Electromechanical Reliability of Integrated Air-Bridge Anodes for Vacuum Microelectronic Devices

Abstract

Vacuum field-effect diodes (VFEDs) offer significant advantages in high-frequency and harsh-environment applications due to their superior radiation hardness and robustness when operating under high temperatures. In this study, electromechanical effects and packaging considerations of air-bridge-style VFEDs with integrated metal anodes suspended over metal nanotip emitters were numerically investigated. A key challenge in such designs is ensuring mechanical reliability and preventing electrostatic pull-in, leading to arcing and device failure. The impact of anode material, width, span, thickness, and the anode-to-cathode gap on device performance was investigated. The lookup table approach successfully integrated emission current predictions into the electromechanical model, enabling accurate estimates of emission current under various anode deflection conditions. These findings provide critical insights into optimizing VFED designs for enhanced reliability and performance.