Author ORCID Identifier
Year of Publication
Master of Science in Electrical Engineering (MSEE)
Electrical and Computer Engineering
Dr. J. Todd Hastings
Electron-beam induced deposition (EBID) is a position-controlled technique that can directly fabricate nanometer-sized structures in functional materials. In the standard process, a gaseous precursor delivers the desired substance to the substrate for deposition. However, the material purity from these precursors is typically poor, which often negatively affects the functional properties of the deposit. Recently, bulk liquid precursors have been investigated as promising reactants for high purity deposition without the need for post-processing. In this work, EBID from bulk liquids is shown to yield highly conductive nanowire deposits. Aqueous solutions containing copper sulfate (CuSO4) and sulfuric acid (H2SO4) are used as precursors to deposit copper nanowires on oxidized silicon substrates in an environmental scanning electron microscope (ESEM). Using four point I-V measurement, our results show a copper resistivity as low as 67 μΩ⦁cm, which is 6-8 orders of magnitude lower than that of as-deposited copper from gas phase reactants, 4-5 orders of magnitude lower than that of annealed materials, and within 1 order of magnitude of bulk copper. The low resistivity of these deposits without post-processing highlights the importance of further research to overcome challenges associated with deposition via liquid precursors, such as collateral deposition; local delivery of the reactant; and control of liquid thickness.
Digital Object Identifier (DOI)
Syam, Amjad M., "ELECTRON BEAM INDUCED DEPOSITION OF HIGHLY CONDUCTIVE COPPER NANOWIRES FROM BULK LIQUIDS" (2016). Theses and Dissertations--Electrical and Computer Engineering. 96.