Temperature dependence of silicon nitride deposited by remote plasma atomic layer deposition

Abstract

We investigated the characteristics of silicon nitride (SiN x ) thin films deposited by remote plasma atomic layer deposition (RPALD) using trisilyamine (TSA) and ammonia (NH 3 ) plasma at low temperatures. Although the process window of SiN x thin films is 150?350?°C, considering the refractive index (RI), SiN x thin films deposited at 250?350?°C were focused on for analyses. All of the SiN x films were nearly stoichiometric, regardless of the deposition temperature. As the deposition temperature increased, the RI increased, while the hydrogen content decreased. The defect density also changed at higher deposition temperatures; as the deposition temperature increased, all of the trap densities increased because of the low?hydrogen content in the SiN x thin films. The characteristics of the SiN x thin film deposited by RPALD could be controlled to adjust the defect density for charge trap flash memory applications by changing the deposition temperature.