J. H. Zhao

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A latest developed normally-off SiC JFETs has been characterized under static and dynamic operating conditions. Two application oriented inverter circuits were constructed for additional tests under and soft- and hard-switching conditions. The single-phase soft-switching inverter was running at 100 kHz, and the three-phase hard-switching inverter was(More)
This paper reports the design, fabrication and characterization of high voltage 4H-SiC merged PiN/Schottky-barrier (MPS) diodes with an active area of 1.4mm. For comparison purposes, Schottky barrier, PiN and MPS diodes of smaller size (8.1x10mm) have also been designed and fabricated on the same wafer with a 30μm, n=2x10cm doped drift layer. The Schottky(More)
– This paper reports the first demonstration of a 9.2kV 4H-SiC bipolar junction transistor (BJT) based on a 50 μm, 7x10cm doped drift layer, achieving an emitter current density of 150A/cm at VCEO=5V. A much larger area BJT of identical wafer design with negligible current spreading effect would have an RSP_ON equal to 49mΩ-cm limited only by the specific(More)
This paper presents the design, fabrication and characterization of 4H-SiC trenched-andimplanted vertical JFETs (TI-VJFETs) [1]. The design of TI-VJFETs with active areas of 9.38×10 -2 mm 2 and 2.03mm 2 and different vertical channel openings is presented based on a blocking layer of 9.4μm, doped to n=7x10 15 cm -3 . Highly vertical channel defined by(More)
The measured photomultiplication and excess noise characteristics of two 4H-SiC p-i-n diodes, with i-region widths of 0.105 μm and 0.285 μm, were modelled using a nonlocal multiplication model to determine the ionization threshold energies and the impact ionization coefficients of 4H-SiC. The modelled ionization coefficients accurately predicted the(More)
A high voltage 4H-SiC bipolar junction transistor (BJT) has been developed with 16 A, 600 V rating. This paper presents a new base drive structure for the SiC BJT for inverter application. The driver consists of one IGBT and one MOSFET to help turn-on and turn-off of the SiC BJT transistor in a Darlington like configuration. Instead of using conventional(More)
Abstract. This paper demonstrates the first 4H-SiC metal-semiconductor-metal (MSM) UV photodetector. Two types of MSM photodetectors are fabricated for comparison: one in p-type 4HSiC and the other in n-type 4H-SiC. The n-type SiC photodetectors show a low dark current less than 10nA at -15V bias while the p-type ones show a lower dark current of 0.3nA at(More)
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