A Stable Field-Emission Light Source With ZnO Nanoemitters

A field-emission cathode is fabricated with ZnO tetrapodlike nanoemitters. With a simple planar triode structure, a cathodoluminescent light source has been investigated. Because of the characteristics of surface-conduction electron-emission planar triode, this cathodoluminescent light source shows a very good performance. As experimental results show, the turn-on electric field is about 1 V/mum, whereas the current density is 1 muA/cm
²
. The threshold electric field is 1.6 V/mum, whereas the current density is 1 mA/cm
²
. When a pulse voltage with 4% duty cycle is applied on the gate electrode, the fluctuation of anode current is smaller than 15 % during 200 h.