【Domestic Papers】New progress of Associate Professor Man Hoi Wong at the Hong Kong University of Science and Technology —— A landscape of β-Ga₂O₃ Schottky power diodes

      By PhD. Man Hoi Wong from the Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology have published a dissertation titled "A landscape of β-Ga₂O₃ Schottky power diodes " in Journal of Semiconductors.

Abstract: 

      β-Ga₂O₃ Schottky barrier diodes have undergone rapid progress in research and development for power electronic applications. This paper reviews state-of-the-art β-Ga₂O₃ rectifier technologies, including advanced diode architectures that have enabled lower reverse leakage current via the reduced-surface-field effect. Characteristic device properties including on-resistance, breakdown voltage, rectification ratio, dynamic switching, and nonideal effects are summarized for the different devices. Notable results on the high-temperature resilience of β-Ga₂O₃ Schottky diodes, together with the enabling thermal packaging solutions, are also presented.

Fig. 1. (a) Schematic of the first field-plated β-Ga₂O₃ SBD. (b) Forward current–voltage (I–V) characteristic of the device. (c) Reverse breakdown characteristic of the device.

Fig. 2.  (a) Schematic of a β-Ga₂O₃ SBD with an ultrahigh-permittivity field-plate dielectric, where S1 corresponds to a 15-period BaTiO₃/SrTiO₃ superlattice as the field-plate oxide [(BTO/STO)₁₅ FP] and S2 corresponds to BaTiO₃ as the field-plate oxide (BTO FP). The cross-sectional transmission electron microscopy image depicts the field-plated region of the S1 structure. (b) Forward I–V characteristics and differential R_ON,sp of a β-Ga₂O₃ SBD with (BTO/STO)₁₅ FP, a β-Ga₂O₃ SBD with BTO FP, and a reference SBD without a field plate. (c) Reverse breakdown characteristics of the three different SBD structures.