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 authors have investigated effects of thermal oxidation on deep levels in the whole energy range of the band gap of 4H–SiC by deep level transient spectroscopy. The deep levels are generated by ion implantation. The dominant defects in n-type samples after ion implantation and high-temperature annealing at 1700 °C are IN3 (Z1/2: EC−0.63 eV) and IN9 (EH6/7: EC−1.5 eV) in low-dose-implanted samples, and IN8 (EC−1.2 eV) in high-dose-implanted samples. These defects can remarkably be reduced by thermal oxidation at 1150 °C. In p-type samples, however, IP8 (HK4: EV+1.4 eV) survives and additional defects such as IP4 (HK0: EV+0.72 eV) appear after thermal oxidation in low-dose-implanted samples. In high-dose-implanted p-type samples, three dominant levels, IP5 (HK2: EV+0.85 eV), IP6 (EV+1.0 eV), and IP7 (HK3: EV+1.3 eV), are remarkably reduced by oxidation at 1150 °C. The dominant defect IP4 observed in p-type 4H–SiC after thermal oxidation can be reduced by subsequent annealing in Ar at 1400 °C. These pheno...

/pdf/reduction-of-deep-levels-generated-by-ion-implantation-into-4iob1x9u11.pdf

Reduction of deep levels generated by ion implantation into n- and p-type 4H–SiC

Electrical behavior of implanted Al and B near implant-tail region in 4H–SiC (0001) after high-temperature annealing has been investigated. Depth profiles of Al and B acceptors determined by capacitance-voltage characteristics are compared with those of Al and B atoms measured by secondary-ion-mass spectrometry. For Al+ (aluminum-ion) implantation, slight in-diffusion of Al implants occurred in the initial stage of annealing at 1700°C. The profile of the Al-acceptor concentration in a “box-profile” region as well as an “implant-tail” region is in good agreement with that of the Al-atom concentration, indicating that nearly all of the implanted Al atoms, including the in-diffused Al atoms, work as Al acceptors. Several electrically deep centers were formed by Al+ implantation. For B+ (boron-ion) implantation, significant out- and in-diffusion of B implants occurred in the initial stage of annealing at 1700°C. A high density of B-related D centers exists near the tail region. In the tail region, the sum of B-acceptor concentration and D-center concentration corresponds to the B-atom concentration. C+ (carbon-ion) coimplantation with a ten times higher dose than B+ effectively suppressed the B diffusion, but additional deep centers were introduced by C+ coimplantation.

/pdf/carrier-compensation-near-tail-region-in-aluminum-or-boron-1bnyxvddqr.pdf

Carrier compensation near tail region in aluminum- or boron-implanted 4H-SiC(0001)

4H-SiC pn photodiodes were fabricated and the temperature dependence of the photoresponse was measured for various wavelengths (280–365 nm) as a function of reverse-bias voltage. A temperature-independent photoresponse was obtained at 280 nm illumination from room temperature to 300 °C under zero-bias condition. By applying reverse-bias voltage up to 150 V, the wavelength of the temperature-independent photoresponse was varied from 280 to 300 nm. The temperature-independent photoresponse was explained by the temperature dependence of optical absorption coefficient together with surface recombination effect.

https://iopscience.iop.org/article/10.1143/APEX.5.094101/pdf

4H-SiC pn Photodiodes with Temperature-Independent Photoresponse up to 300 °C

Anisotropy of Inversion Channel Mobility in 4H- and 6H-SiC MOSFETs on (11-20) Face

We report on the critical thickness of AlN on SiC(0001). AlN was directly grown on 6H-SiC(0001) at 650 °C by rf-plasma-assisted molecular beam epitaxy. The growth layer had a relatively low threading dislocation density of 4×108–4×109 cm-2. Although the critical thickness of AlN on SiC(0001) is estimated to be 3.5 nm using a Matthews–Blakeslee model, the critical thickness in our experiment was over 700 nm. Low dislocation density, a layer-by-layer growth mode, and low growth temperature may contribute to such a large critical thickness. Sharp and intense free exciton emission was observed in low-temperature PL measurements of the AlN layer.

https://iopscience.iop.org/article/10.1143/APEX.5.105502/pdf

Tsunenobu Kimoto

Papers

Reduction of deep levels generated by ion implantation into n- and p-type 4H–SiC

Carrier compensation near tail region in aluminum- or boron-implanted 4H-SiC(0001)

4H-SiC pn Photodiodes with Temperature-Independent Photoresponse up to 300 °C

Anisotropy of Inversion Channel Mobility in 4H- and 6H-SiC MOSFETs on (11-20) Face

Over-700-nm Critical Thickness of AlN Grown on 6H-SiC(0001) by Molecular Beam Epitaxy