Field Plated AlGaN/GaN-on-Si HEMTs for High Voltage Switching Applications

In this study, we have fabricated AlGaN/GaN-on-Si HEMTs for high voltage switching applications where both field plate length and gate-to-drain distance were varied for structural optimization. A tapered gate was fabricated in conjunction with the field plate in order to effectively suppress the high electric field at the gate edge. Regardless of the gate-to-drain distance that was varied from 7 to 20 μm, the highest breakdown voltage was obtained with a short field plate length (i.e., 2 - 3 μm) and the breakdown voltage monotonically decreased with increasing the field plate length. The breakdown voltage of 1200 V with the on-resistance of 3.7 mΩ.cm^2 was achieved using the gate-to-drain distance of 20 μm and the field plate length of 3 μm. KCI Citation Count: 12