Studies of cold cathode for vacuum microelectronics

点击翻译按钮获取中文摘要

An electron tunneling emission cathode has the potential for high current density and pressure insensitive of emission current and is a flat cathode in contrast with a field emission cathod. Due to these advantages, the tunneling cathode is a powerful candidate as a fine cathode for vacuum microelectronic devices.We have fabricated an Al-gate and an amorphous Si-gate MOS electron tunneling cathodes and have examined the emission characteristics. The emission current was given by the Fowler and Nordheim equation and the transfer ratio, i.e., the ratio of the emission current to the total current flowing through the MOS diode was 0.7%. The emission current was very stable in the Si-gate MOS cathode, in contrast with the Al-gate cathode. In addition, the current was nearly independent of pressure ranging from 10^<-8> to 10^<-1> Torr.Energy distribution of emitted electrons were measured by a high resolution electron energy analyzier developed in this study. It became clear that the emission characteristics of the MOS electron tunneling cathode were mainly determined by scattering process of hot electrons in the conduction band of the oxide in MOS cathode. Following the experimental results, a new structure of tunneling cathode constructed with 4 thin layrs was proposed to improve emission characteristics of an electron tunneling cathode.