| 摘要 |
PURPOSE: To provide a negative electrode, of which emission characteristic is improved and of which lifetime is prolonged, by forming a metal matrix for negative electrode made of the alloy, which is composed of platinum group metal at 6% or less and tungsten. CONSTITUTION: This solid-liquid matrix negative electrode is formed of a porous matrix made of the alloy of the fire-resistant metal, which is composed of tungsten and molybdenum, and the transition metal, which is composed of iridium, osmium, rhenium and ruthenium, and soluble alkali earth group mixture oxide to be filled in holes of the matrix, and content of the transition metal is set at 1.0-6.0%. Since the active metal such as iridium exists on an emission surface, work function is reduced, and operating temperature is lowered, and the lifetime of a device is thereby prolonged, and the thermion emitting current is raised. |
