| 摘要 |
<p>PURPOSE:To operate an electron emitting device, which is usable for an electron beam generating source of a various kinds of electron beam apparatus such as an electron microscope, etc., at low voltage and improve its properties and stabilize the emission of electrons. CONSTITUTION:A base electrode 12 is formed on a substrate 11. A cathode connecting part 13 is formed on a prescribed part of the base electrode 12 and a cathode part 14 is formed on the part. The back side periphery of the cathode part 14 has a mesa-like shape having an edge part with a sharp cross- section and has a wedge part whose width changes gradually. An insulating layer 16 is formed in the position in a prescribed distance from the wedge part of the cathode part 14 and a controlling electrode 17 is formed on the insulating layer 16. Since the cross-section shape of the wedge part 15 of the cathode part 14 is made sharp, the electric field converging degree is increased. Since the wedge part 15 of the cathode part 14 is extruded toward side of the cathode connecting part 13, the electric field convergence into an unnecessary site does not occur.</p> |
