Low temperature conformal silicon dioxide deposition using supercritical fluid for polymer-based MEMS

A novel supercritical fluid deposition method (SCFD) of SiO
₂
has been developed for polymer-based MEMS. In order to reduce deposition temperature for the application to polymer-based MEMS process, we selected O
₃
as an oxidant in SiO
₂
-SCFD. Conformal SiO
₂
deposition on Si trenches (aspect ratio 24) at low temperatures (below 200°C) was achieved, which were acceptable for deposition on polymers. In addition, SiO
₂
coating on inner wall surface of microchannels, which was made of polydimethylsiloxane (PDMS), was demonstrated.