  This article presents a new class of batch-fabricated, low-power and highly
sensitive chemiresistive sensors. We first present the design, fabrication and
characterization of batch-fabricated sidewall etched vertical nanogap
tunnelling-junctions for bio-sensing. Using these devices we demonstrate the
electrical detection of certain organic molecules from measurements of
tunneling characteristics of target-mediated molecular junctions formed across
nanogaps.
