| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a highly practical element, which can sufficiently discharge electrons even by low impressed voltage, by constructing the element of an amorphous carbon film consisting of a specific content of Cs. SOLUTION: This cold cathode element is constructed of an amorphous carbon film containing 0.1-5.0 atom. % of Cs. If there is a possibility of exposure to the atmosphere, the Cs content is 1.8 atom. % or less. On the surface of the amorphous carbon film, Cs oxide is scattered, and desirably, the amorphous carbon film is formed by an ion beam deposition method using anion beams. When a specific quantity of Cs is contained in the amorphous carbon film, discorderd structure is generated inside the film because of a difference of an atomic radius between a C atom and a Cs atom, so that an electric insulating property of the film is reduced while its conductivity is increased. On the other hand, Cs inside the film exhibits effect lowering a work function of C. In this way, a discharge electric field of the cold cathode element (amorphous carbon film) is lowered, so that sufficient electrons can be discharged even by low impressed voltage.</p> |
