Microwave applicators with rotating turntables have been widely applied in many fields, but the heating non-uniformity still limits the further applications. Specifically, when microwave applicators are used to process small batch materials, materials have to be away from the center of rotating turntables, where the problem of heating non-uniformity is more prominent. In order to overcome this difficulty, this paper presents a novel periodical metal cylinder structure to improve the heating uniformity for microwave applicators. With the proposed periodical metal cylinders being placed beneath rotating turntables, electromagnetic fields can be well adjusted, thus improving the heating uniformity. To demonstrate the heating uniformity with the proposed structure, the heating process of the arrays of two and three potato slices in a practical microwave applicator is simulated by the finite element method, respectively. The results show that both the heating uniformity of the two and three potato slices can be improved, which is validated by experiments. Furthermore, the results show that the temperature similarity among the processed potato slices with the proposed structure is better than that without the proposed structure.*

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A 13.5 kV 4H-SiC PiN rectifier with a considerable active area of 0.1 cm2 is fabricated in this paper. Charge-field-modulated junction termination extension (CFM-JTE) has been proposed for satisfying the requirement of ultra-high reverse voltage, which enlarges the JTE dose tolerance window, making it approximately 2.8 times that of the conventional two-zone JTE. Besides, the CFM-JTE can be implemented through the conventional two-zone JTE process. The measured forward current is up to 100 A @ VF = 5.2 V in the absence of carrier lifetime enhancement technology. The CFM-JTE structure accomplishes 96% of the theoretical breakdown voltage of the parallel plane junction with a relatively small terminal area of 400 μm, which contributes to achieving the Baliga’s figure of merit of 58.8 GW/cm2.