Plasma-assisted deposition and characterization of Al2O3 dielectric layers on (001) β-Ga2O3

In this work, we have investigated plasma-assisted deposition of Al2O3 on HVPE (001) beta-Ga2O3 and evaluated the dielectric quality from electrical measurements on fabricated metal-oxide-semiconductor (MOS) capacitors. The interface structure and crystallinity of the films were investigated as a function of the growth temperature. The dielectric/semiconductor interfaces were found to have reverse breakdown electric fields up to 5.3MV/cm in the beta-Ga2O3, with relatively low hysteresis in capacitance-voltage and low leakage current. We determined a negative fixed interface charge density at the interface from analysis of thickness-dependent capacitance voltage data. This study shows the advantage of using plasma-assisted deposition to achieve high breakdown strength Al2O3/beta-Ga2O3 MOS structures for device application purposes.

Automated summary

This work investigates the plasma-assisted deposition of Al2O3 on HVPE (001) beta-Ga2O3 and evaluates the dielectric quality through electrical measurements on fabricated MOS capacitors. The interface structure and crystallinity of the films are studied as a function of the growth temperature. The study demonstrates the advantage of using plasma-assisted deposition to achieve high breakdown strength Al2O3/beta-Ga2O3 MOS structures for device applications.