SurfaceScience21 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 8: Poster Session I: Solid-liquid interfaces: Structure, spectroscopy
O 8.9: Poster
Montag, 1. März 2021, 10:30–12:30, P
Hydration of Polyvinyl Alcohol Surfaces Mediated by Ammonia — Takahiko Ikarashi1, Takumi Yoshino1, Naoki Nakajima1, Kazuki Miyata1, Keisuke Miyazawa1, •Ygor Morais Jaques2, Adam S. Foster2, Megumi Uno3, Chikako Takatoh3, and Takeshi Fukuma1 — 1Kanazawa University, Japan — 2Aalto University, Finland — 3EBARA Corporation, Japan
Chemical mechanical planarization (CMP) is a process that smooths silicon wafers surface for their efficient use in electronics. This procedure results in the surfaces being covered by silica nanoparticles. An effective way of removing these debris is by scrubbing polyvinyl alcohol (PVA) brushes on the wafer’s surface in an aqueous solution. However, this can cause cross-contamination between wafers due to debris adhesion into the PVA surface. Thus, for an optimal technical setup, the interactions between silica nanoparticles and PVA as well as PVA’s hydration in different liquids have to be properly addressed. Here, we investigate the hydration of PVA in NH3 aq. and pure water. Using atomic force microscopy, we found that the adhesion force between a silica tip and a PVA surface in NH3 aq. is drastically reduced when compared to the system immersed in water. Using molecular dynamics simulations, we have found that this happens because the NH3 molecules perturb the hydrogen bond networks formed between water and the PVA hydroxyl groups, promoting faster interactions and diffusion. This central role of ammonia in the inhibition of nanoparticle adhesion can further improve post CMP cleaning processes.