High dose carbon implantation into Si tip array was performed to synthesize SiC/Si heterostructure tip array. This was done using a high beam current density metal vapor Vacuum are ion source. Silicon tip arrays were prepared by anisotropic chemical etching. An implantation energy of 35 keV using a dose of 1.0 x 10(18) ions/cm(2) was performed. The array was subsequently annealed in argon ambient at 1200 degrees C, for various times to form the SiC surface layer. Scanning electron microscopy shows that the Si tips were sharp and uniformly arranged. X-ray photoelectron spectroscopy confirmed that a thin SiC surface layer had been formed. Results show that electron emission properties measured in ultrahigh vacuum depended on the sample treatment. A typical turn-on field was 15 V/mu m when the emission current density reaches 1 mu A/cm(2). This compares with a turn-on field of about 35 V/mu m for an unimplanted Si tip array.