ELECTRON-EMMITING SEMICONDUCTOR DEVICE

摘要

21 An electron source having a rapid response time comprises at least on n-p-n structure (and possibly an array of said n-p-n structure) formed in a silicon or other semiconductor body (10) by a p-type first region (1) between n-type second and third regions ( 2 and 3). Electrons (24) are generated in the n-p-n structure (2,1, 3) for emission into free space (20) from a surface area (4) of the body (10) after flowing from the second region (2) through the first and third regions (1 and 3). The n-p-n structure (2, 1, 3) has electrode connections (12 and 13) only to the n-type second and third regions (2 and 3). The first region (1) provides a barrier region restricting the flow of electrons from the second region (2) to the third region (3) until a sufficient potential difference is applied between the electrode connections (12 and 13) to bias the third region (3) positive with respect to the second region (2) and to establish a supply of hot electrons (24) injected into the third region (3) with sufficient energy to overcome the electron work function between the surface area (4) and free space (20). The barrier region (1) forms depletion layers with both the n-type second and third regions (2 and 3) and is depleted by the merging together of these depletion layers when the potential difference is applied to establish said supply of hot electrons (24).