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 thermal decomposition and hydrogen etching of a 6H-SiC(0001) Si-face were directly monitored using an in situ gravimetric monitoring system. The monitoring of the weight change of the 6H-SiC Si-face using this system clarified the dependences of the thermal decomposition and hydrogen etching rates on the substrate temperature. Although the thermal decomposition of the 6H-SiC Si-face above 1400 °C generated a graphite layer since only the Si atom directly desorbs from the surface, the etching of the 6H-SiC Si-face by hydrogen did not form this layer, and both Si and C atoms react with hydrogen. Moreover, the surface reaction of the 6H-SiC Si face with H2 and the resultant surface morphology were found to change at approximately 1250 °C.

https://iopscience.iop.org/article/10.1143/JJAP.48.095505/pdf

In situ Gravimetric Monitoring of Thermal Decomposition and Hydrogen Etching Rates of 6H-SiC(0001) Si Face

https://iopscience.iop.org/article/10.35848/1882-0786/ab7f16/pdf

Theoretical analysis of band structure effects on impact ionization coefficients in wide-bandgap semiconductors

In this paper, we have investigated reliability of n- and p-type 4H-SiC(0001) metal–oxide–semiconductor (MOS) devices with N2O-grown oxides and deposited oxides annealed in N2O. From the results of time-dependent dielectric breakdown (TDDB) tests, it is revealed that the N2O-grown oxides have relatively-high reliability (4–30 C cm-2 for n- and p-MOS structures). In addition, the deposited SiO2 on n- and p-SiC exhibited a high charge-to-breakdown of 70.0 and 54.9 C cm-2, respectively. The n/p-MOS structures with the deposited SiO2 maintained a high charge-to-breakdown of 19.9/15.1 C cm-2 even at 200 °C. The deposited SiO2 annealed in N2O has promise as the gate insulator for n- and p-channel 4H-SiC(0001) MOS devices because of its high charge-to-breakdown and good interface properties.

https://iopscience.iop.org/article/10.1143/JJAP.50.090201/pdf

Reliability of Nitrided Gate Oxides for N- and P-Type 4H-SiC(0001) Metal–Oxide–Semiconductor Devices

The interface structures of 4H‐SiC/6H‐SiC heterostructures formed in monocrystalline bulk silicon carbide were studied by high‐resolution electron microscopy of cross‐sectional specimens. The samples were grown on the (0001) C face of a 6H‐SiC seed with in situ Ce doping. The observed transition region is atomically flat over regions of several hundreds nm. The transition from the initial 6H‐SiC growth to the 4H‐SiC growth happens all at once at certain thicknesses with the occurrence of only a few layers of 4H‐SiC (6H‐SiC) before (after) the transition. The atomic stacking sequence at the interface of the two polytype crystals can be resolved.

4H-SiC/6H-SiC interface structures studied by high-resolution transmission electron microscopy

Nonpolar 4H-polytype AlN/AlGaN multiple quantum well (MQW) structures were grown on 4H-SiC(1100) substrates by molecular-beam epitaxy. Layer-by-layer growth of MQW layers is observed and abrupt AlN/AlGaN interfaces have been achieved. Generation of additional extended defects is not observed at the AlN/AlGaN interfaces and the crystal structure of 4H-polytype is preserved throughout the entire MQW structure. In cathodoluminescence spectra, a band-edge emission peak is observed at 5.41 eV (229 nm). The band edge peak position is not blue-shifted when the irradiation beam current is increased.

https://iopscience.iop.org/article/10.1143/APEX.3.051001/pdf

Tsunenobu Kimoto

Papers

In situ Gravimetric Monitoring of Thermal Decomposition and Hydrogen Etching Rates of 6H-SiC(0001) Si Face

Theoretical analysis of band structure effects on impact ionization coefficients in wide-bandgap semiconductors

Reliability of Nitrided Gate Oxides for N- and P-Type 4H-SiC(0001) Metal–Oxide–Semiconductor Devices

4H-SiC/6H-SiC interface structures studied by high-resolution transmission electron microscopy

Nonpolar 4H-Polytype AlN/AlGaN Multiple Quantum Well Structure Grown on 4H-SiC(1100)