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

We found that carbon-associated byproducts formed at the dry-oxidized SiO2/SiC(0001) interface could be decomposed and emitted on the SiO2 side by high-purity Ar annealing. We measured the concentration of ejected carbon atoms in SiO2 by secondary ion mass spectrometry, and found that it strongly depended on the condition of oxide formation (dry-oxidation, nitridation treatment, and phosphorus treatment). This work provides indirect but unambiguous evidence for the formation of carbon byproducts at the SiO2/SiC interface, and indicates that phosphorus treatment removes these byproducts, leading to a significant reduction in interface defects.

Carbon ejection from a SiO2/SiC(0001) interface by annealing in high-purity Ar

Spiral growth by chemical vapor deposition (CVD) on 6H-SiC (0001) has been investigated by atomic force microscopy (AFM). The carbon-to-silicon (C/Si) ratio for CVD strongly affects the shape of spiral hillocks. The change in shape originates from the change in the relative rates of spiral growth and step-flow growth: a high C/Si ratio enhances spiral growth, while a low C/Si ratio enhances step-flow growth.

https://iopscience.iop.org/article/10.1143/JJAP.42.L846/pdf

Effect of C/Si Ratio on Spiral Growth on 6H-SiC (0001)

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

Design and formation of SiC (0001)/SiO2 interfaces via Si deposition followed by low-temperature oxidation and high-temperature nitridation

The temperature dependence of the refractive indices of 4H-SiC, GaN, and AlN were determined in a wavelength range from the near band edge (392 nm for 4H-SiC, 367 nm for GaN, and 217 nm for AlN) to infrared (1700 nm) and a temperature range from room temperature to 500 °C. Optical interference measurements with vertical incidence along a c-axis configuration were employed to precisely evaluate ordinary refractive indices. Near the band-edge region, the temperature dependence of the refractive index mainly originates from the temperature change of the bandgap. At 450 nm, the thermo-optic coefficients of 4H-SiC, GaN, and AlN were measured to be 7.8 ×10-5, 1.6 ×10-4, and 3.6 ×10-5 K-1, respectively.

http://iopscience.iop.org/article/10.1143/JJAP.51.112101/pdf

Thermo-Optic Coefficients of 4H-SiC, GaN, and AlN for Ultraviolet to Infrared Regions up to 500 ?C

Ultrahigh-voltage 4H-SiC PiN diodes with improved junction termination extension (JTE) structures have been investigated. Breakdown characteristics of 4H-SiC PiN diodes with conventional single-zone JTE was shown to be severely affected by the charge near the SiO 2 /SiC interface from experiment and device simulation. Taking the effect of the interface charge into account, and by using “Space-Modulated” JTE structure with a wide optimum JTE-dose window to tolerate the impact of interface charge, we achieved a breakdown voltage of 21.7 kV (81 % of the ideal breakdown voltage calculated from the epilayer structure), which is the highest breakdown voltage among any semiconductor devices ever reported.

Tsunenobu Kimoto

Papers

Carbon ejection from a SiO2/SiC(0001) interface by annealing in high-purity Ar

Effect of C/Si Ratio on Spiral Growth on 6H-SiC (0001)

Design and formation of SiC (0001)/SiO2 interfaces via Si deposition followed by low-temperature oxidation and high-temperature nitridation

Thermo-Optic Coefficients of 4H-SiC, GaN, and AlN for Ultraviolet to Infrared Regions up to 500 ?C

Breakdown characteristics of 12–20 kV-class 4H-SiC PiN diodes with improved junction termination structures