Download or read book Epitaxial Growth of GaN with Graded AlGaN on Patterned Silicon 111 Substrates by Metal organic Chemical Vapor Deposition written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solid State Lighting Reliability Part 2 written by Willem Dirk van Driel and published by Springer. This book was released on 2017-07-11 with total page 603 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past four years we have witnessed rapid development in technology and significant market penetration in many applications for LED systems. New processes and new materials have been introduced; new standards and new testing methods have been developed; new driver, control and sensing technologies have been integrated; and new and unknown failure modes have also been presented. In this book, Solid State Lighting Reliability Part 2, we invited the experts from industry and academia to present the latest developments and findings in the LED system reliability arena. Topics in this book cover the early failures and critical steps in LED manufacturing; advances in reliability testing and standards; quality of colour and colour stability; degradation of optical materials and the associated chromaticity maintenance; characterization of thermal interfaces; LED solder joint testing and prediction; common failure modes in LED drivers; root causes for lumen depreciation; corrosion sensitivity of LED packages; reliability management for automotive LEDs, and lightning effects on LEDs. This book is a continuation of Solid State Lighting Reliability: Components to Systems (published in 2013), which covers reliability aspects ranging from the LED to the total luminaire or system of luminaires. Together, these two books are a full set of reference books for Solid State Lighting reliability from the performance of the (sub-) components to the total system, regardless its complexity.
Download or read book Epitaxial Growth of GaN on Si Substrate by Low Pressure Metal Organic Chemical Vapor Deposition written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth of GaN and AlGaN Thin Films Using Conventional and Pendeo epitaxial Growth Processes on 6H silicon Carbide 0001 and Silicon 111 Substrates written by Thomas Gehrke and published by . This book was released on 2000 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal organic Chemical Vapor Epitaxy of GaN on Si 111 for Optoelectronic Applications written by Alain E. Kaloyeros and published by . This book was released on 1998 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface preparation, seed and buffer layer growth, and annealing conditions. Films were extensively characterized via X-ray diffraction, Rutherford backscatter, atomic force microscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy. Optimized growth rates of 60-120 A/min were achieved at 0.8 torr pressure, with 1:1 gallium to nitride ratio to within 0.1%. Films were hexagonal and polycrystalline with 3 nitride bi-layer buffers, with annealing, allowed stoichiometric gallium nitride growth of up to 6000 A, but the temperatures used were not high enough to deposit epitaxial gallium nitride.
Download or read book Metal Organic Chemical Vapor Epitaxy of GaN on Si 111 for Optoelectronic Applications written by Alain E. Kaloyeros and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface preparation, seed and buffer layer growth, and annealing conditions. Films were extensively characterized via X-ray diffraction, Rutherford backscatter, atomic force microscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy. Optimized growth rates of 60-120 A/min were achieved at 0.8 torr pressure, with 1:1 gallium to nitride ratio to within 0.1%. Films were hexagonal and polycrystalline with 3 nitride bi-layer buffers, with annealing, allowed stoichiometric gallium nitride growth of up to 6000 A, but the temperatures used were not high enough to deposit epitaxial gallium nitride.
Download or read book Hot wall Low Pressure Chemical Vapor Deposition Growth and Characterization of GaN and Epitaxial AlN on Si 111 written by Karen Heinselman and published by . This book was released on 2016 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physical and electronic properties of aluminum nitride (AlN) have made it attractive for a wide variety of applications, including bulk and surface acoustic wave (B/SAW) resonators and thin film dielectric coatings. Due to its wide band gap of 6.2 eV, AlN is a good insulator. The chemical durability of AlN makes it appealing for extreme environmental conditions. Its thermal expansion coefficient is similar to those of other semiconductor materials such as Si and SiC, making it appropriate for use in high temperature applications as well. In this work, we demonstrate the growth of AlN and GaN thin films using hotwall low pressure chemical vapor deposition (LPCVD) in order to obtain epitaxial AlN growth with a parallelizable, inexpensive method (relative to the current epitaxial growth method, molecular beam epitaxy). This dissertation demonstrates the growth of aluminum nitride thin films (between 70 nm and 1 [MICRO SIGN]m in thickness) on Si (111) substrates using hot-wall low pressure chemical vapor deposition (LPCVD) at 1000 ? C and 2 torr. Prior to growth, the substrates were pretreated in situ with dichlorosilane cleaning step, the parameters of which were varied to optimize the c-axis alignment of the grown thin film AlN. In addition, nucleation time for the aluminum precursor, trimethylaluminum (TMAl) was varied and optimized. X-ray diffraction (XRD) was performed on the samples for characterization. With the optimal nucleation time and dichlorosilane pretreatment, the 2[theta]-[omega] FWHM of the resulting AlN film was 1160 arcsec, and the FWHM of the [omega] rocking curve was 1.6? . These optimal parameters exhibited epitaxial AlN peaks aligned with the Si (111) substrate when characterized using a tilted phi scan XRD technique. Transmission electron microscopy (TEM) provides a second epitaxial alignment confirmation. Backside etching of the Si (111) substrate to create freestanding AlN thin film drums is demonstrated. This access to the back side of the AlN thin films allows the fabrication of future bulk acoustic wave (BAW) resonator devices and testing the piezoelectric response of these materials. For alternate applications, GaN was grown on AlN buffer layers on Si (111) substrates using hot-wall LPCVD. The resulting film was c-axis aligned, with an XRD FWHM of 1420 arcsec for the GaN (001) 2[theta]-[omega] peak, and the FWHM of the rocking curve was 3.8? . Capacitance-voltage data on the grown GaN on AlN indicate n-type films with residual electron concentrations of roughly 1017 cm[-]3 .
Download or read book Molecular Beam Epitaxial Growth of Gan on Si 111 Substrate written by Zhongjie Xu and published by . This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure and Strain Properties of GaN Films Grown on Si 111 Substrates with AlxGa1 xN AlyGa1 yN Superlattices Supported by the National Natural Science Foundation of China Under Grant Nos 61076120 and 61106130 and the Natural Science Foundation and Scientific Support Plan of Jiangsu Province Under Grant Nos BK2012516 BK20131072 and BE2012007 written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : GaN films with an Alx Ga1−x N/Aly Ga1−y N superlattice (SL) buffer layer are grown on Si(111) substrates by metal-organic chemical vapor deposition (MOCVD). The structure and strain properties of the samples are studied by optical microscopy, Raman spectroscopy, x-ray diffractometry and atomic force microscopy. The results show that the strain status and crystalline quality of the GaN layers are strongly dependent on the difference of the Al composition between Alx Ga1−x N barriers and Aly Ga1−y N wells in the SLs. With a large Al composition difference, the GaN film tends to generate cracks on the surface due to the severe relaxation of the SLs. Otherwise, when using a small Al composition difference, the crystalline quality of the GaN layer degrades due to the poor function of the SLs in filtering dislocations. Under an optimized condition that the Al composition difference equals 0.1, the crack-free and compressive strained GaN film with an improved crystalline quality is achieved. Therefore, the Alx Ga1−x N/Aly Ga1−y N SL buffer layer is a promising buffer structure for growing thick GaN films on Si substrates without crack generation.
Download or read book Molecular Beam Epitaxial Growth of GaN on Si 111 Substrate written by Zhongjie Xu (M. Phil.) and published by . This book was released on 2010 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth of Gallium Nitride on Porous Templates by Metalorganic Chemical Vapor Deposition written by Yi Fu and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Epitaxial Growth of High Quality GaN on Appropriately Nitridated Si Substrate by Metal Organic Vapor Phase Deposition written by 溫武義 and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Epitaxial Growth of High Quality GaN on Appropriately Nitridated Si Substrate by Metal Organic Vapor Phase Deposition written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book GaN AIN InN and Related Materials Volume 892 written by Martin Kuball and published by . This book was released on 2006-03-27 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.
Download or read book Lateral Epitaxial Overgrowth of GaN on Si 111 written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The lateral epitaxial overgrowth of GaN on Si(111) substrates was achieved using an extension of our standard LEO process on GaN/Al2O3 substrates, and the reduction of the dislocation density was demonstrated by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The growth on the Si(111) substrate was initiated with the deposition of a thin AlN buffer layer to avoid the formation of potentially detrimental silicon nitride at the interface. The wafers were then patterned with a SiO2 layer in which 5 micron wide opening separated by 35 microns were etched using buffered HF. After reloading the samples in the MOCVD chamber, the LEO growth was performed using our standard parameters. There are a few unresolved issues concerning the effect of the AlN buffer thickness and its chemical compatibility with the SiO2 mask layer, but after a basic optimization we were able to obtain 5 microns of lateral overgrowth with smooth sidewalls in a reproducible manner. We are currently investigating the use of mask materials other than SiO2 to achieve LEO on Si(111) over a wider range of process parameters.
Download or read book Effect of Fluid Dynamics and Reactor Design on the Epitaxial Growth of Gallium Nitride on Silicon Substrate by Metalorganic Chemical Vapor Deposition written by Yungeng Gao and published by . This book was released on 2000 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in GaN GaAs SiC and Related Alloys on Silicon Substrates Volume 1068 written by Materials Research Society. Meeting Symposium C. and published by . This book was released on 2008-08-29 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.
