Emission property and current fluctuation of starlike thin-film field emitter array with self-feedback function

Abstract

An advanced thin-film field emitter array (FEA) with self-feedback function which suppresses the fluctuation of emission current was fabricated by self-aligned processing. Each starlike miniature field emitter in the FEA has a double layer of a resistive and an electron emitting layer. 200-μm-square FEAs of Mo or W emitters, both had a threshold voltage of about 50 V, emitted the current of 4 μA at a gate voltage of 90 V. The emission current of a 5-mm-sq FEA was 300 μA at 85 V. Insertion of the resistive layer with 2.4 MΩ worked to stabilize the current fluctuations, but insufficient for practical applications. However, it was found that the resistive value should be above 50 MΩ to suppress the emission current fluctuations less than 5%. It is confirmed that the electron emission in a 5-mm-sq FEA was stably continued during ∼1200 h.