title: Glass microfabricated nebulizer chip for mass spectrometry.
abstract: A microfluidic nebulizer chip for mass spectrometry is presented. It is an all-glass device which consists of fusion bonded Pyrex wafers with embedded flow channels and a nozzle at the chip edge. A platinum heater is located on the wafer backside. Fabrication of the chip is detailed, especially glass deep etching, wafer bonding, and metal patterning. Various process combinations of bonding and metallization have been considered (anodic bonding vs. fusion bonding; heater inside/outside channel; metallization before/after bonding; platinum lift-off vs. etching). The chip vaporizes the liquid sample (0.1-10 microL min(-1)) and mixes it with a nebulizer gas (ca. 100 sccm N2). Operating temperatures can go up to 500 degrees C ensuring efficient vaporization. Thermal insulation of the glass ensures low temperatures at the far end of the chip, enabling easy interconnections.
authors.affiliation: Micro and Nanosciences Laboratory, Helsinki University of Technology, P.O. Box 3500, FI-02015 TKK, Finland. ville.saarela@tkk.fi
authors.forename: Ville
authors.initials: V
authors.lastname: Saarela
authors.forename: Markus
authors.initials: M
authors.lastname: Haapala
authors.forename: Risto
authors.initials: R
authors.lastname: Kostiainen
authors.forename: Tapio
authors.initials: T
authors.lastname: Kotiaho
authors.forename: Sami
authors.initials: S
authors.lastname: Franssila
mesh_terms: D005898:Glass; D056656:Lab-On-A-Chip Devices; D013058:Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*; D046208:Microchip Analytical Procedures / Q000379:methods*