Vertically self-aligned conical carbon nanofibers by pulsed discharge plasma chemical vapour deposition and its field electron emission

Vertically self-aligned conical carbon nanofibers were deposited on silicon coated with thin film of cobalt (100 nm) using pulsed discharge plasma chemical vapor deposition at 400-450°C. Possible mechanism of their growth is discussed. FE-SEM observations indicate that they are self vertically well aligned, with an average diameter of about 200 nm at the bottom and with a tip of about 70 to 100 nm in diameter. HR-TEM, visible Raman and XRD study reveals that the nanofibers have an amorphous structure and are made of diamond like carbon. Field electron emission study indicates a low turn-on field of about 1.4 V/μm and threshold field of about 4.2 V/μm, suggesting their possible application as field electron emitters. KGaA.