title: Probing liquid surfaces under vacuum using SEM and ToF-SIMS.
abstract: We report a newly developed self-contained interface for high-vapor pressure liquid surfaces to vacuum-based analytical instruments. It requires no wires or tubing connections to the outside of the instrument and uses a microfluidic channel with a 3 μm diameter window into the flowing fluid beneath it. This window supports the liquid against the vacuum by the liquid's surface tension and limits the high-density vapor region traversed by the probe beams to only a few microns. We demonstrate this microfluidic interface for in situ liquid surfaces in a time-of-flight secondary ion mass spectrometer (ToF-SIMS) and a scanning electron microscope (SEM) with chemical analysis.
authors.affiliation: Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Yu
authors.forename: Zihua
authors.initials: Z
authors.lastname: Zhu
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Iedema
authors.forename: James P
authors.initials: JP
authors.lastname: Cowin
mesh_terms: D046210:Microfluidic Analytical Techniques; D008855:Microscopy, Electron, Scanning / Q000295:instrumentation / Q000379:methods; D018629:Spectrometry, Mass, Secondary Ion / Q000295:instrumentation / Q000379:methods*; D014618:Vacuum