| 摘要 |
<p>PURPOSE: To enhance the dielectric withstand voltage by forming a cavity centering on the tip of an emitter electrode in an insulating film deposited on a base board whose oversurface is electrically conductive. CONSTITUTION: The surface of a base board 1 whose oversurface is electrically conductive, is subjected to gas phase growth or heat oxidation so that an insulative layer 2 is formed, which is followed by photolithography process to produce an opening 7. The surface of the base board 1 is subjected to a gas phase growing process so that an insulative layer 3 is formed, and the surface of the insulating layer 3 is subjected to gas phase growth, vacuum evaporation, or sputtering so that an electroconductive film 4' is produced, which is provided with an opening 8 concentrically with the opening 7, and thus a gate electrode 4 is formed. Then an opening 9 is formed in the insulating layer 3 using a mask of the masking material used in formation of the electroconductive film 4' or gate electrode 4. A sacrifice layer 10 is deposited on the gate electrode 4, and thereon a metal layer 11 having a high melting point is deposited to form an emitter electrode 5, and then the metal layer 11 and sacrifice layer 10 are removed, and the insulating layer 2 is subjected to etching so that a dimple 12 is produced.</p> |
