Effect of Hydrogen Plasma Treatment on Atomic Layer Deposited Silicon Nitride Film

Abstract

Changes in the thin film properties of SiNx deposited via atomic layer deposition using remote N2 plasma were investigated based on the frequency of adding a hydrogen (H2) plasma treatment step during the process. The deposition rate decreased from 0.36 to 0.32 A cycle−1 when compared to SiNx deposited through the conventional deposition process for a thin film that was subjected to H2 treatment processes every 10th cycle, every 5th cycle, and every single cycle of SiNx deposition compared to the deposition process without H2 plasma at a temperature of 400 °C. As the hydrogen treatment process increased beyond a 5:1 ratio, the hydrogen content in the thin film increased based on secondary ion mass spectroscopy analysis, and a change in binding energy state was shown via X-ray photoelectron spectroscopy. The thin film deposited using the hydrogen plasma treatment process at a ratio of 10:1 showed similar characteristics to the SiNx thin film deposited through the conventional atomic layer deposition process and showed excellent etch resistance without an increase in the etch rate. The step coverage characteristics were increased by 16% compared to the deposition process without a H2 plasma treatment process.