Homo- and Hetero-Epitaxial Gallium Nitride Grown by Molecular Beam Epitaxy

Various methods have been used to initiate growth by Molecular Beam Epitaxy (MBE) of GaN on sapphire, or other substrates, but there is always a problem with morphology and with a high defect density which results in the formation of a sub-grain boundary structure. We show that by using, homo-epitaxial growth on properly prepared bulk GaN substrates, combined with high temperature growth, we obtain a significant improvement in surface morphology. Growth at sufficiently high temperature leads to a rapid smoothing of the surface and to almost atomically flat surfaces over relatively large areas. Multi-Quantum Well structures grown on such GaN epitaxial films are dislocation free with abrupt interfaces.

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Homo- and Hetero-Epitaxial Gallium Nitride Grown by Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-537-g4.11 ◽

1998 ◽

Vol 537 ◽

Author(s):

C.T. Foxon ◽

T.S. Cheng ◽

D. Korakakis ◽

S.V. Novikov ◽

R.P. Campion ◽

...

Keyword(s):

High Temperature ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Defect Density ◽

Boundary Structure ◽

Quantum Well Structures ◽

Flat Surfaces ◽

Grain Boundary Structure ◽

Bulk Gan ◽

Atomically Flat

AbstractVarious methods have been used to initiate growth by Molecular Beam Epitaxy (MBE) of GaN on sapphire, or other substrates, but there is always a problem with morphology and with a high defect density which results in the formation of a sub-grain boundary structure. We show that by using, homo-epitaxial growth on properly prepared bulk GaN substrates, combined with high temperature growth, we obtain a significant improvement in surface morphology. Growth at sufficiently high temperature leads to a rapid smoothing of the surface and to almost atomically flat surfaces over relatively large areas. Multi-Quantum Well structures grown on such GaN epitaxial films are dislocation free with abrupt interfaces.

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High-Temperature Growth of GaN Nanowires by Molecular Beam Epitaxy: Toward the Material Quality of Bulk GaN

Crystal Growth & Design ◽

10.1021/acs.cgd.5b00690 ◽

2015 ◽

Vol 15 (8) ◽

pp. 4104-4109 ◽

Cited By ~ 20

Author(s):

Johannes K. Zettler ◽

Christian Hauswald ◽

Pierre Corfdir ◽

Mattia Musolino ◽

Lutz Geelhaar ◽

...

Keyword(s):

High Temperature ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Temperature Growth ◽

Material Quality ◽

Gan Nanowires ◽

Bulk Gan

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High‐temperature observation of heavy‐hole and light‐hole excitons in InGaAs/InP multiple quantum well structures grown by metalorganic molecular beam epitaxy

Applied Physics Letters ◽

10.1063/1.97922 ◽

1987 ◽

Vol 50 (18) ◽

pp. 1243-1245 ◽

Cited By ~ 50

Author(s):

Yoshihiro Kawaguchi ◽

Hajime Asahi

Keyword(s):

High Temperature ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Heavy Hole ◽

Multiple Quantum Well ◽

Light Hole ◽

Multiple Quantum ◽

Quantum Well Structures ◽

Temperature Observation ◽

Metalorganic Molecular Beam Epitaxy

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The effect of growth condition on the structure of 2H – AlN films deposited on Si(111) by plasma-assisted molecular beam epitaxy

Journal of Materials Research ◽

10.1557/jmr.1999.0275 ◽

1999 ◽

Vol 14 (5) ◽

pp. 2036-2042 ◽

Cited By ~ 20

Author(s):

U. Kaiser ◽

P. D. Brown ◽

I. Khodos ◽

C. J. Humphreys ◽

H. P. D. Schenk ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Film Surface ◽

Interface Structure ◽

Flat Surfaces ◽

Si Substrates ◽

Nitridation Time ◽

Transmission Electron ◽

Atomically Flat ◽

Film Defect

The effects of substrate cleaning, nitridation time, and substrate temperature in the range 800–1000 °C on the microstructure of AlN/Si(111) films grown by simultaneous plasma-assisted molecular beam epitaxy have been investigated. It has been demonstrated, using a combination of conventional and high-resolution transmission electron microscopy, that the interface structure, the film defect structure, and the film surface roughness are strongly related. The formation of single crystal 2H–AlN films with atomically flat surfaces occurs at 800 °C for conditions of 2.5 nm/min growth rate on very pure, atomically flat Si substrates.

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Growth of “colossal” magnetoresistance heterostructures by molecular beam epitaxy

MRS Proceedings ◽

10.1557/proc-602-9 ◽

1999 ◽

Vol 602 ◽

Cited By ~ 1

Author(s):

J. O'Donnell ◽

A. E. Andrus ◽

S. Oh ◽

E. Colla ◽

M. Warusawithana ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Colossal Magnetoresistance ◽

Molecular Beam ◽

Residual Resistivity ◽

Bulk Single Crystal ◽

Heteroepitaxial Growth ◽

Flat Surfaces ◽

Narrow Region ◽

Slight Excess ◽

Atomically Flat

We discuss the heteroepitaxial growth of La1−xSrxMnO3 films and CaTiO3 insulating barriers by molecular beam epitaxy. We find that the surface morphology and residual resistivity of the manganite electrodes is critically dependent on the film stoichiometry. The most important parameter is the concentration of La+Sr (cubic perovskite A-site cations) to that of Mn (B-site cation). If La+Sr is supplied in slight excess, the films grow with atomically flat surfaces, but the residual resistivity at 4.2K is high (as high as 6500 µΩ-cm), and Curie temperature (Tc) low (<300 K). If Mn is supplied in slight excess, the films have high Tc (370 K) and residual resistivity (35 µΩ-cm) better than bulk single crystal values, but the surface is no longer atomically flat. There appears to be a very narrow region of phase space where it is possible to have low resistivity, high Tc films with atomically flat surfaces. This is precisely where one would like to place heterostructure devices.

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Molecular Beam Epitaxy of Single Crystal Colossal Magneto-Resistive Material

MRS Proceedings ◽

10.1557/proc-401-467 ◽

1995 ◽

Vol 401 ◽

Author(s):

J. N. Eckstein ◽

I. Bozovic ◽

M. Rzchowski ◽

J. O'donnell ◽

B. Hinaus ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Atomic Layer ◽

Growth Conditions ◽

Dislocation Network ◽

Layer By Layer ◽

Flat Surfaces ◽

Low Field ◽

Resistive Material ◽

Atomically Flat

AbstractWe have grown films of (LaSr)MnO3 (LSMO) and (LaCa)MnO3 (LCMO) using atomic layer-by-layer molecular beam epitaxy (ALL-MBE). Depending on growth conditions, substrate lattice constant and the exact cation stoichiometry, the films are either pseudomorphic or strain relaxed. The pseudomorphic films show atomically flat surfaces, with a unit cell terrace structure that is a replica of that observed on the slightly vicinal substrates, while the strain relaxed films show bumpy surfaces correlated with a dislocation network. All films show tetragonal structure and exhibit anisotropic magnetoresistance, with a low field response, (1/R)(dR/dH) as large as 5 T−1.

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An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010648x ◽

1988 ◽

Vol 46 ◽

pp. 884-885

Author(s):

D. Loretto ◽

J. M. Gibson ◽

S. M. Yalisove ◽

R. T. Tung

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Defect Density ◽

High Vacuum ◽

Ultra High Vacuum ◽

Ex Situ ◽

Metal Base ◽

In Situ Experiments ◽

Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

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