On the photo-electric emission aspect and on the electronic tube null

摘要

PROBLEM TO BE SOLVED: To provide a higher sensitive photoelectric emission surface having an active layer dissolving crystal defects and an electronic tube having the photoelectric emission surface. SOLUTION: On the photoelectron emission surface, an epitaxial layer formed by laminating a window layer 31 consisting of (Aly Ga1-y )x 'In1-x P and an active layer 32 consisting of Gax In1-x P in that order is closely provided through an antireflection film 20 on a glass face plate 10. A very thin surface layer 33 consisting of Cs2 O and an electrode 40 consisting of Cr and formed on the upper surface of the active layer 32 at the central part and the peripheral edge part. Crystal defects are dissolved in the active layer 32 in a range of an atomic composition ratio x of 0x=0.75, almost equal to the atomic composition ratio X' of the window layer, lengthening the diffusion length of a photoelectron generated by directing light to be detected, an object for detection, in the active layer 32. Thus, the photoelectric emission surface comes to higher sensitivity rather than conventional sensitivity. An electronic tube using the photoelectric emission surface detects weaker light rather than conventional light.