Pulsed epitaxial lateral overgrowth of GaN by metalorganic vapour phase epitaxy

We report an inexpensive nanoscale patterning process for epitaxial lateral overgrowth (ELOG) in AlN layers grown by metal organic vapour phase epitaxy (MOVPE) on sapphire.

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Mg-enhanced lateral overgrowth of GaN on patterned GaN/sapphire substrate by selective Metal Organic Vapor Phase Epitaxy

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000922 ◽

1998 ◽

Vol 3 ◽

Cited By ~ 53

Author(s):

B. Beaumont ◽

M. Vaille ◽

G. Nataf ◽

A. Bouillé ◽

J.-C. Guillaume ◽

...

Keyword(s):

Vapour Phase ◽

Dielectric Films ◽

Vapour Phase Epitaxy ◽

Organic Vapor ◽

Lateral Overgrowth ◽

Metalorganic Vapour Phase Epitaxy ◽

Metal Organic ◽

Dislocations Density ◽

Image Position

Selective and lateral overgrowth by Metal Organics Vapour Phase Epitaxy (MOVPE) was carried out until coalescence to produce smooth and optically flat thick GaN layers. A GaN epitaxial layer is first grown using atmospheric pressure Metalorganic Vapour Phase Epitaxy on a {0001} Al2O3. substrate. Then a 30Å silicon nitride dielectric film is deposited in-situ by reaction of silane and ammonia to form a selective mask. Afterwards, the openings and the figures in the dielectric films are achieved using standard photolithographic technology. Stripes openings in the mask, revealing free GaN surface, are aligned in the 〈100〉 direction. Typical stripes spacing and width are 10 µm and 5 µm respectively. These patterned layers are further on used for epitaxial regrowth of GaN by MOVPE. The growth anisotropy and therefore the coalescence process is achieved by introducing (MeCp)2Mg in the vapour phase. A two-step process is reported which allows a dramatic reduction of threading dislocations density not only above the masked areas but also above the windows opened in the mask. With this process, very sharp bound exciton luminescence peaks are measured at low temperature in the overgrown GaN.

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GaN and AlN Layers Grown by Nano Epitaxial Lateral Overgrowth Technique on Porous Substrates

MRS Proceedings ◽

10.1557/proc-595-f99w2.7 ◽

1999 ◽

Vol 595 ◽

Cited By ~ 1

Author(s):

M. Mynbaeva ◽

A. Titkov ◽

A. Kryzhanovski ◽

A. Zubrilov ◽

V. Ratnikov ◽

...

Keyword(s):

Surface Morphology ◽

Defect Density ◽

Crack Density ◽

Vapour Phase ◽

Epitaxial Lateral Overgrowth ◽

Vapour Phase Epitaxy ◽

Nano Scale ◽

Density Reduction ◽

Lateral Overgrowth ◽

Porous Substrates

AbstractDefect density and stress reduction in heteroepitaxial GaN and AlN materials is one of the main issues in group III nitride technology. Recently, significant progress in defect density reduction in GaN layers has been achieved using lateral overgrowth technique. In this paper, we describe a novel technique based on nano-scale epitaxial lateral overgrowth.GaN layers were overgrown by hydride vapour phase epitaxy (HVPE) on porous GaN. Porous GaN was formed by anodization of GaN layers grown previously on SiC ŝubstrates. Pore's size was in nano-scale range.Thickness of overgrown layers ranged from 2 to 120 microns. It was shown that GaN layers overgrown on porous GaN have good surface morphology and high crystalline quality. The surface of overgrown GaN material was uniform and flat without any traces of porous structure. Raman spectroscopy measurements indicated that the stress in the layers grown on porous GaN was reduced down to 0.1 - 0.2 GPa, while the stress in the layers grown directly on 6H-SiC substrates remains at its usual level of about 1.3 GPa.Preliminary experiments were done on HVPE growth of AlN layer on porous substrates. Improvement of surface morphology and crack density reduction has been observed.

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Characterization of GaAs/AlGaAs quantum wells and quantum wires by chemical lattice imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171419 ◽

1994 ◽

Vol 52 ◽

pp. 736-737

Author(s):

A. Carlsson ◽

J.-O. Malm ◽

A. Gustafsson

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Quantum Wires ◽

Vapour Phase ◽

Quantitative Information ◽

Lattice Imaging ◽

Vapour Phase Epitaxy ◽

Metalorganic Vapour Phase Epitaxy ◽

High Resolution Images

In this study a quantum well/quantum wire (QW/QWR) structure grown on a grating of V-grooves has been characterized by a technique related to chemical lattice imaging. This technique makes it possible to extract quantitative information from high resolution images.The QW/QWR structure was grown on a GaAs substrate patterned with a grating of V-grooves. The growth rate was approximately three monolayers per second without growth interruption at the interfaces. On this substrate a barrier of nominally Al0.35 Ga0.65 As was deposited to a thickness of approximately 300 nm using metalorganic vapour phase epitaxy . On top of the Al0.35Ga0.65As barrier a 3.5 nm GaAs quantum well was deposited and to conclude the structure an additional approximate 300 nm Al0.35Ga0.65 As was deposited. The GaAs QW deposited in this manner turns out to be significantly thicker at the bottom of the grooves giving a QWR running along the grooves. During the growth of the barriers an approximately 30 nm wide Ga-rich region is formed at the bottom of the grooves giving a Ga-rich stripe extending from the bottom of each groove to the surface.

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Towards practical applications of quantum emitters in boron nitride

Scientific Reports ◽

10.1038/s41598-021-93802-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

M. Koperski ◽

K. Pakuła ◽

K. Nogajewski ◽

A. K. Dąbrowska ◽

M. Tokarczyk ◽

...

Keyword(s):

Optical Properties ◽

Boron Nitride ◽

Vapour Phase ◽

Emission Characteristics ◽

Vapour Phase Epitaxy ◽

Practical Applications ◽

Metalorganic Vapour Phase Epitaxy ◽

Polydimethylsiloxane Films ◽

Background Luminescence ◽

Quantum Emitters

AbstractWe demonstrate quantum emission capabilities from boron nitride structures which are relevant for practical applications and can be seamlessly integrated into a variety of heterostructures and devices. First, the optical properties of polycrystalline BN films grown by metalorganic vapour-phase epitaxy are inspected. We observe that these specimens display an antibunching in the second-order correlation functions, if the broadband background luminescence is properly controlled. Furthermore, the feasibility to use flexible and transparent substrates to support hBN crystals that host quantum emitters is explored. We characterise hBN powders deposited onto polydimethylsiloxane films, which display quantum emission characteristics in ambient environmental conditions.

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