Quasibound states of electric field-induced quantum wells in silicon subsurfaces

Quasibound states of a nontriangular quantum well in the silicon subsurface layer induced by an intense surface electric field are directly calculated on the basis of generalized Airy functions to obtain the field emission current from the silicon surface. The subband energy level and the resonance width of the quasibound state can be simultaneously derived from the complex eigenenergy of the system. By comparing the results for the nontriangular quantum well to those for the triangular quantum well with a finite depth obtained using the Blatt-Weisskopf approximation, it is shown that the triangular quantum well model is not valid under intense surface electric fields.