PHOTOCATHODE

摘要

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.