Hafnium nitride field emitter array for field emission amplifier

A field emitter array (FEA) is expected for operation under a server environment. We focused on hafnium nitride (HfN) for the cold cathode metal, because it possesses relative lower work function [1] and high resistance against oxidation at high temperature [2]. We have already reported fabrication of HfN-FEA and emission properties of HfN-FEA at high temperature [3], but we have not examined HfN-FEA as an active device. In this study, we evaluated HfN-FEA with the three constants of an electronic device, i.e. transconsductance (gm), collector resistance (rc), voltage amplification factor (mu).