Demonstration of Large-Size Vertical Ga₂O₃ Schottky Barrier Diodes

Large-size vertical β-Ga ₂ O ₃ Schottky barrier diodes (SBDs) with various device areas were demonstrated on a Si-doped n-type drift layer grown by hydride vapor phase epitaxy (HVPE) on bulk Sn-doped (001) n-type β-Ga ₂ O ₃ substrate. In this letter, the devices have two circular contacts with a diameter of 1500 and 500 μm and two square contacts with dimensions of 1600 × 1600 μm ² and 800 × 800 μm ² , corresponding to the area of 0.2 × 10 ^-2 cm ² (the smallest device), 0.6 × 10 ^-2 , 1.8 × 10 ^-2 , and 2.6 × 10 ^-2 cm ² (the largest device). The breakdown voltage (BV) was determined to be -261 V for the largest device and -427 V for the smallest device. Also, the ideality factor (η) of vertical Ga ₂ O ₃ SBDs with different device areas exhibited the same value of 1.07, except for the largest device area of 2.6 × 10 ^-2 cm ² with an ideality factor of 1.21. At an applied forward bias of VF= 2 V, the specific on-state resistance (RonA) of all the Ga ₂ O ₃ SBDs remains relatively low with values ranging from 1.43 × 10 ^-2 Ω cm ² to 7.73 × 10 ^-2 Ω cm ² . The measured turn-on voltage (Von) of all the SBDs remains low with a narrow distribution.