This article presents fabrication and characterization results for a diamond field emission diode with high emission current. Techniques such as high-temperature diamond brazing and a special anode with an "indented-edge" design were developed to achieve a microsized vacuum diode with high electron emission current. A diamond field emission diode with a moderately low turn-on electric field of 6 V/mum and a high emission current of similar to22 mA at an electric field of similar to16 V/mum has been achieved. The high total emission current capability of this diamond vacuum diode is attributed to the ability to produce a uniform diamond emitter configuration by the molding method, the utilization of a high-temperature diamond brazing technique and the indented-edge anode design, along with the inherent high thermal conductivity of diamond material. These factors enable the high emission current potential of diamond field emitters to begin to be observed. This work suggests that diamond pyramidal microtip arrays are promising candidates for high emission current cathodes. (C) 2003 American Vacuum Society.