Diamond coated Spindt-type arrays for emission enhancement

Summary form only given, as follows. Conventional field emitters require fields of ~5 MV/cm to produce emission. It has been observed recently that CVD diamond produces cold field emission at applied fields ~20 kV/cm. Spindt type arrays have been fabricated at NASA Lewis to investigate cold field emission for space communication applications. There has been much effort to integrate the field emission properties of diamond with the proven Spindt-type cathode design. A technique has been developed which utilizes Biased-Enhanced-Nucleation (BEN) and allows CVD diamond growth to take place on only the Mo tips of the Spindt-type array. The diamond coating can be doped with various materials which might enhance field emission from the tips. Previous device designs utilizing N-doped diamond have produced current densities of up to 10 A/cm² with 100 V applied bias. Spindt-type cathodes are operated before and after diamond coatings to assess the emission enhancement