Vertically well-aligned carbon nanotubes (CNTs) are grown on a Ni deposited silicon oxide substrate at 950 o C by thermal chemical vapor deposition using C 2 H 2 . The uniformly grown CNTs with a diameter of about 60 nm have unique beak-like tips without any encapsulated Ni particles inside and exhibit high field emission current density, e.g. 2.9 mA/cm 2 at 3.7 V/μm, following a Fowler-Nordheim behavior.