| 摘要 |
<p>PURPOSE:To facilitate the control of an emitted electron flow and make it possible to reduce an electron emission area and perform integration, by providing an N channel region in the surface of at least a part of a P type semiconductor substrate, and providing a means for emitting electrons from the exposed portion of the substrate. CONSTITUTION:A source 2 of a high-concentration N type region for implanting electrons and an insulator layer 3 made of SiO2 or the like and having a thickness of 0.1mum are provided at one end of a P-Si substrate 1. An Al film, which becomes metal layers as gate electrodes G1.4 and G2.5, is provided. When a positive voltage of 5V or the like is applied to the gate electrode G1.4, an N channel 7 is produced on the boundary between the insulator layer 3 and the semiconductor substrate 1. When a high positive voltage of 10V or the like is applied to the gate electrode G2.5 in addition to the application of the positive voltage of 5V or the like, a potential well right under the gate electrode G2.5 is deepened to accelerate electrons in the N channel 7 so that the electrons reach a semiconductor surface 6 and are emitted into a vacuum. As a result, an electron flow 9 can be generated by applying an accelerating voltage to an anode 8.</p> |
