EBIC studies of minority electron diffusion length in undoped p-type Gallium Oxide
Résumé
Minority carrier diffusion length in undoped p-type Gallium Oxide was measured at variable temperatures as a function of electron beam charge injection using Electron Beam-Induced Current technique in-situ in Scanning Electron Microscope. The results demonstrate that charge injection into p-type β-Gallium Oxide leads to a significant linear increase of minority carrier diffusion length followed by its saturation. The effect was ascribed to trapping of non-equilibrium electrons (generated by a primary electron beam) on meta-stable native defect levels in the material, which in turn blocks recombination through these levels. While the previous studies of the same material were focused on probing a non-equilibrium carrier recombination by purely optical means 2 (cathodoluminescence), in this work, the impact of charge injection on minority carrier diffusion was investigated. The activation energy of ~ 0.072 eV, obtained for the phenomenon of interest, is consistent with the involvement of Ga vacancy-related defects.