Optimization of plasma-enhanced chemical vapor deposition parameters for the growth of individual vertical carbon nanotubes as field emitters

In this article plasma enhanced growth of single vertical carbon nanotubes (CNTs) from individual nickel catalyst dots is studied, aiming at the fabrication of CNT field emitters. It is found that the growth of individual CNTs differs from that of CNT forests grown from unpatterned catalyst films, an effect that can be attributed to the difference in catalyst volumes. In the context of growth parameters the influence of temperature, growth time, catalyst volume, pressure and power is characterized. After determining the growth behavior, an individual CNT of desired geometry is fabricated on a conducting lead. The CNT is electrically characterized in terms of its field emission behavior and stable emission currents and its work function is determined to Φ = 5.4 ± 0.2 eV.