Effects of the group V/III ratio and a gan inter-layer on the crystal quality of InN grown by using the hydride vapor-phase epitaxy method

ABSTRACTThe effects of flowrate variation and geometry on the growth rate, growth uniformity and crystal quality were investigated in a horizontal Gallium Nitride vapor phase epitaxy reactor. To better understand the effects of these parameters, numerical model predictions are compared to experimentally observed values. Parasitic gas phase reactions between group III and group V sources and deposition of material on the wall are shown to lead to reduced overall growth rates and may be responsible for inferior crystal quality. A low ammonia concentration is correlated with the deposition of polycrystalline films. A low V/III ratio and an ammonia concentration lead to poor crystalline quality and increased yellow luminescence. An optimum HVPE growth process requires selection of reactor geometry and operating conditions to minimize these parasitic reactions and wall deposition while providing a uniform reactant distribution across the substrate.

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Optimization of Reactor Geometry and Growth Conditions for GaN Halide Vapor Phase Epitaxy

MRS Proceedings ◽

10.1557/proc-423-227 ◽

1996 ◽

Vol 423 ◽

Cited By ~ 5

Author(s):

S. A. Safvi ◽

N. R. Perkins ◽

M. N. Horton ◽

A. Thon ◽

D. Zhi ◽

...

Keyword(s):

Numerical Model ◽

Vapor Phase ◽

Growth Rates ◽

Ammonia Concentration ◽

Growth Conditions ◽

Vapor Phase Epitaxy ◽

Operating Conditions ◽

Crystal Quality ◽

Group V ◽

Reactor Geometry

AbstractA numerical model of an experimental gallium nitride horizontal vapor phase epitaxy reactor is presented. The model predicts the flow, concentration profiles, and growth rates. The effects of flowrate variation and geometry on the growth rate, growth uniformity and crystal quality were investigated. Numerical model predictions are compared to experimentally observed values. Parasitic gas phase reactions between group III and group V sources and deposition of material on the wall are shown to lead to reduced overall growth rates and inferior crystal quality. A low ammonia concentration is correlated to deposition of polycrystalline films. An optimum HVPE growth process requires selection of reactor geometry and operating conditions to minimize parasitic reactions and wall deposition while providing a uniform reactant distribution across the substrate.

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Flux-mediated epitaxy: general application in vapor phase epitaxy to single crystal quality of complex oxide films

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2004.10.091 ◽

2005 ◽

Vol 275 (1-2) ◽

pp. 325-330 ◽

Cited By ~ 16

Author(s):

Y. Matsumoto ◽

R. Takahashi ◽

H. Koinuma

Keyword(s):

Single Crystal ◽

Vapor Phase ◽

Oxide Films ◽

Complex Oxide ◽

Vapor Phase Epitaxy ◽

Crystal Quality ◽

General Application ◽

Complex Oxide Films

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Study of the structural quality of GaN epitaxial layers obtained by hydride vapor phase epitaxy using a low-temperature buffer layer

Crystallography Reports ◽

10.1134/s1063774515060036 ◽

2015 ◽

Vol 60 (6) ◽

pp. 889-894

Author(s):

I. A. Belogorohov ◽

A. A. Donskov ◽

S. N. Knyazev ◽

Yu. P. Kozlova ◽

V. F. Pavlov ◽

...

Keyword(s):

Low Temperature ◽

Buffer Layer ◽

Vapor Phase ◽

Vapor Phase Epitaxy ◽

Hydride Vapor Phase Epitaxy ◽

Structural Quality ◽

Epitaxial Layers

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Effects of Growth Temperatures on Crystal Quality of GaN by Vapor Phase Epitaxy Using GaCl3and NH3

Japanese Journal of Applied Physics ◽

10.7567/jjap.50.085501 ◽

2011 ◽

Vol 50 (8R) ◽

pp. 085501

Author(s):

Tetsuzo Ueda ◽

Masaaki Yuri ◽

James S. Harris, Jr.

Keyword(s):

Vapor Phase ◽

Vapor Phase Epitaxy ◽

Crystal Quality

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The influence of sapphire substrate orientation on crystalline quality of GaN films grown by hydride vapor phase epitaxy

Physica B Condensed Matter ◽

10.1016/j.physb.2009.08.211 ◽

2009 ◽

Vol 404 (23-24) ◽

pp. 4919-4921

Author(s):

Anatolij Govorkov ◽

Alexsandr Donskov ◽

Lev Diakonov ◽

Yulia Kozlova ◽

Sergej Malahov ◽

...

Keyword(s):

Vapor Phase ◽

Sapphire Substrate ◽

Vapor Phase Epitaxy ◽

Hydride Vapor Phase Epitaxy ◽

Crystalline Quality ◽

Substrate Orientation

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Growth of Freestanding Gallium Nitride (GaN) Through Polyporous Interlayer Formed Directly During Successive Hydride Vapor Phase Epitaxy (HVPE) Process

Crystals ◽

10.3390/cryst10020141 ◽

2020 ◽

Vol 10 (2) ◽

pp. 141 ◽

Cited By ~ 2

Author(s):

Haixiao Hu ◽

Baoguo Zhang ◽

Lei Liu ◽

Deqin Xu ◽

Yongliang Shao ◽

...

Keyword(s):

Gallium Nitride ◽

Vapor Phase ◽

Chemical Vapor ◽

Growth Stress ◽

Vapor Phase Epitaxy ◽

Hydride Vapor Phase Epitaxy ◽

Organic Chemical ◽

High Quality ◽

Continuous Growth

The progress of nitride technology is widely limited and hindered by the lack of high-quality gallium nitride (GaN) wafers. Therefore, a large number of GaN epitaxial devices are grown on heterogeneous substrates. Although various additional treatments of substrate have been used to promote crystal quality, there is still plenty of room for its improvement, in terms of direct and continuous growth based on the hydride vapor phase epitaxy (HVPE) technique. Here, we report a three-step process that can be used to enhance the quality of GaN crystal by tuning V/III rate during successive HVPE process. In the growth, a metal-organic chemical vapor deposition (MOCVD) grown GaN on sapphire (MOCVD-GaN/Al2O3) was employed as substrate, and a high-quality GaN polyporous interlayer, with successful acquisition, without any additional substrate treatment, caused the growth stress to decrease to 0.06 GPa. Meanwhile the quality of GaN improved, and the freestanding GaN was directly obtained during the growth process.

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In-Situ Preparation of GaN Sacrificial Layers on Sapphire Substrate in MOVPE Reactor for Self-Separation of the Overgrown GaN Crystal

Crystals ◽

10.3390/cryst10121100 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1100

Author(s):

Sepideh Faraji ◽

Elke Meissner ◽

Roland Weingärtner ◽

Sven Besendörfer ◽

Jochen Friedrich

Keyword(s):

Vapor Phase ◽

Sapphire Substrate ◽

Vapor Phase Epitaxy ◽

The Self ◽

Etching Process ◽

Hydride Vapor Phase Epitaxy ◽

Etching Parameters ◽

Gan Crystal

GaN layers on sapphire substrates were prepared by using metal organic vapor phase epitaxy (MOVPE) combined with an in-situ H2 etching process for the purpose of later self-separation of thick GaN crystals produced by hydride vapor phase epitaxy (HVPE) on such substrates. The etching process results in deep pits and long voids that formed on the surface and along the lower interface between GaN and sapphire, respectively. The pits, which were investigated by SEM analysis, can be modified in their aspect ratio and density by controlling the etching parameters. Using a proper set of in-situ etching parameters, a seed layer with internal voids can be prepared, which is suitable for HVPE overgrowth and the self-separation process. The quality of the in-situ-etched seed GaN layer and overgrown GaN crystal were characterized by X-ray diffraction (XRD) and defect selective etching (DSE). With the aid of atomic force microscopy (AFM) in tapping mode, the interface morphology of the separated GaN crystal was analyzed. The crystal quality of the separated HVPE-GaN crystal is comparable to the crystal grown on untreated GaN MOVPE-seed, which did not separate from the sapphire substrate. The introduced technique to promote the crystal separation during the HVPE process has no obvious drawback on the quality of the grown GaN crystals. Using this technique, the self-separation occurs more gently due to a weakened interface between GaN/sapphire. The conventional separation from an untreated seed by pure thermomechanical action results in higher mechanical forces on the crystal and consequently much higher risk of crystal breakage.

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