Improvement of optical quality of semipolar  (112¯2) GaN on m-plane sapphire by in-situ epitaxial lateral overgrowth

ABSTRACTSynchrotron white beam x-ray topography techniques, in section and large-area transmission modes, have been applied to the evaluation of ELOG GaN on A12O3. Using the openings in 100 nm thick SiO2 windows, a new GaN growth took place, which resulted in typical overgrowth thicknesses of 6.8 μm. Measurements on the recorded Laue patterns indicate that the misorientation of GaN with respect to the sapphire substrate (excluding a 30° rotation between them) varies considerably along various crystalline directions, reaching a maximum of a ∼0.66° rotation of the (0001) plane about the [01•1] axis. This is ∼3% smaller than the misorientation measured in the non-ELOG reference, which reached a maximum of 0.68°. This misorientation varies measurably as the stripe or window dimensions are changed. The quality of the ELOG epilayers is improved when compared to the non- ELOG samples, though some local deviations from lattice coherence were observed. Long range and large-scale (order of 100 μm long) strain structures were observed in all multi quantum well epilayers.

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Epitaxial lateral overgrowth of GaN on sapphire substrates using in-situ carbonized photoresist mask

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2011.01.097 ◽

2011 ◽

Vol 326 (1) ◽

pp. 200-204 ◽

Cited By ~ 6

Author(s):

Sang-il Kim ◽

Bumjoon Kim ◽

Samseok Jang ◽

A-young Kim ◽

Jihun Park ◽

...

Keyword(s):

Epitaxial Lateral Overgrowth ◽

Sapphire Substrates ◽

Lateral Overgrowth ◽

Photoresist Mask

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Improved Crystalline Quality of AlN by Epitaxial Lateral Overgrowth Using Two-Phase Growth Method for Deep-Ultraviolet Stimulated Emission

IEEE Photonics Journal ◽

10.1109/jphot.2016.2614102 ◽

2016 ◽

Vol 8 (5) ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Xiang Chen ◽

Jianchang Yan ◽

Yun Zhang ◽

Yingdong Tian ◽

Yanan Guo ◽

...

Keyword(s):

Stimulated Emission ◽

Epitaxial Lateral Overgrowth ◽

Crystalline Quality ◽

Phase Growth ◽

Two Phase ◽

Lateral Overgrowth ◽

Growth Method ◽

Deep Ultraviolet

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Comparison of optical quality metrics to predict subjective quality of vision after laser in situ keratomileusis

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2008.12.039 ◽

2009 ◽

Vol 35 (5) ◽

pp. 846-855 ◽

Cited By ~ 17

Author(s):

Jens Bühren ◽

Konrad Pesudovs ◽

Tim Martin ◽

Anja Strenger ◽

Geunyoung Yoon ◽

...

Keyword(s):

Optical Quality ◽

Quality Metrics ◽

Subjective Quality ◽

Laser In Situ Keratomileusis ◽

Quality Of Vision

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AlxGa1−xN GROWTH BY Si/N TREATMENT OF SAPPHIRE SUBSTRATE: COMPARISON WITH OTHERS GROWTH TECHNIQUES

Surface Review and Letters ◽

10.1142/s0218625x19501166 ◽

2019 ◽

Vol 27 (03) ◽

pp. 1950116

Author(s):

I. HALIDOU ◽

A. TOURÉ ◽

B. EL JANI

Keyword(s):

Sapphire Substrate ◽

Three Dimensional ◽

Epitaxial Lateral Overgrowth ◽

Treatment Technique ◽

X Ray Diffraction ◽

Sem Images ◽

Nucleation Layer ◽

Lateral Overgrowth ◽

N Treatment

AlxGa[Formula: see text]N films were grown on Si/N-treated sapphire substrate by atmospheric pressure metalorganic vapor phase epitaxy (AP-MOVPE) in a home-made vertical reactor. This process can be considered as randomly in situ epitaxial lateral overgrowth (ELO) technology. The growth firstly begins by three-dimensional (3D) mode and is completed in two-dimensional (2D) growth mode as shown by real time in situ laser [Formula: see text][Formula: see text]nm[Formula: see text] reflectometry measurements and confirmed by scanning electron microscopy (SEM) images. Secondary ion mass spectroscopy (SIMS) measurements evidence Al composition pulling effect in the AlxGa[Formula: see text]N layer. The Si/N treatment technique is compared to conventional AlxGa[Formula: see text]N growth techniques. The results of high-resolution X-ray diffraction (HRXRD), photoluminescence (PL) measurements and SEM images agree well on the fact that the Si/N treatment produces AlxGa[Formula: see text]N layers with comparable qualities of AlxGa[Formula: see text]N layers grown on high temperature GaN template but with much higher qualities than AlxGa[Formula: see text]N layers grown on low temperature AlN nucleation layer. Moreover, the Si/N treatment technique permits the growth of high quality AlxGa[Formula: see text]N layers with appreciable thicknesses with respect to the others techniques.

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SOI Interface Structures in Selective Epitaxial Growth

MRS Proceedings ◽

10.1557/proc-238-707 ◽

1991 ◽

Vol 238 ◽

Cited By ~ 2

Author(s):

Zara S. Weng ◽

R. Gronsky ◽

J. C. Lou ◽

W. G. Oldham

Keyword(s):

Epitaxial Growth ◽

Silicon On Insulator ◽

Epitaxial Lateral Overgrowth ◽

Structural Defects ◽

Selective Epitaxial Growth ◽

Lateral Overgrowth ◽

Silicon Growth ◽

Interface Structures ◽

Oxygen Fluorine

ABSTRACTSilicon-on-insulator structures were formed by the selective epitaxial growth (SEG) of silicon and the epitaxial lateral overgrowth (ELO) of oxide shapes using an LPCVD hot-walled reactor at 850°C. The homoepitaxial interface changed character with modifications of the gas composition during the in-situ pre-epitaxial bake at 900°C. HREM images show ellipsoid-shaped inclusions lying along the homoepitaxial interface for silicon growth conducted with no dichlorosilane (DCS) flow during the prebake in H2. SIMS analysis indicates a large oxygen, fluorine, and carbon concentration at the interface. For structures grown with a small DCS flow in addition to H2 during the prebake, the homoepitaxial structural defects and the oxygen, fluorine, and carbon peaks are removed.

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Improvement in Crystalline Quality of InGaN-Based Epilayer on Sapphire via Nanoscaled Epitaxial Lateral Overgrowth

Japanese Journal of Applied Physics ◽

10.1143/jjap.49.105501 ◽

2010 ◽

Vol 49 (10) ◽

pp. 105501 ◽

Cited By ~ 3

Author(s):

Ching-Hsueh Chiu ◽

Da-Wei Lin ◽

Zhen-Yu Li ◽

Chin-Hua Chiu ◽

Chu-Li Chao ◽

...

Keyword(s):

Epitaxial Lateral Overgrowth ◽

Crystalline Quality ◽

Lateral Overgrowth

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Study of ELOG GaN for Application in the Fabrication of Micro-channels for Optoelectronic Devices

MRS Proceedings ◽

10.1557/proc-0892-ff26-08 ◽

2005 ◽

Vol 892 ◽

Author(s):

Lee E Rodak ◽

N J Berry Ann ◽

Kalyan Reddy Kasarla ◽

Nanying Yang ◽

D Korakakis

Keyword(s):

Three Dimensional ◽

Wide Band ◽

Epitaxial Lateral Overgrowth ◽

Wide Band Gap ◽

Lateral Overgrowth ◽

Micro Channels ◽

Lateral Growth Rate ◽

Technical Effort ◽

Novel Devices

AbstractGallium Nitride (GaN) is a promising wide band gap semiconductor material for many optoelectronic applications, especially in the near UV range. Over the past several years, an extensive technical effort has been focused on improving the quality of GaN films through various overgrowth techniques such as epitaxial lateral overgrowth (ELOG), facet controlled epitaxial lateral overgrowth (FACELO), and Pendeoepitaxy. ELOG has been shown to reduce the density of threading dislocations by up to five orders of magnitude [1], however a complete physical model describing lateral overgrowth is needed in order to take full advantage of the process. A lateral overgrowth model will allow for the design and fabrication of three dimensional structures that can lead to novel devices and also to efficient biosensors by integrating micro and nano channels on the same chip as the optoelectronic components.A two-step process has been used to successfully control the geometry of overgrown GaN. Conditions have been identified which give a reduced lateral growth rate, in order to allow expansion of the {112n} plane to form vertical sidewalls and for the design of channel width. These geometries are being examined for possible application in laser diode and micro-channel fabrication for integrating bio-agent detection modules.

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Influence of SiH4 Flow Rate on GaN Films with In Situ SiNx Mask on Sapphire Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.904.29 ◽

2014 ◽

Vol 904 ◽

pp. 29-32

Author(s):

Zhong Hui Li ◽

Da Qing Peng ◽

Wei Ke Luo ◽

Liang Li ◽

Dong Guo Zhong

Keyword(s):

Flow Rate ◽

Sapphire Substrate ◽

Epitaxial Lateral Overgrowth ◽

Growth Time ◽

X Ray Diffraction ◽

Lateral Overgrowth ◽

Transmission Electron ◽

Substrate Properties ◽

Dislocations Density

Sapphire substrate was treated by SiH4under NH3atmosphere before GaN growth and nanosize islands SiNxmask was formed on the substrate. Properties of GaN films were investigated by high resolution X-ray diffraction, photoluminescence and transmission electron microscopy. The results indicated that the SiH4flow rate is an important factor affecting the size and density of SiNxmask besides SiH4treatment time.The GaN films grown on the SiNx-patterned sapphire substrate revealed an epitaxial lateral overgrowth mode, which affected 3D to 2D growth time and the microstructures of GaN films. The lowest FWHM value of (102) rocking curve was 286 arcsec. as the SiH4flow rate of 0.5sccm, with the calcultated edge-type dislocations density of 4.28×109cm-2.

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