Field emission from diamond micropowders with sharp edges

Wide-bandgap materials, such as SiC, BN, and diamond, have attracted attention for use in field emission devices because of their low or even negative electron affinity (NEA). The electron emission characteristics of a field emission device strongly depend on the tip sharpness. It is difficult to fabricate a conventional cone-shaped emitter using SiC, BN, and diamond because of their chemical and physical stabilities. We have reported that the sharp edges of SiC and BN micropowders function as field emission sources 1)2) . Field emission from diamond micropowders has also attracted interest for application to field emission devices; however, this has not been demonstrated until now. In this study, we investigate field emission from diamond micropowders and show that they work well as field electron emission sources.