A novel fabrication method of microcapillaries via silicon surface migration and their application to single cell analysis

We report a novel method of fabricating self-enclosed cylindrical microcapillaries with diameters from 0.8μm to 2.8μm based on silicon surface migration process. Such microcapillaries are conveniently integrated with access ports and microchannels for fluidic functionality. The silicon microcapillary walls oxidized are turned into transparent silica and remain intact upon removal of the surrounding silicon for optical clarity. Perpendicular turns and junctions are introduced without compromising their fluidic continuity. The self-enclosed microcapillaries can be further deposited with epitaxial silicon to raise and smoothen their surface. A raised surface over the microcapillaries prevents unnatural deformation of the cells captured and analyzed at their openings.