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 effects of postimplantation annealing on the homogeneous depth profiles of epitaxially doped B and Al in 4H–SiC were investigated after the ion implantation of various species. We found a marked decrease in the atomic B concentration close to the surface in epitaxially B-doped layers after the implantation of Al, N, or P ions followed by annealing at 1700 °C. On the other hand, the Al profiles in epitaxially Al-doped layers were preserved after the same processes.

https://iopscience.iop.org/article/10.1143/JJAP.46.5053/pdf

Abnormal out-diffusion of epitaxially doped boron in 4H-SiC caused by implantation and annealing

In ISPSD 2020 it has been shown that the effective mobility of a lateral 4H-SiC MOSFET could be increased by an order of magnitude through using an ultra-narrow-body design. Thus, this work presents further experimental results on a wide set of fin widths, ranging from conventional (860nm) to ultra-narrow (35nm). Furthermore, a 3D TCAD model, employing quantum corrections, is matched to experiment and applied to study these designs. It is thereby shown that the FinFET effect can have a strong impact in SiC devices and may allow for up to an 18x increase of the mobility relative to a reference width of 280nm. Finally, an optimization window of ~30-50nm is predicted for the fin width, below which the FinFET effect becomes detrimental.

The FinFET effect in Silicon Carbide MOSFETs

Nonpolar AlN layers were grown on 4H-SiC (11¯00) substrates by plasma-assisted molecular-beam epitaxy. By using SiC substrates with well-formed step-and-terrace structures, stable layer-by-layer growth of 4H-AlN (11¯00) can be realized. The layer-by-layer growth is confirmed by observations of anisotropic two-dimensional AlN islands on the grown surface as well as persistent reflection high-energy electron diffraction intensity oscillations. Cross-sectional transmission electron microscopy observations reveal that stacking fault generation during growth is suppressed and the stacking fault density is reduced to 1×106 cm−1.

http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/84574/1/336.pdf

Nonpolar 4H-AlN grown on 4H-SiC (11¯00) with reduced stacking fault density realized by persistent layer-by-layer growth

For further improvement of lateral power devices, 4H-SiC double reduced surface field (RESURF) metal–oxide–semiconductor field-effect transistors (MOSFETs) with high doses in RESURF region have been fabricated and characterized. The drift resistance was decreased and the breakdown voltage was increased with increasing RESURF doses, although breakdown occurs in the oxide when the RESURF doses are too high. The increase of drift resistance in double RESURF MOSFETs at elevated temperature was smaller than that in single RESURF MOSFETs, due to the higher doping concentration in the RESURF region. The fabricated 4H-SiC(0001) double RESURF MOSFETs exhibited a breakdown voltage (VB) of 1540 V and an on-resistance (RON) of 55 mΩ cm2. The figure-of-merit (VB2/RON) of the fabricated device is 43 MW/cm2, which is the highest value compared with those reported in lateral MOSFETs.

https://iopscience.iop.org/article/10.1143/APEX.1.101403/pdf

Improved Performance of 4H-SiC Double Reduced Surface Field Metal--Oxide--Semiconductor Field-Effect Transistors by Increasing RESURF Doses

Planar n-channel MOSFETs have been fabricated on 4H-SiC (11-20), (0001) and (000-1) faces by using oxidation in N2O ambient. The relationship between the MOSFET performance and the acceptor concentration (7×10 15 -2×10 17 cm -3 ) of epilayers has been investigated. 4H-SiC (11-20) MOSFETs have shown a high effective channel mobility of 70 cm 2 /Vs at a 2×10 16 cm -3 doping, and 54 cm 2 /Vs at 2×10 17 cm -3 . Short-channel effects have been also investigated.

Tsunenobu Kimoto

Papers

Abnormal out-diffusion of epitaxially doped boron in 4H-SiC caused by implantation and annealing

The FinFET effect in Silicon Carbide MOSFETs

Nonpolar 4H-AlN grown on 4H-SiC (11¯00) with reduced stacking fault density realized by persistent layer-by-layer growth

Improved Performance of 4H-SiC Double Reduced Surface Field Metal--Oxide--Semiconductor Field-Effect Transistors by Increasing RESURF Doses

High Channel Mobilities of MOSFETs on Highly-Doped 4H-SiC (11-20) Face by Oxidation in N2O Ambient