Analysis of Leakage Currents through PLD Grown Ultrathin a-LaGdO3 Based High-k Metal Gate Devices

Abstract

ABSTRACTA detailed analysis of leakage current density-gate voltage measurements of gate stacks composed of PLD grown ultra thin films of LaGdO3 (LGO) on p-type silicon substrates with 8.4 Å EOT is presented. Temperature dependent leakage measurements revealed that forward bias current was dominated by Schottky emission over trap assisted tunneling below 1.2 MV/cm and quantum mechanical tunneling above this field. The physical origin of the reverse bias current was found to be a combination of Schottky emission and trap assisted tunneling. Low leakage current densities in the range from 2.3×10-3 to 29×10-3 A/cm2 were recorded for films with EOT from 1.8 to 0.8 nm, that are at least four or more orders below the ITRS specifications and its SiO2 competitors.