Scaling of InAlN/GaN power transistors

This work presents the first use of InAlN/GaN high electron mobility transistors in power electronic applications. High voltage transistors of various gate widths (W_g) have been fabricated to observe how transistors scale. The high charge density enabled by the InAlN/GaN heterostructure has the potential to reduce the on-resistance of GaN power transistors, compared to the standard AlGaN/GaN structures. Transistors with maximum gate width of W_g=39.6 mm have been fabricated in this study and they showed a total current I_{D max} of 18.57 A and specific on-resistance of R_ON,sp=1.497mΩ·cm². In all these devices, the maximum drain voltage, transconductance, and gate-source capacitance scale well, however the off-state current and gate leakage show a super-linear increase with scaling gate width. The demonstration of transistors with large gate widths and high current levels is promising for use in actual circuit applications.