Abstract: In an electron tube, an electrical resistance film having a stacked structure of electrically insulating layers and electrically conductive layers is formed on holding surfaces of bases in insulating substrates. This electrical resistance film is made as a firm and fine film with a desired resistance by use of an atomic layer deposition method, which can suppress electrification of the bases comprised of an insulating material. This makes it feasible to stably maintain withstand voltage characteristics.

Abstract: In an electron tube, an atomic layer deposition method is used to form an electrical resistance film having a stacked structure of electrically insulating layers and electrically conductive layers or a mixed structure of an electrically insulating material and an electrically conductive material, so as to cover the whole of an inner wall surface and an outer wall surface of a second envelope. By use of the atomic layer deposition method, the firm and fine electrical resistance film with a desired resistance can be formed on an insulation surface, without containing a material such as a binder. When the electrical resistance film is provided with slight electrical conductivity, it can suppress occurrence of withstand voltage failure due to electrification of the insulation surface or the like and realize stability of withstand voltage characteristics.

Abstract: The present invention aims at providing a photocathode which can improve various characteristics. In a photocathode 10, an intermediate layer 14, an underlayer 16, and a photoelectron emission layer 18 are formed in this order on a substrate 12. The photoelectron emission layer 18 contains Sb and Bi and functions to emit a photoelectron in response to light incident thereon. The photoelectron emission layer 18 contains 32 mol % or less of Bi relative to SbBi. This can dramatically improve the linearity at low temperatures.

Abstract: The present invention aims at providing a photocathode which can improve various characteristics. In a photocathode 10, an intermediate layer 14, an underlayer 16, and a photoelectron emission layer 18 are formed in this order on a substrate 12. The photoelectron emission layer 18 contains Sb and Bi and functions to emit a photoelectron in response to light incident thereon. The photoelectron emission layer 18 contains 32 mol % or less of Bi relative to SbBi. This can dramatically improve the linearity at low temperatures.