Publication details
Nanometer-scale interface instability in silicon oxide/polymer sandwich structures detected after two years
| Authors | |
|---|---|
| Year of publication | 2025 |
| Type | Article in Periodical |
| Magazine / Source | Materials Chemistry and Physics |
| MU Faculty or unit | |
| Citation | |
| web | https://doi.org/10.1016/j.matchemphys.2025.130935 |
| Doi | https://doi.org/10.1016/j.matchemphys.2025.130935 |
| Keywords | Plasma-enhanced chemical vapor deposition; (PECVD); Interface; Porosity; Diffusion; Silica; Polymer; Carbon dioxide |
| Description | Nonthermal plasma-deposited glassy silica is often used as a gas barrier film to protect polymer material in many applications. This study revealed that glassy silica is a slightly porous material (3 vol%) with small pores (2.5 nm) formed during thin film deposition. The infrared spectrum shows that the as-deposited plasma silica contains gaseous carbon dioxide, which is likely encapsulated in the pores. It can be assumed that these CO2 molecules diffuse from the silica layer through the silicon oxide/polymer interface into the protected polymer material. The low crosslinked polymer material is then locally oxidized by CO2, which changes its chemical and physical properties. This means that the silicon oxide/polymer interface gradually moves into the polymer material over time. CO2 diffusion is therefore considered responsible for a shift of the silicon oxide/polymer interface by 30–35 nm after 27 months. |