Electrophoretic Deposition of Carbon Nanotubes on Silicon Substrates

In recent years, the electrophoretic deposition (EPD) technique has been viewed as an attractive method for depositing carbon nanotube (CNT) thin films at room temperature, mostly on metal substrates. In this study, EPD has been performed to obtain deposits of CNTs on silicon substrates with various surface coatings. The process resulted in CNT film thicknesses up to similar to 15 mu m on metal-coated silicon samples. The nanotubes exhibited preferential deposition and adhesion exclusively on the metal surfaces even when the direct-current (DC) voltage was supplied only to the silicon substrate, which was electrically isolated from the metal layer. The effects of electric field, deposition time, and underlying films on the thickness and surface roughness of the CNT film were studied. The adhesion strength of the CNT film was studied as well. The results obtained demonstrate the great potential of EPD of CNT thin films for a wide range of applications.