The characteristics of the diamondlike carbon (DLC) films deposited on Au-coated silicon substrate are observed to vary markedly with the substrate temperature. Large relative proportion of sp(3)-bonds had pronouncedly improved the electron emission properties of the DLC films. A low turn on field as 7 V/mu m and a large emission current density as 2000 mu A/cm(2), at 20 V/mu m, were achieved for DLC/Au/Si films deposited at 200 degrees C. Too high a substrate temperature (i.e., 600 degrees C) induced graphitization that degraded the field emission behavior. The DLC/Au/Si films grow in a similar behavior as DLC/Mo/Si films, but possess substantially better field emission characteristics. The scanning electron microscopic and secondary ion mass spectroscopies analyses implied that the main factor is the improvement on the interfacial structure through the interdiffusion between DLC, Au, and Si layers.