AlGaN/GaN Metal-Oxide-Semiconductor High-Electron Mobility Transistors Using Ga2O3 Gate Dielectric Layer Grown by Vapor Cooling Condensation System

In this study, intrinsic Ga2O3 (i-Ga2O3) film was deposited at about 80 K using a vapor cooling condensation system. Its bandgap energy was 5.0 eV. Low oxygen vacancy and defects were verified by using photoluminescence and Hall measurements. When a 40-nm-thick i-Ga2O3 film was used as the gate dielectric layer of AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors (MOS-HEMTs), threshold voltage, and gate breakdown voltage were - 3.5 V and - 538.0 V, respectively. The associated gate leakage current of the devices operating at a gate-source voltage of - 100 V was 0.57 mu A. Furthermore, a saturation drain-source current of 186.2 mA/mm and a maximum extrinsic transconductance of 85.8 mS/mm were obtained for the devices operating at a gate-source voltage of 0 V and a drain-source voltage of 10 V. The unit gain cutoff frequency and the maximum oscillation frequency were 5.7 GHz and 11.0 GHz, respectively. The normalized noise and Hooge's coefficient were 3.79 x 10(-14) Hz(-1) and 5.06 x 10(-5), respectively, when the devices operated at a frequency of 100 Hz, with a drain-source voltage of 1 V and a gate-source voltage of 5 V.

Automated summary

In this study, intrinsic Ga2O3 film with a bandgap energy of 5.0 eV was successfully deposited and used as the gate dielectric layer in high-electron mobility transistors, exhibiting excellent electrical performance.