Ultra-Wide Bandgap β -Ga 2 O 3 Heterojunction Field-Effect Transistor Using p-Type 4H-SiC Gate for Efficient Thermal Management

The low thermal conductivity and the absence of effective acceptors limit the potential utility of β -Ga 2 O 3 electronics. Herein, to generate an n-channel β -Ga 2 O 3 heterojunction field-effect transistor (FET) with efficient thermal management, n-type β -Ga 2 O 3 as a channel layer was integrated with p-type 4H-SiC as both a gate and a thermal drain via van der Waals interaction. The n-p β -Ga 2 O 3 /4H-SiC heterojunction displayed typical rectifying behavior with an ideality factor of 1.4 and a rectification ratio of ∼10 7 . The fabricated β -Ga 2 O 3 heterojunction FET operated in depletion mode with current saturation above the pinch-off voltage, which is consistent with the results of numerical device simulation. Excellent output and transfer characteristics were observed, including no hysteresis, low subthreshold swing (∼114 mV dec −1 ), and a high output current on/off ratio (∼…