GaN-based super-lattice Schottky barrier diode with low forward voltage of 0.81V

Abstract

In this paper, we report a high-performance AlGaN/GaN Schottky barrier diode (SBD) based on super-lattice structure. The stacking of five AlGaN/GaN heterostructures yields a small sheet resistance ( R SH ) of 120 Ω/sq. The fully recessed anode structure is used to contact all the current channels, leading to a small turn-on voltage ( V ON ) of 0.44 V. Besides, the ohmic contact with a contact resistance ( R C ) of 0.17 Ω mm is obtained by etching the cathode region. The on-resistance ( R ON ) of the device is reduced by 63.8%, down to 1.7 Ω mm, and a forward voltage ( V F ) as low as 0.81 V is achieved. To the best of our knowledge, this V F is the lowest value among all the GaN SBDs. These results are superior to the conventional single heterojunction devices , showing the great potential of the GaN-based super-lattice structures for achieving low forward conduction losses. • The super-lattice structure yields a small sheet resistance, and the on-resistance of the device is reduced by 63.8%. • A contact resistance of 0.17 Ω mm is obtained by etching the cathode region with designed depth. • The fully recessed anode contacts all the current channels, leading to a small turn-on voltage of 0.44 V. • A forward voltage as low as 0.81 V and an on-resistance down to 1.7 Ω·mm have been achieved.