On the inversion in GaAs metal-insulator-semiconductor heterostructures

We report the discovery that the [111] strained Si (∼ 10 Å) as an interlayer between Si₃N₄ and (111) GaAs may allow the Fermi level to fully scan the GaAs conduction band and induce inversion electrons in GaAs. The band structure calculations indicate that the strained Si on (111) GaAs or (111) AlGaAs has a much wider band gap (0.87 eV) than the strained Si on (001) GaAs (0.34 eV). The energy levels in the quantum well formed by Si₃N₄/Si/(111)GaAs are almost unconfined and those of Si₃N₄/Si/Al_0.3Ga_0.7AS/(111)GaAs are confined, but the confined energy level in Si conduction band is ∼0.1 eV higher than the GaAs conduction band. Both structures may induce inversion electrons in GaAs potentially paving the way for the realization of GaAs based n-channel inversion mode metal-insulator-semiconductor transistors.