Origin of the self-limited electron densities at Al₂O₃/SrTiO₃ heterostructures grown by atomic layer deposition - oxygen diffusion model.

Recently, 2-dimensional electron gas (2-DEG) was discovered at the interface of Al₂O₃/SrTiO₃ (STO) heterostructures, in which the amorphous Al₂O₃ layers were grown by atomic layer deposition (ALD). The saturated electron density at the Al₂O₃/STO heterostructures above the critical thickness of Al₂O₃ is explained by an oxygen diffusion mechanism.