| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain thinning and reduction of electric power, increase joining strength between a heater unit and an electrode member, and thereby improve reliability and durability, by burying adhesively an electrode member for a heater pattern inside a graphite layer for the heater pattern, and by joining the member to the graphite layer for the heater pattern. SOLUTION: A graphite layer for a heater pattern 33 comprising pyrolytic anisotropic graphite is formed on one face 32a of an insulating board 32 comprising pyrolytic anisotropic boron nitride of a heater unit 31. A cathode substrate 34 and a graphite layer for the cathode substrate 35, inside which an electrode member for a substrate metal 36 for the cathode substrate 34 is arranged, buried and joined, are formed on the center part of the other face 326 of the insulating board 32. The graphite layer 33 generates heat by sending a current through an electrode member 37 for the joined heater pattern, and heats the cathode substrate 34 for emitting electron material. Hereby, joining strength between the electrode member 37 and the graphite layer 33 is increased, to thereby improve reliability and durability.</p> |
