AlGaN/GaN FinFET With Extremely Broad Transconductance by Side-Wall Wet Etch

AlGaN/GaN-based fin-shaped field-effect transistors with very steep side-wall have been fabricated by utilizing electron-beam lithography and subsequent anisotropic side-wall wet etch in tetramethyl ammonium hydroxide solution. The investigate device demonstrated extremely broad transconductance (g(m)) ranging from similar to 0 to similar to 8 V at V-D = 10 V, which is essential for high linearity device performance. Pulse measurement showed that the device exhibits negligible gate lag, but still suffers from drain lag. The device with L-GD of 17 mu m exhibited excellent OFF-state characteristic with subthreshold swing of similar to 58 mV/decade, low OFF-state leakage current of similar to 10(-12) A, and breakdown voltage of similar to 400 V at V-G = -9 V.