Investigation of field emission characteristics for Si-base materials: Titanium silicide, poly-Si, and single crystal Si

We have fabricated poly-Si, Si, and Ti silicide field emitter arrays employing in situ vacuum encapsulated lateral field emitter structures and investigated the field emission characteristics such as turn-on voltage, emission current density, and the stability of the emission current. Although poly-Si and Si emitters have almost identical turn-on voltages, Si emitters have a sharper turn on than poly-Si emitters due to their uniform surface. The current densities of poly-Si and Si emitters are 0.47 and 0.43 μ A/tip, respectively, at an anode to cathode voltage of 90 V. The turn-on voltage and current density of Ti silicide emitters are about 31 V and 1.81 μ A/tip at VAK of 90 V. The data of the normalized current fluctuations indicate that the Ti silicide emitters have the most stable current. The experimental results show that Ti silicide is the most promising among these three materials due to its low work function, uniform surface, and stable characteristics.