Effects of BCl3 passivation on Pt/Al/n-InP diodes

Abstract

High performance Schottky diodes formed with a BCl3 passivation layer on Pl/Al/n-InP are presented. The diode realizes a barrier height as high as 0.85 eV, and the reverse current density is 1.44 x 10(-6) A/cm(2) at -3 V. Secondary ion mass spectroscopy for depth profiles measurements reveals the existence of B and Cl elements at the contact interface. The electron spectroscopy chemical analysis shows that the surface layer of the passivated InP substrate is composed of InPO4 and chloride. The improvement of the barrier height of Pt/Al/n-InP diode is presumably due to the formation of the aluminum oxide at the contact interface and due to the chlorine passivation on the interface states.