| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a resistance value necessary for break protection and emission characteristics in high control and high reproducibility by forming a resistor with high resistance at low specific resistance. SOLUTION: A resistance layer 14 is formed on a conductive substrate 11 which becomes a cathode through an insulating layer 13, a gate electrode 2 is formed thereon through an insulating layer 10, a plurality of opening part 8 are formed in part of the resistance layer 14, and a cone-shaped emitter cone 5 is formed within the opening part 8. The resistance layer 14 consists of an emitter forming region 15 and a plurality of resistors 15' equally arranged along the outer periphery of the region 15, and each resistor is electrically connected to the conductive substrate 11. The emitter cone positioned in the outermost circumference of the emitter cone 5 is arranged so that the resistance length is made equal to each resistor 15' of the resistance layer 14. The resistor with high resistance at low specific resistance can be used in the resistance layer 14.</p> |
