Overcoming evanescent field decay using 3D-tapered nanocavities for on-chip targeted molecular analysis

摘要

Overview image of the device with plasmonic wave propagation and confinement at the end of three-dimensionally tapered tip. Open cavity allows fluidic delivery and surface functionalization enabling molecular capture. Device fabrication using a silicon wafer with 1 μm thick thermally grown silicon dioxide, gold deposition, and FIB milling. Zoomed-in view of the 3D-tapered nanocavity tip. Schematic showing an array of 3D-tapered nanocavities with a hydrophilic silica base. SEM image showing fabricated arrays of 3D-tapered nanocavities with hydrophilic silica base. Scale bar is 25 µm. A single 3D-tapered nanocavity. Scale bar is 2 µm. Sharp 3D-tapered naocavity tip. Scale bar is 200 nm.