%0 Journal Article
%T Batch-Fabricated ¦Á-Si Assisted Nanogap Tunneling Junctions
%A Aishwaryadev Banerjee
%A Carlos H. Mastrangelo
%A Hanseup Kim
%A Rugved Likhite
%A Ryan Looper
%A Samuel Broadbent
%A Shakir-Ul Haque Khan
%J Archive of "Nanomaterials".
%D 2019
%R 10.3390/nano9050727
%X This paper details the design, fabrication, and characterization of highly uniform batch-fabricated sidewall etched vertical nanogap tunneling junctions for bio-sensing applications. The device consists of two vertically stacked gold electrodes separated by a partially etched sacrificial spacer layer of sputtered ¦Á-Si and Atomic Layer Deposited (ALD) SiO2. A ~10 nm wide air-gap is formed along the sidewall by a controlled dry etch of the spacer. The thickness of the spacer layer can be tuned by adjusting the number of ALD cycles. The rigorous statistical characterization of the ultra-thin spacer films has also been performed. We fabricated nanogap electrodes under two design layouts with different overlap areas and spacer gaps, from ~4.0 nm to ~9.0 nm. Optical measurements reported an average non-uniformity of 0.46 nm (~8%) and 0.56 nm (~30%) in SiO2 and ¦Á-Si film thickness respectively. Direct tunneling and Fowler¨CNordheim tunneling measurements were done and the barrier potential of the spacer stack was determined to be ~3.5 eV. I¨CV measurements showed a maximum resistance of 46 ¡Á 103 G¦¸ and the average dielectric breakdown field of the spacer stack was experimentally determined to be ~11 MV/cm
%K nanogap electrodes
%K gold adhesion
%K IOT
%K batch fabrication
%K bio-sensing
%K molecular junctions
%K ¦Á-Si
%K quantum tunneling
%K protein detection
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6567118/