Author: Yi Fu
Publisher:
ISBN:
Category : Gallium nitride
Languages : en
Pages :
Book Description
In this dissertation, GaN growth on porous templates by metalorganic chemical vapor deposition (MOCVD) was studied. The motivation of this research is pursuing an effective reduction of defects in GaN by its submicron-scale and nano-scale epitaxial lateral overgrowth (ELO) on these porous templates, which included porous TiN/GaN (P-TiN), imprint lithography patterned Ti/GaN (IL-Ti), carbon-face nano-porous SiC (C-PSC), and silicon-face nano-porous SiC (Si-PSC). The porous TiN/GaN was formed in situ in MOCVD reactor by annealing a Ti-covered GaN seed layer. This simplicity makes the GaN ELO on the P-TiN more cost-efficient than the conventional ELO which requires ex situ photolithography and/or etching. Both the GaN nano-ELO and the GaN micron-ELO could be realized on P-TiN by controlling the GaN nucleation scheme. The reduction efficacy of edge threading dislocation (TD) was ~15 times. The optical characterization indicated that the non-radiative point-defects in GaN grown were reduced significantly on the P-TiN. The imprint lithography patterned Ti/GaN had uniformly distributed submicron Ti pads on GaN seed layer. These Ti pads acted as GaN ELO masks. The TD reduction efficacy of the IL-Ti was only ~2 due to the low coverage of Ti (~25%) on the GaN seed layer and the low pressure (30 Torr) employed during GaN ELO. Even with a small reduction of TDs, the point-defects in GaN were effectively lowered by the IL-Ti. Hydrogen polishing, sacrificial oxidation, and chemical mechanical polishing were employed to remove surface damage on the PSC substrates. Nitrogen-polarity GaN grown on the C-PSC was highly dislocated because the rough surface of C-PSC induced strong misorientation between GaN nucleation islands. The efficacy of Si-PSC on defect reduction primarily depended on the GaN nucleation schemes. A high density of GaN nano-nucleation-islands was required to realize the GaN nano-ELO extensively. With such a nucleation scheme, the GaN grown on Si-PSC had a ~20 times reduction on the density of the mixed and screw TDs compared with control sample. This growth method is promising for effective defect reduction within a small GaN thickness. Reducing the GaN nucleation density further lowered the TD density but also diminished the efficacy of Si-PSC. These results were explained by a growth model based on the mosaic structure of GaN.
Growth of Gallium Nitride on Porous Templates by Metalorganic Chemical Vapor Deposition
Author: Yi Fu
Publisher:
ISBN:
Category : Gallium nitride
Languages : en
Pages :
Book Description
In this dissertation, GaN growth on porous templates by metalorganic chemical vapor deposition (MOCVD) was studied. The motivation of this research is pursuing an effective reduction of defects in GaN by its submicron-scale and nano-scale epitaxial lateral overgrowth (ELO) on these porous templates, which included porous TiN/GaN (P-TiN), imprint lithography patterned Ti/GaN (IL-Ti), carbon-face nano-porous SiC (C-PSC), and silicon-face nano-porous SiC (Si-PSC). The porous TiN/GaN was formed in situ in MOCVD reactor by annealing a Ti-covered GaN seed layer. This simplicity makes the GaN ELO on the P-TiN more cost-efficient than the conventional ELO which requires ex situ photolithography and/or etching. Both the GaN nano-ELO and the GaN micron-ELO could be realized on P-TiN by controlling the GaN nucleation scheme. The reduction efficacy of edge threading dislocation (TD) was ~15 times. The optical characterization indicated that the non-radiative point-defects in GaN grown were reduced significantly on the P-TiN. The imprint lithography patterned Ti/GaN had uniformly distributed submicron Ti pads on GaN seed layer. These Ti pads acted as GaN ELO masks. The TD reduction efficacy of the IL-Ti was only ~2 due to the low coverage of Ti (~25%) on the GaN seed layer and the low pressure (30 Torr) employed during GaN ELO. Even with a small reduction of TDs, the point-defects in GaN were effectively lowered by the IL-Ti. Hydrogen polishing, sacrificial oxidation, and chemical mechanical polishing were employed to remove surface damage on the PSC substrates. Nitrogen-polarity GaN grown on the C-PSC was highly dislocated because the rough surface of C-PSC induced strong misorientation between GaN nucleation islands. The efficacy of Si-PSC on defect reduction primarily depended on the GaN nucleation schemes. A high density of GaN nano-nucleation-islands was required to realize the GaN nano-ELO extensively. With such a nucleation scheme, the GaN grown on Si-PSC had a ~20 times reduction on the density of the mixed and screw TDs compared with control sample. This growth method is promising for effective defect reduction within a small GaN thickness. Reducing the GaN nucleation density further lowered the TD density but also diminished the efficacy of Si-PSC. These results were explained by a growth model based on the mosaic structure of GaN.
Publisher:
ISBN:
Category : Gallium nitride
Languages : en
Pages :
Book Description
In this dissertation, GaN growth on porous templates by metalorganic chemical vapor deposition (MOCVD) was studied. The motivation of this research is pursuing an effective reduction of defects in GaN by its submicron-scale and nano-scale epitaxial lateral overgrowth (ELO) on these porous templates, which included porous TiN/GaN (P-TiN), imprint lithography patterned Ti/GaN (IL-Ti), carbon-face nano-porous SiC (C-PSC), and silicon-face nano-porous SiC (Si-PSC). The porous TiN/GaN was formed in situ in MOCVD reactor by annealing a Ti-covered GaN seed layer. This simplicity makes the GaN ELO on the P-TiN more cost-efficient than the conventional ELO which requires ex situ photolithography and/or etching. Both the GaN nano-ELO and the GaN micron-ELO could be realized on P-TiN by controlling the GaN nucleation scheme. The reduction efficacy of edge threading dislocation (TD) was ~15 times. The optical characterization indicated that the non-radiative point-defects in GaN grown were reduced significantly on the P-TiN. The imprint lithography patterned Ti/GaN had uniformly distributed submicron Ti pads on GaN seed layer. These Ti pads acted as GaN ELO masks. The TD reduction efficacy of the IL-Ti was only ~2 due to the low coverage of Ti (~25%) on the GaN seed layer and the low pressure (30 Torr) employed during GaN ELO. Even with a small reduction of TDs, the point-defects in GaN were effectively lowered by the IL-Ti. Hydrogen polishing, sacrificial oxidation, and chemical mechanical polishing were employed to remove surface damage on the PSC substrates. Nitrogen-polarity GaN grown on the C-PSC was highly dislocated because the rough surface of C-PSC induced strong misorientation between GaN nucleation islands. The efficacy of Si-PSC on defect reduction primarily depended on the GaN nucleation schemes. A high density of GaN nano-nucleation-islands was required to realize the GaN nano-ELO extensively. With such a nucleation scheme, the GaN grown on Si-PSC had a ~20 times reduction on the density of the mixed and screw TDs compared with control sample. This growth method is promising for effective defect reduction within a small GaN thickness. Reducing the GaN nucleation density further lowered the TD density but also diminished the efficacy of Si-PSC. These results were explained by a growth model based on the mosaic structure of GaN.
Growth of Gallium Nitride and Indium Gallium Nitride Nano/Microstructures Via Metal Organic Chemical Vapor Deposition
Author: David Wood
Publisher:
ISBN:
Category :
Languages : en
Pages : 166
Book Description
Indium gallium nitride nanostructures were grown at a temperature of 600oC and a total V/III ratio of 10,000. Below an indium fraction of 0.20 nanostructures were observed with diameters between 200 and 350 nanometers. The diameters were found to decrease with increasing indium fraction. Texturing in the (0001) c-plane direction was also enhanced as the indium fraction was increased. At indium fractions above 0.20 the formation of metal droplets within a porous indium gallium nitride film were observed. There are several untried deposition recipes that can yet be attempted to grow the nanostructures over the entire compositional range of the indium gallium nitride alloy.
Publisher:
ISBN:
Category :
Languages : en
Pages : 166
Book Description
Indium gallium nitride nanostructures were grown at a temperature of 600oC and a total V/III ratio of 10,000. Below an indium fraction of 0.20 nanostructures were observed with diameters between 200 and 350 nanometers. The diameters were found to decrease with increasing indium fraction. Texturing in the (0001) c-plane direction was also enhanced as the indium fraction was increased. At indium fractions above 0.20 the formation of metal droplets within a porous indium gallium nitride film were observed. There are several untried deposition recipes that can yet be attempted to grow the nanostructures over the entire compositional range of the indium gallium nitride alloy.
Porous Silicon Carbide and Gallium Nitride
Author: Randall M. Feenstra
Publisher: John Wiley & Sons
ISBN: 9780470751824
Category : Technology & Engineering
Languages : en
Pages : 332
Book Description
Porous Silicon Carbide and Gallium Nitride: Epitaxy, Catalysis, and Biotechnology Applications presents the state-of-the-art in knowledge and applications of porous semiconductor materials having a wide band gap. This comprehensive reference begins with an overview of porous wide-band-gap technology, and describes the underlying scientific basis for each application area. Additional chapters cover preparation, characterization, and topography; processing porous SiC; medical applications; magnetic ion behavior, and many more
Publisher: John Wiley & Sons
ISBN: 9780470751824
Category : Technology & Engineering
Languages : en
Pages : 332
Book Description
Porous Silicon Carbide and Gallium Nitride: Epitaxy, Catalysis, and Biotechnology Applications presents the state-of-the-art in knowledge and applications of porous semiconductor materials having a wide band gap. This comprehensive reference begins with an overview of porous wide-band-gap technology, and describes the underlying scientific basis for each application area. Additional chapters cover preparation, characterization, and topography; processing porous SiC; medical applications; magnetic ion behavior, and many more
Growth and Characterization of Gallium Nitride and Boron Gallium Nitride by Metalorganic Chemical Vapor Deposition
Author: Chih-Hsun Wei
Publisher:
ISBN: 9780599613294
Category :
Languages : en
Pages : 131
Book Description
Publisher:
ISBN: 9780599613294
Category :
Languages : en
Pages : 131
Book Description
Gallium Nitride Materials and Devices
Author: Cole W. Litton
Publisher: SPIE-International Society for Optical Engineering
ISBN: 9780819461636
Category : Science
Languages : en
Pages : 322
Book Description
Proceedings of SPIE present the original research papers presented at SPIE conferences and other high-quality conferences in the broad-ranging fields of optics and photonics. These books provide prompt access to the latest innovations in research and technology in their respective fields. Proceedings of SPIE are among the most cited references in patent literature.
Publisher: SPIE-International Society for Optical Engineering
ISBN: 9780819461636
Category : Science
Languages : en
Pages : 322
Book Description
Proceedings of SPIE present the original research papers presented at SPIE conferences and other high-quality conferences in the broad-ranging fields of optics and photonics. These books provide prompt access to the latest innovations in research and technology in their respective fields. Proceedings of SPIE are among the most cited references in patent literature.
The growth and characterization of gallium nitride epitaxial layers grown by low pressure metalorganic chemical vapor deposition
Author: Adrian Lawrence Holmes
Publisher:
ISBN:
Category :
Languages : en
Pages : 90
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 90
Book Description
Metalorganic Chemical Vapor Deposition of Gallium Nitride on Sacrificial Substrates
Author: William Edward Fenwick
Publisher:
ISBN:
Category : Gallium compounds
Languages : en
Pages :
Book Description
ZnO, because of its similar lattice constant and thermal expansion coefficient, is a promising substrate for growth of low defect-density GaN. The major hurdles for GaN growth on ZnO are the instability of ZnO in a hydrogen atmosphere and out-diffusion of zinc and oxygen from the substrate. A process was developed for the MOCVD growth of wurtzite GaN and InxGa1-xN on ZnO, and the structural and optical properties of these films were studied. High zinc and oxygen concentrations remained an issue, however, and the diffusion of zinc and oxygen into the subsequent GaN layer was studied more closely.
Publisher:
ISBN:
Category : Gallium compounds
Languages : en
Pages :
Book Description
ZnO, because of its similar lattice constant and thermal expansion coefficient, is a promising substrate for growth of low defect-density GaN. The major hurdles for GaN growth on ZnO are the instability of ZnO in a hydrogen atmosphere and out-diffusion of zinc and oxygen from the substrate. A process was developed for the MOCVD growth of wurtzite GaN and InxGa1-xN on ZnO, and the structural and optical properties of these films were studied. High zinc and oxygen concentrations remained an issue, however, and the diffusion of zinc and oxygen into the subsequent GaN layer was studied more closely.
Homo- and Hetero-epitaxial Growth of Gallium Nitride by Metalorganic Chemical Vapour Deposition
Author: Andreas Rudolf Antonius Zauner
Publisher:
ISBN: 9789037305562
Category :
Languages : en
Pages : 131
Book Description
Publisher:
ISBN: 9789037305562
Category :
Languages : en
Pages : 131
Book Description
Studies of Gallium Nitride Grown on Silicon Substrate by Metalorganic Chemical Vapor Deposition
Author: Jingli Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 218
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 218
Book Description
Technology of Gallium Nitride Crystal Growth
Author: Dirk Ehrentraut
Publisher: Springer Science & Business Media
ISBN: 3642048307
Category : Science
Languages : en
Pages : 337
Book Description
This book discusses the important technological aspects of the growth of GaN single crystals by HVPE, MOCVD, ammonothermal and flux methods for the purpose of free-standing GaN wafer production.
Publisher: Springer Science & Business Media
ISBN: 3642048307
Category : Science
Languages : en
Pages : 337
Book Description
This book discusses the important technological aspects of the growth of GaN single crystals by HVPE, MOCVD, ammonothermal and flux methods for the purpose of free-standing GaN wafer production.