title: Microfluidic liquid jet system with compatibility for atmospheric and high-vacuum conditions.
abstract: We present microfluidic chip based devices that produce liquid jets with micrometer diameters while operating at very low flow rates. The chip production is based on established soft-lithographical techniques employing a three-layer design protocol. This allows the exact, controlled and reproducible design of critical parts such as nozzles and the production of nozzle arrays. The microfluidic chips reproducibly generate liquid jets exiting at perfect right angles with diameters between 20 μm and 2 μm, and under special circumstances, even down to 0.9 μm. Jet diameter, jet length, and the domain of the jetting/dripping instability can be predicted and controlled based on the theory for liquid jets in the plate-orifice configuration described by Gañán-Calvo et al. Additionally, conditions under which the device produces highly reproducible monodisperse droplets at exact and predictable rates can be achieved. The devices operate under atmospheric and under vacuum conditions making them highly relevant for a wide range of applications, for example, for free-electron lasers. Further, the straightforward integration of additional features such as a jet-in-jet is demonstrated. This device design has the potential to integrate more features based on established microfluidic components and may become a standard device for small liquid jet production.
authors.affiliation: Physical Chemistry 1, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany. stephan.foerster@uni-bayreuth.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Trebbin
authors.forename: Kilian
authors.initials: K
authors.lastname: Krüger
authors.forename: Daniel
authors.initials: D
authors.lastname: DePonte
authors.forename: Stephan V
authors.initials: SV
authors.lastname: Roth
authors.forename: Henry N
authors.initials: HN
authors.lastname: Chapman
authors.forename: Stephan
authors.initials: S
authors.lastname: Förster
mesh_terms: D001274:Atmospheric Pressure; D004867:Equipment Design; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008853:Microscopy; D012235:Rhodamines / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D014618:Vacuum
chemical_list: D012235:Rhodamines; D012997:Solvents; C029773:rhodamine B