Planar Nanostrip-Channel Al2O3/InAlN/GaN MISHEMTs on Si With Improved Linearity

In this work, a 100 nm-gate Al2O3/InAlN/GaN metal-insulator-semiconductor high electron mobility transistor (MISHEMT) with a planar nanostrip-channel was fabricated on a Si substrate and its DC, small-signal RF and two-tone intermodulation characteristics were measured. The use of a planar nanostrip-channel and MIS structure allows these devices to have close to 10 dB better intermodulation distortion than traditional InAlN/GaN high electron mobility transistors. In addition, the GaN planar nanostrip-channel MISHEMT shows five orders of magnitude lower gate current Ig, 30% higher current drivability and much improved gmand fTgate voltage swing than a planar nanostrip-channel GaN HEMT with a Schottky gate. This allows the planar nanostrip-channel GaN MISHEMT to be able to operate at higher input gate voltage (more than Vg= +4 V) and achieve higher output current with better linearity performance.