Nanometer‐Scale Depth‐Resolved Atomic Layer Deposited SiO2 Thin Films Analyzed by Glow Discharge Optical Emission Spectroscopy

Abstract

In this contribution, pulsed radio frequency (rf) glow discharge optical emission spectroscopy (GDOES) is used to investigate the film properties of SiO2 deposited by plasma enhanced atomic layer deposition (PEALD), for example, the chemical composition, structural properties and film thickness. The total sputtering time until the interface between the SiO2 layer and the Si substrate is ≈13 s. The main impurities in the film, that is, H, C, and N, are detected. It is observed that both C and N intensities decrease with increasing plasma power during deposition of the thin film. The higher plasma power seems to increase the reactivity of the PEALD process and consequently, it might reduce the concentration of impurities in the deposited film. Moreover, the deviation of the GDOES sputtering rates on the film are related to the film density. The thickness of one‐hundred‐nanometer range SiO2 film is calculated from the GDOES silicon and oxygen emission profiles, and its difference from ellipsometry and X‐ray reflectivity measurements highlights the challenges for the GDOES technique for transparent thin films.