We observed the emission characteristics and stability of TiN-coated Si field emitter arrays (FEAs) with a TIW gate structure. The TiN layer on Si tips was formed by a two-step rapid thermal nitridation process in an NH3 ambient by which a Ti layer was thermally converted to a TiN/TiSi2 bilayer. This process could suppress the formation of TiO2 on the surface and make the TiN layer thicker than a one-step process. By coating Si tips with TiN, the operating voltage of the TiN-coated Si FEAs was reduced by about 20 V compared with non-coated ones. Also, the TiN-coated Si FEAs showed thermally stable electron emission compared with non-coated ones.