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Passivation Mechanisms in Locally Etched P-Type Poly-Si on Silicon Nitride/Silicon Oxide Stack
Tunneling oxide passivated contacts are quickly becoming the industry standard for high-efficiency c-Si based photovoltaic cells. Further development of these structures is essential to enable higher efficiencies and better reliability of cells. By utilizing poly-Si/SixNy/SiOx stacks, very high efficiencies have been demonstrated on small area cells. In this work we investigate the cause of the excellent passivation seen by these structures and show that the primary reason of the excellent passivation seen is the blocking B diffusion to the SiOx/c -Si interface. We also show that the interface between the silicon nitride and polysilicon affects B diffusion through to the c-Si interface. Finally, we demonstrate that the composition of the nitride used is of great importance, and that an incorrect nitride composition leads to B diffusion, and is directly correlated to poor passivation performance.
Demonstration of >6.0-kV Breakdown Voltage in Large Area Vertical GaN p-n Diodes With Step-Etched Junction Termination Extensions
Vertical gallium nitride (GaN) p-n diodes have garnered significant interest for use in power electronics where high-voltage blocking and high-power efficiency are of concern. In this article, we detail the growth and fabrication methods used to develop a large area (1 mm 2 ) vertical GaN p-n diode capable of a 6.0-kV breakdown. We also demonstrate a large area diode with a forward pulsed current of 3.5 A, an 8.3-mΩ$\cdot$cm 2 differential specific ON-resistance, and a 5.3-kV reverse breakdown. In addition, we report on a smaller area diode (0.063 mm 2 ) that is capable of 6.4-kV breakdown with a differential specific ON-resistance of 10.2 mΩ$\cdot$cm 2 , when accounting for current spreading through the drift region at a 45° angle. Finally, the demonstration of avalanche breakdown is shown for a 0.063-mm 2 diode with a room temperature breakdown of 5.6 kV. In this work, these results were achieved via epitaxial growth of a 50-μm drift region with a very low carrier concentration of <1×10 15 cm –3 and a carefully designed four-zone junction termination extension.
Etched and Regrown Vertical GaN Junction Barrier Schottky Diodes.
Abstract not provided.
Atomic layer etching of 3D structures in silicon: Self-limiting and nonideal reactions
Not provided.
Transient behavior in quasi-atomic layer etching of silicon dioxide and silicon nitride in fluorocarbon plasmas
Not provided.
Plasma etching of high aspect ratio features in SiO 2 using Ar/C 4 F 8 /O 2 mixtures: A computational investigation
Not provided.
Concentric Hexagonal GaN Structures for Nanophotonics, Fabricated by Selective Vapor-Phase Epitaxy with Ion-Beam Etching
In the Si{sub 3}N{sub 4} layer, coaxial and single submicrometer GaN structures of hexagonal shape with pyramidal facets are formed by selective vapor-phase epitaxy in windows produced with a focused ion beam. It is found that coaxial hexagonal structures are formed during the growth process in ring-shaped mask windows.
Tunable hard x-ray nanofocusing with Fresnel zone plates fabricated using deep etching
Not Available
Deep-level Optical Spectroscopy in Wet-Treated Etched-and-Regrown Nonpolar m-plane GaN Vertical Schottky Diodes.
Abstract not provided.
Exploring Al(X)Ga(1-X)N Nanostructures Fabricated via Top-Down Chemical Wet Etching.
Abstract not provided.
Fabrication and field emission properties of vertical, tapered GaN nanowires etched via phosphoric acid.
Abstract not provided.
Exploring Al(X)Ga(1-X)N Nanostructures Fabricated via Chemical Wet Etching.
Abstract not provided.
Etched and Regrown Vertical GaN Junction Barrier Schottky Diodes.
Abstract not provided.