Ultramet coatings for dielectric, insulative, conductive, and controlled work function materials deliver superior electron emission properties and can be applied to refractory substrates including molybdenum, niobium, tungsten, and silicon carbide. Dielectric coatings such as tantalum pentoxide and titanium oxide and insulators such as boron nitride and silicon nitride are available.
The following coatings developed for other applications are excellent choices for contacts and conductors:
| Tungsten | Platinum |
| Rhenium | Nickel |
| Iridium | Refractory carbides and nitrides |