Characteristics of Thin Hf-Silicate Gate Dielectrics after Remote N2 and N2O Plasma Post-Treatments

Abstract

We investigated the thermal stability and physical properties of nitrided Hf-silicate after applying and plasma treatments. The Hf-silicate film was created by remote-plasma atomic layer deposition using and as source gases and plasma as the oxidant. After rapid thermal annealing in ambient, the Hf silicate crystallized at , while Hf-silicate films after the and plasma treatments remained amorphous after annealing at . Remote-plasma treatment of Hf-silicate resulted in a shift of the O 1s peaks to a lower binding energy. The increase in peak intensities of the Si–O–N, Si–O–Hf, and Si–O bonds at the interface after annealing was higher after plasma treatment than after plasma treatment. The accumulation capacitances of an as-grown Hf-silicate metal-oxide-semiconductor structure after plasma treatment show that it has a better capacitance density than the same structure after plasma treatment . The equivalent oxide thickness values for the Hf-silicate films after and plasma treatments are 3.36 and , respectively.