Effects of post‐deposition annealing on chemical composition of SiNx film in SiO2/SiNx/SiO2/Si stacked structure. (21st February 2022)

• Record Type: Journal Article
• Authors: Sakata, Tomohiro; Ogawa, Shingo; Inoue, Keiko; Shimizu, Yumiko; Tanahashi, Yusaku
• Is Part Of: Surface and interface analysis. Volume 54:Number 6(2022)
• Page Start: 661
• Page End: 666
• Publication Date: 2022-02-21
• Subjects: Fourier transform infrared spectroscopy -- post‐deposition annealing -- scanning transmission electron microscope–electron energy loss spectroscopy -- silicon nitride -- stacked structure -- X‐ray photoelectron spectroscopy -- X‐ray reflectivity; Surfaces (Physics) -- Periodicals; Surface chemistry -- Periodicals; Thin films -- Periodicals; 541.33
• DOI: 10.1002/sia.7078
• Languages: English
• ISSNs: 0142-2421

Abstract

Abstract : To systematically evaluate the quality of SiNx films in multi‐stacked structures, we investigated the effects of post‐deposition annealing (PDA) on the film properties of SiNx within the SiO2 /SiNx /SiO2 /Si stacked structure by performing X‐ray photoelectron spectroscopy (XPS), X‐ray reflectivity (XRR), Fourier transform infrared (FT‐IR) spectroscopy, and scanning transmission electron microscope–electron energy loss spectroscopy (STEM‐EELS) analyses. The XPS results showed that PDA induces the oxidation of the SiNx layer. In particular, new finding is that Si‐rich SiNx in the SiNx layer is preferentially oxidized by PDA even in multi‐stacked structure. The XRR results showed that the SiNx layer becomes thinner, whereas the interface layer between the SiNx layer and Si becomes thicker. It is concluded by STEM‐EELS and XPS that this interface layer is SiON layer. The density of N–H and Si–H bonding within the stacked structure strongly depends on the PDA temperature. Our study helps elucidate the properties of SiNx films in stacked structures from various perspectives.