ON THE INVERSION IN GAAS METAL-INSULATOR-SEMICONDUCTOR HETEROSTRUCTURES

We report the discovery that thr [111] strained Si (similar to 10 Angs trom) as an interlayer between Si3N4 and (111) GaAs may allow the Ferm i level to fully scan the GaAs conduction band and induct inversion el ectrons in GaAs. The band structure calculations indicate that the str ained 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 levers i n the quantum well formed by Si3N4/Si/(111)GaAs are almost unconfined and those of Si3N4/Si/Al0.3Ga0.7As/(111)GaAs are confined, but the con fined energy level in Si conduction band is similar to 0.1 eV higher t han the GaAs conduction band. Both structures may induce inversion ele ctrons in GaAs potentially paving the way for the realization of GaAs based n-channel inversion mode metal-insulator-semiconductor transisto rs. (C) 1997 American Institute of Physics.