Trap states and hydrogenation of implanted Si in semi-insulating Ga₂O₃(Fe) Available to Purchase

The electrical properties and deep trap spectra of semi-insulating Ga₂O₃(Fe) implanted with Si ions and subsequently annealed at 1000 °C were investigated. A significant discrepancy was observed between the measured shallow donor concentration profile and the profile predicted by Stopping Power and Range of Ions in Matter simulations, indicating substantial compensation. Deep level transient spectroscopy revealed the presence of deep acceptors at E_c −0.5 eV with a concentration of ∼10¹⁷ cm⁻³, insufficient to fully account for the observed compensation. Photocapacitance spectroscopy identified additional deep acceptors with optical ionization thresholds near 2 and 2.8–3.1 eV, tentatively attributed to gallium vacancy-related defects. However, the combined concentration of these deep acceptors still fell short of explaining the observed donor deactivation, suggesting the formation of electrically neutral Si-vacancy complexes. Furthermore, the properties of Ga₂O₃ (Fe) implanted with Si and subjected to hydrogen plasma treatment at 330 °C were also examined. This material exhibited high resistivity with the Fermi level pinned near E_c –0.3 eV, similar to common radiation defects in proton-implanted Ga₂O₃. A prominent deep center near E_c −0.6 eV, consistent with the known E1 electron trap attributed to Si-H complexes, was also observed. These results highlight the challenges associated with Si implantation and activation in Ga₂O₃ and suggest that hydrogen plasma treatment, while effective for Ga-implanted Ga₂O₃ is less suitable for Si-implanted material due to the formation of compensating Si-H complexes.