Sub-micrometer plasma-enhanced chemical vapor deposition using an atmospheric pressure plasma jet localized by a nanopipette scanning probe microscope

We developed a localized plasma-enhanced chemical vapor deposition (PE-CVD) technique to deposit silicon oxide with a sub-micrometer width on a substrate using an atmospheric pressure plasma jet (APPJ) irradiated from a nanopipette nozzle. To realize fine material deposition, hexamethyldisiloxane (HMDSO) vapor was blown into the localized helium APPJ irradiated from the sub-micrometer aperture of the nanpopipette with the jet length limited to the aperture size of the nanopipette. The irradiation distance was controlled using a shear-force positioning technique using scanning probe microscopy (SPM). The proposed system successfully deposited silicon oxide dots with sub-micrometer width on a substrate. After the deposition, the topography of the deposited surface was observed by scanning the nanopipette, which can be used as an SPM probe. The localized PE-CVD properties were systematically investigated by varying the deposition parameters. The amount of deposited material could be controlled by the flow rate of the carrier gas of the HMDSO vapor, APPJ irradiation time, and nanopipette–substrate surface irradiation distance.