Field Emitter Failure Mechanisms and Harsh Environment Robustness Studies

Abstract

Modern day field emitters can fail due to several mechanisms that are not well understood. This paper presents experiments that aim to identify the mechanisms behind failure. Two types of devices, Silicon gated field emitter arrays (SiGFEAs) and Titanium Silicon Oxy Nitride (TiSiON) lateral field emitter devices were characterized experimentally. Si-GFEAs were tested for arc occurrence time for a fixed gate voltage of 50 V and a fixed collector voltage of 200 V. The emitter was grounded. Initial results from the temporal response experiment show that the emitter experiences arcing first. However, future experiments will provide an accurate identification of the arc initiating electrode. For the planar device, a diode was chosen and IV characterization was performed at 50 °C and 400 °C. Experiments showed that for an applied collector voltage of 10 V, the field emission current was ≈ 5.5 nA before the heat treatment and was ≈ 2.75 nA after the 400 °C heat treatment. This reduction in current could be attributed to the removal of water vapor by heat treatment resulting in the reduction in the surface leakage current.