THE EFFECT OF THE PLANAR DOPING ON THE ELECTRICAL TRANSPORT-PROPERTIES AT THE ALN-GAAS(100) INTERFACE - ULTRAHIGH EFFECTIVE DOPING

Measurements of the current density as a function of the applied bias have been performed to study the electronic properties of the Al:n-GaAs(100) interface. The samples were grown by molecular beam epitaxy. A Si planar doping was placed in GaAs(100) at different depths underneath the metal-semiconductor interface and the charge transport across this interface has been investigated. An increasing tunneling contribution to the net current through the Schottky barrier has been observed by decreasing the planar doping depth. For sufficiently small depths, the tunneling current dominated. Planar doping near the metal-semiconductor interface was found to be equivalent, concerning charge transport properties, to a bulk semiconductor doped well beyond the currently achievable limit.