Schottky barrier height dependence on the compensation doping in the interfacial Si layer of Al/Si/n:GaAs Schottky diodes

Abstract

Al/Si/n:GaAs Schottky diode structures have been grown by molecular-beam epitaxy utilizing thin (100 Å) Si interfacial layers. These Si layers are unintentionally very heavily n-type doped with As from the system or from the substrate. This n-type doping is intentionally compensated with p-type (Al) doping during the growth of the Si layer in an attempt to modulate the Schottky barrier height. The resultant barrier height, as determined by I-V and C-V measurements, increases with increased acceptor doping in the Si (from 0.34 eV for no Al doping to a maximum of 1.07 eV) as per Poisson’s equation.