Barium strontium oxide functionalized carbon nanotubes thin film thermionic emitter with superior thermionic emission capability
Despite their potential, thin film thermionic emitters are yet to appear in real device applications. The main shortcoming for thin film thermionic emitters is their weak emission capability as compared to conventional thermionic cathodes. In this study, a high performance thin film thermionic emitter with emission capability on par with that of a conventional thermionic cathode is presented. This thin film emitter combines a large Schottky effect induced by the carbon nanotubes with a low work function oxide surface coating, resulting in a dramatic increase of thermionic emission. Emission current density as high as 4.5 A/cm2 was obtained at a typical thermionic emission temperature of 1380 K. The growth and fabrication techniques for this emitter are also compatible with the silicon process, making it possible to incorporate this thin film thermionic emitter into other semiconductor devices for potential new device applications.