Characteristics of ZrO2 gate dielectrics on O2- and N2O-plasma treated partially strain-compensated Si0.69Ge0.3C0.01 layers

Abstract

The characteristics of ZrO2 gate dielectric along with the interfacial layer on O2- and N2O-plasma treated partially strain-compensated Si0.69Ge0.3C0.01∕Si heterostructures have been investigated using spectroscopic and electrical measurements. Time-of-flight secondary ion mass spectroscopy and x-ray photoelectron spectroscopy analyses show the formation of an oxygen or nitrogen rich Zr-germanosilicate interfacial layer between the deposited ZrO2 and SiGeC films. The electrical and charge trapping properties under a constant current stressing have been studied using a metal-oxide-semiconductor structure. The N2O-plasma treated SiGeC film has a higher effective dielectric constant (k∼14) than that of the O2-plasma treated (k∼12) films. The equivalent areal densities of charge defects, Neq (cm−2), are found to be ∼1.8×1012 and ∼6×1011cm−2 for O2- and N2O-plasma treated films, respectively. Considerably less trapped charges in the N2O-treated gate dielectric stack under constant current stressing make it highly attractive for SiGeC based scaled metal-oxide-semiconductor device applications.

Charge trapping characteristics of atomic-layer-deposited HfO2 films with Al2O3 as a blocking oxide for high-density non-volatile memory device applications

“…Relative permittivities of HfO 2 and Al 2 O 3 films are found to be ∼17 and ∼8, respectively, after a high temperature annealing treatment at ∼1000 • C for 10 s in N 2 ambient. Assuming the permittivity of ∼3.9 of SiO 2 , relative permittivities of pure HfO 2 and Al 2 O 3 films are calculated using p-Si/SiO 2 (3 nm)/HfO 2 (10 nm)/Al and p-Si/SiO 2 (3 nm)/Al 2 O 3 (10 nm)/Al stack capacitor structures, respectively, with the series capacitance method[26]. The high-frequency (100 kHz) capacitance is used to calculate the relative permittivity.…”