Electrophoretic Deposition of Carbon Nanotubes on Silicon Substrates

• Main Author: Sarkar, Anirban
• Other Authors: Hung, Francisco R.
• Format: Others
• Language: en
• Published: LSU 2013
• Subjects: Electrical & Computer Engineering
• Online Access: http://etd.lsu.edu/docs/available/etd-08192013-205130/

This dissertation research describes the feasibility study and investigation of Electrophoretic Deposition (EPD) of carbon nanotubes (CNTs) for applications in semiconductor research. In recent years, the EPD technique has been considered as an economical, room temperature, solution based wet coating technique for thin and thick CNT films on arbitrary substrates. In this study, fabrication of uniform coatings of acid-treated CNTs has been pursued on bare silicon substrates by EPD from aqueous and organic suspensions. Research endeavors are extended to examine EPD of CNTs on silicon substrates with various surface coatings such as metal (aluminum), insulator layers (silicon dioxide and silicon nitride) and self-assembled polar organosilane (APTES) molecules. Microstructural imaging, spectroscopic analysis and characterization of the morphology of the CNT films have also been reviewed in relation to the deposition parameters such as inter-electrode electric field, deposition duration and APTES concentration. For research and development involving advanced spectroscopic analysis, Surface Enhanced Raman Spectroscopy (SERS) studies have been conducted on horizontally aligned EPD fabricated porous CNT networks coated with silver nanoparticles (AgNPs). The acquired Raman spectra of AgNP-CNT hybrid nanostructures display significant enhancement in the Raman intensity values of Rhodamine6G (R6G) analyte by several orders of magnitude with respect to the reference sample. Improvement in the Raman signals has pushed the detection limit to as low as 1 × 10^-12 M. The experimental results, reported in this dissertation, thus establish the novelty of EPD in the fabrication of the AgNP coated porous CNT substrate for routine SERS analysis of different target analytes.