Papers by Keyword: SI-SiC

Abstract: Non-water taphole clay was prepared by using high alumina ((Al2O3)>85%,Particle Size is 3~1, ≤1 mm),coke, clay, kyanite, Ferrosilicon Nitride Powder and Corundum powder, adding more 15% tar as the binder and Si-SiC (0,4%,8%,12%) to replace Ferrosilicon Nitride. Specimens with dimensions of φ50mm × 50mm and 125mm × 25mm × 25mm were prepared under a uniaxial pressure of 5MPa. The microstructure, high temperature bending strength (600oC,800 oC,1000 oC,1200 oC,1400 oC) and apparent porosity and sinter ability of the tap hole clay were studied. The influence of the substitution content of Si-SiC of the tap hole Clay was also investigated. The results showed that the high temperature bending strength of the samples decreased with the increasing of Si-SiC and apparent porosity almost no changing, but it could still met the need of the actual requirement. The Si-SiC substitution content within 5% of the tap hole clay has also good performance. Through the analysis of the microscopic structure of the tap hole clay, the tap hole clay with Si-SiC has good sinter ability.

Abstract: AlGaN/GaN HFETs were fabricated around micropipes and on a domain boundary in a semi-insulating silicon carbide (SI-SiC) substrate and the DC characteristics of the fabricated devices were measured. Devices around micropipe showed no pinch-off or large gate leakage. The devices on the domain boundaries showed no degradation in the performances, even though an X-ray topographic analysis indicated that crystal imperfections, due to the defects, propagated to the GaN layer across the hetero interface. Based on these results, we concluded that micropipe degrades the DC characteristics and that the domain boundary does not affect the DC characteristics. From Raman analysis on the devices around the micropipes, these degradations could be attributed to the free carriers introduced into the GaN crystal by the micropipes.