Effects of rapid thermal annealing on structure and electrical properties of Gd-doped HfO2 high k film

Abstract

Effects of rapid thermal annealing (RTA) at 950 °C for 5 s in N2 on structure and electrical properties of Gd-doped HfO2 film deposited on Si(100) substrates have been studied. RTA causes partial crystallization of Gd-doped HfO2 film and slight reduction in band gap. Silicide appears in the interfacial layer and thickness of interface layer increases. Keeping Gd-doped HfO2 films at about 3 nm, the leakage current density is 3.81×10−5 A/cm2 at 1 V gate voltage without RTA while that is 8.50×10−2 A/cm2 with RTA. The permittivities are ∼14.8 and ∼17.9 and the capacitance equivalent thicknesses are 1.6 nm and 1.1 nm for the samples with and without RTA, respectively.