Work

Study on Metal-Oxide Field Effect Transistors of β-Gallium Oxide with AlGaO Spacer Layer Grown on Sapphire for High-Power Device Applications

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide This study utilized metal–organic chemical vapor deposition technology to grow β-Ga 2 O 3 epitaxial layers on sapphire substrates and fabricate lateral β-Ga 2 O 3 field-effect transistors (FETs). To enhance the performance of these FETs, a β-Ga 2 O 3 /(Al 0.33 Ga 0.67 ) 2 O 3 structure was incorporated. The resulting FETs demonstrated high on-state current ( I on ), low on-state resistance ( R on ), and a high on–off ratio of drain current, indicating excellent two-dimensional electron gas (2DEG) characteristic offered by β-Ga 2 O 3 /(Al 0.33 Ga 0.67 ) 2 O 3 structure. By optimization of the thickness and doping concentration of β-Ga 2 O 3, high-performance 2DEG β-Ga 2 O 3 FETs were achieved, which satisfied the stringent requirements for power devices. Notably, the heavily doped β-Ga 2 O 3 /(Al 0.33 Ga 0.67 ) 2 O 3 structure led to a significant improvement in performance, with the saturation current ( I D,sat ) increasing from 0.16 to 11.4 mA/mm, a remarkable 6925% increase, and the breakdown voltage rising from 331 to 687 V, an increase of 107.25%. The relative performance of the device with and without AlGaO was also simulated. These enhancements were primarily due to the effective reduction of leakage current density and 2DEG formation by the β-Ga 2 O 3 /(Al 0.33 Ga 0.67 ) 2 O 3 layer, which was grown by the importance of precise growth parameters and structural design in advancing the performance of β-Ga 2 O 3 FETs, making them highly promising for high-power applications.

Source: ACS Applied Electronic Materials

DOI: 10.1021/acsaelm.4c02230