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. Silicon carbide (SiC) SITs were fabricated using home-grown epi structures. The gate is a recessed gate - bottom contact (RG - B). We designed that the mesa space 2.7μm and the gate channel is 1.2μm. One cell has 400 source fingers and each source finger width is 100μm. 1mm SiC SIT yielded a current density of 123mA/mm of drain current at a drain voltage of 20V. A maximum current density of 150 mA/mm was achieved with Vd=40V. The device blocking voltage with a gate bias of-16 V was 200 V. Packaged 24-cm devices were evaluated using amplifier circuits designed for class AB operations. A total power output in excess of 213 W was obtained with a power density of 8.5 W/cm and gain of 8.5 dB at 500 MHz under pulse operation.

This article introduces the study of peripheral clamping for large-aperture laser mirrors in high power laser facilities. Some multi-point clamping schemes were experimentally tested, the results of the experiments show that these schemes cannot meet the technical requirements, and in the simulation analysis, we explain the reason for this phenomenon. It is concluded that the additional bending moment caused by the non-ideal process factors in the multi-point clamping is the main cause for the surface distortion. Based on the above conclusions, we carried out research on minor-point clamping. Experimental verification of the minor-point clamping were done, the results show that the minor-point clamping can meet the requirements of technical indicators in whole process. This work can provide a reference for the design of the large-aperture transport mirror clamping structure, which may be used in huge laser devices and telescopes.

600V-30A 4H-SiC Junction Barrier Schottky（JBS）diodes were designed and fabricated using SiC epitaxy and device technology. SiC JBS diodes were packaged in Si IGBT module，and switching measurements were done at 125°C. As free-wheeling diode for Si IGBT, 600V SiC JBS diode was compared to 600V ultra-fast diode from International Rectifier. SiC diode achieved 90% recovery loss reduction and corresponding IGBT showed 30% lower turn-on loss. However, SiC JBS diode has larger on-state voltage drop due to small chip area. On-state power loss will be lowered by increasing SiC chip area.

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