Brief Discussion on Basketball Movement and Its Developmental Trend

<p>On the basis of having adequate information about basketball movement, and in the face of the changeable, poly-type, multi-class and diversified developmental trend of the basketball movement in the modern society, this paper summarizes the development and advantages of the basketball movement. This provides better popularization and reference for the basketball movement.</p>

Structure of Straight-Line Defect and its Effect on the Electrical Properties of Schottky Barrier Diodes

We have investigated the “straight-line defect,” which has not been classified separately and is quite similar to the carrot defect. We found that the straight-line defect differed structurally from the carrot defect. The presence of a particle on the substrate-epi layer interface seemed to be the cause of the defect; a layer of poly-type (3C-SiC) extended from the particle to the epi-layer surface. The straight-line defect likely resulted from shape change from the 3C-SiC triangular defect. This change in shape from triangular to straight-line defects depended on the C/Si ratio. To investigate the electrical characteristics, we fabricated a Schottky barrier diode (SBD) structure on a silicon carbide (SiC) epi wafer. With application of a high voltage, destruction occurred on both the upstream and the downstream side of the step flow of straight-line defects in the reverse voltage test. This reverse direction characteristic differed from that observed with triangular defects.

3D Raman Spectroscopy Investigation of Defects in 4H-SiC Epilayer

In this report we were able to successfully identify and localize in 3D 3C and 6H foreign polytypes and stress in the embedded epilayer by high resolution 3D Raman spectroscopy, that were otherwise invisible under the microscope or SEM, in non-contact and non-destructive way. Stripe patterned deep trenches with aspect ratio about 2 (depth=3.0μm; width=1.5μm) were formed on 4H-SiC substrate by ICP. The epitaxial layer was embedded in these trenches by SiC CVD. Poly type defects and stress in the embedded epilayer were mapped by curve-fitting of spectra obtained from Raman measurement of the embedded SiC epilayer. The location of the foreign polytypes and the stress inside the stripe pattern allows speculating on the origin of the defects and correlating it to the manufacturing process.

TEM Observation of Defect Structure of Low-Energy Ion Implanted SiC

The aim of this review is to present the observation of low-energy ion implanted SiC and annealing them by using TEM. By detail analyses of the TEM images and results of SRIM, ion implanted SiC was classification four structure depending on the ion concentration in a few ten nm shallow region. This results suggest that crystal structure in a few nm shallow region can be controled by concentration of the ion implant. And SiC was re-crystallized single poly-type after annealed at 1500°C. But, defects in end of amorphous region affect to recover the damaged structure .

4H-SiC Digital Logic Circuitry Based on P+ Implanted Isolation Walls MESFET Technology

The design and development of SiC integrated circuits (ICs) nowadays is a necessity due to the increasing demand for high temperature intelligent power applications and intelligent sensors. Due to the superior electrical, mechanical and chemical proprieties of 4H-SiC poly-type, 4H-SiC MESFET transistor is a good compromise for ICs on SiC able to work at higher temperatures (HT) than on Si. This paper presents new experimental results of approaching embedded logic gates with SiC MESFETs and resistors, built in junction-isolated tubs. The P+ implantation isolation technology offers important perspectives regarding the integration density of devices per unit area and wafer surface, being able to use far more complex design geometry for modeling ICs on SiC.

Raman Spectroscopy and XPS Analysis of Epitaxial Graphene Grown on 4H-SiC (0001) Substrate under an Argon Pressure of 900 mbar Environment

This paper investigated a feasible process of growing epitaxial graphene on 4H hexagonal poly-type of silicon carbide Si-faced polar surface (0001) under an argon pressure of 900 mbar conditions. Using Raman Spectroscopy, Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy, epitaxial graphene grown at temperature 1600°C is confirmed to take shape weakly on 4H-SiC (0001) with an average domain size of several tens of nanometers, and this can be seen as the characteristic of initial formation of epitaxial graphene on substrate.

New Method for In-Trench Pipeline Support

Protection of the pipe during and after pipeline construction is of paramount importance for safety and pipeline integrity. Areas of rock and stone are often encountered during construction of new pipelines. Even with modern pipeline coatings, additional protection for the pipe is necessary where rock or stone exposure is significant. Historically, additional pipe protection used in these types of situations is achieved through adding either a significant layer of sand or select backfill above and below the pipeline (sand padding) and/or by attaching a high-impact resistant, poly-type rock shield around the pipeline during the pipeline installation process. To accommodate sand padding, some form of intermittent support of the pipeline is generally required to elevate the pipeline off the trench bottom. Similar intermittent support is also recommended practice when using poly-type rock shields to keep the pipeline from fully resting on trench rocks. Current methods of in-trench support involve sand piles, sand bags, spray foam and individually formed foam pillows — each with drawbacks: i) Sand Piles are difficult to install and often oval or dent the pipe when improperly placed. ii) Sand bags require hand placement for proper support. In open trenches, this can be time consuming and unsafe. Improper placement can cause the pipe to oval or dent. iii) Spray-in foam is considered to be an obstruction of cathodic protection currents. Newly constructed pipelines full of hydrostatic test water and one metre cover can cause foam to compress excessively. iv) Foam pillows are light and easily placed — but can float out of position and compress or crack under heavy loads. As with all foam, cathodic shielding is always a concern. A new, engineered method of in-trench pipeline support is now available — the Structured Pipeline Pillow (SPP). SPP’s are injection molded and made from high strength, environmentally inert polypropylene or polyethylene resins. Designed to support any size pipeline, SPP’s are most effective with larger diameter, heavier pipelines. One SPP is engineered to carry a single 40′ joint of heavy wall pipeline filled with hydrostatic test water. Compared with current methods, SPP’s: i) Stack tightly for transport. ii) Are light enough for installation from outside the trench and resist floatation when ground water is present. iii) Help ensure the pipeline is centered in the trench during the pipeline installation. iv) Maintain long-term pipe clearance above rocky trench bottoms. v) Ovality and denting concerns are reduced. vi) Allow cathodic protection an easy path to the pipeline. vii) Will never biodegrade. In their extended stacking mode, SPP’s tested well as an effective alternative to wooden skids for many situations such as pipe stockpiling; stringing along the rights-of-way (ROW); and even for some low level skidding during the welding process.

Structure Analysis of In-Grown Stacking Faults and Investigation of the Cause for High Reverse Current of 4H-SiC Schottky Barrier Diode

Two types of structures related to in-grown SF having a different influence on reverse currents of 4H-SiC SBDs were investigated. One type contained only a single SF formed by 1c of 8H poly-type and showed low reverse currents. The other type was accompanied with short SFs which consisted of 3C poly-type in addition to two SFs formed by 1c of 8H poly-type and showed high reverse currents. SF formed by 1c of 8H poly-type was not the cause of the high reverse current, and we speculate that the barrier height lowering at the short SF attributed to the high reverse currents of SBDs.

Crystalline Recovery after Activation Annealing of Al Implanted 4H-SiC

Crystalline recovery mechanism in the activation annealing process of Al implanted 4H-SiC crystals were experimentally investigated. Annealing temperature and annealing time dependence of acceptor activation and activated hole’s behavior were examined. Poly-type recovery from the implantation induced lattice disordering during the annealing was investigated. The existence of meta-stable crystalline states for acceptor activation, and related scattering centers due to annealing is reported To achieve 100% acceptor activation and to reduce strain after ion implantation, annealing at 2000°C for 10 min. was required.