다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Wide bandgap semiconductors show superior material properties enabling potential power device operation at higher temperatures, voltages, and switching speeds than current Si technology. As a result, a new generation of power devices is being developed for power converter applications in which traditional Si power devices show limited operation. The use of these new power semiconductor devices will allow both an important improvement in the performance of existing power converters and the development of new power converters, accounting for an increase in the efficiency of the electric energy transformations and a more rational use of the electric energy. At present, SiC and GaN are the more promising semiconductor materials for these new power devices as a consequence of their outstanding properties, commercial availability of starting material, and maturity of their technological processes. This paper presents a review of recent progresses in the development of SiC- and GaN-based power semiconductor devices together with an overall view of the state of the art of this new device generation.

A Survey of Wide Bandgap Power Semiconductor Devices

Light-Emitting Diodes. (Monographs in Electrical and Electronic Engineering.) By A. A. Bergh and P. J. Dean. Pp. viii+591. (Clarendon: Oxford; Oxford University: London, 1976.) £22.

/pdf/light-emitting-diodes-ubzde6g9qc.pdf

Light-emitting diodes

An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

The unique characteristics of SiC make it attractive for a variety of applications that are not well served by existing silicon technology. One such application is high-power, moderate-frequency microwave amplifiers and power sources based on devices such as MESFETs (metal-semiconductor field-effect transistors), static induction transistors (SITs), and IMPATT (impact ionization avalanche transit-time) diodes. Another important application involves high-temperature integrated circuits for sensing and control, where SiC bipolar and JFET (junction field-effect transistor) integrated circuits are the preferred implementations. A major emerging opportunity for SiC lies in the area of sensors for hostile environments. Developments to date include MEMS (micro-electro-mechanical sensor) devices for motion sensors, gas sensors for combustion control, and solar-blind UV optical detectors. In each area we describe the application requirements, highlight the advantages of SiC, and report the current status of SiC technology.

Specialized Silicon Carbide Devices and Applications

Design and Fabrication of SiC RESURF MOSFETs

An alternative source supply sequence was applied to aluminum nitride (AlN) growth by rf-plasma-assisted molecular-beam epitaxy on silicon carbide (SiC) substrates with a high-quality AlN template layer. Under a nitrogen-only source supply after aluminum source supply, multi-cycle oscillations of reflection high-energy electron diffraction (RHEED) intensity were observed, which were due to layer-by-layer growth of the AlN layer. The RHEED oscillation under nitrogen-only supply indicates that excess aluminum exists on the surface as a few-monolayer-thick wetting layer along with microdroplets. By repeating the sequence, a 105 nm thick high-quality AlN layer was coherently grown on a SiC substrate without aluminum droplets.

https://iopscience.iop.org/article/10.7567/1882-0786/ab6588/pdf

Multi-cycle RHEED oscillation under nitrogen supply in alternative source supply AlN growth by rf-MBE

We investigated the influence of vacuum annealing on the interface properties of silicon carbide (SiC) metal–oxide–semiconductor (MOS) structures. For as-oxidized and nitric oxide (NO)-annealed samples, the interface state density (D it) near the conduction band edge (E C) of SiC did not increase by subsequent vacuum annealing. For phosphoryl chloride (POCl3)-annealed samples, in contrast, D it at E C − 0.2 eV increased from 1.3 × 1010 to 2.2 × 1012 cm−2 eV−1 by vacuum annealing, and the channel mobility of MOS field effect transistors (MOSFETs) decreased from 109 to 44 cm2 V−1 s−1. The mechanism of the observed increase in D it was discussed based on the results of the secondary ion mass spectrometry measurement.

https://iopscience.iop.org/article/10.7567/1347-4065/ab2557/pdf

Influence of vacuum annealing on interface properties of SiC (0001) MOS structures

The present invention provides a junction field effect transistor (JFET) which can achieve a switching operation with high voltage durability and high current. The JFET comprises: a gate area (2) of second conductive type, a source area (1) of first conductive type, and a channel area (10) of first conductive type connected with the source area and a limiting area (5) of second conductive type connected with the gate area and limiting the channel area that are all configured on the surface of semiconductor substrate; a drain area (3) of first conductive type configured on the back; and, a drift area (4) of first conductive type continued in the depth direction of the substrate from the channel to the drain. The density of the dopant of the first type in the drift area and the channel area is lower than the density of the dopant of the first type in the source area and the drain area and also the density of the dopant of second conductive type in the limiting area.

Tsunenobu Kimoto

Papers

Specialized Silicon Carbide Devices and Applications

Design and Fabrication of SiC RESURF MOSFETs

Multi-cycle RHEED oscillation under nitrogen supply in alternative source supply AlN growth by rf-MBE

Influence of vacuum annealing on interface properties of SiC (0001) MOS structures

Junction field effect transistor and the manufacturing method thereof