.52P sample grown with only 2° misorientation and also those calculated using a free exciton model. We suggest that this behavior may be due to the fact that our sample was grown with much larger misorietation. We have calculated both of these variations using a model in which we assume that in this sample the hole is completely localized and find an excellent agreement with the observed data. © 2000 American Institute of Physics.
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78.55.Cr III-V semiconductors
78.20.Ls Magneto-optical effects
71.35.Ji Excitons in magnetic fields; magnetoexcitons
78.66.Fd III-V semiconductors
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