Optimization of transistor structure for transistor-stabilized field emitter arrays

Reliability of the metal-oxide-semiconductor field-effect transistor (MOSFET)-stabilized field emitters at high-field operation has been assessed by comparing two different MOSFET structures. Electrical characteristics and behavior of carriers in the device structure have been investigated by means of device simulation. One structure, which is referred to as the externally connected-MOSFET emitter, exhibits an anomalous increase in drain current, which is induced by impact ionization at the drain edge. Upon evaluating the emission characteristics, it was clarified that the anomalous current increase induced by the impact ionization degraded stability and controllability of the emission current significantly. The other structure, which is referred to as the MOSFET-structured emitter, shows higher reliability with negligible effect of impact ionization.