Robust CNT-PVP Field-Effect Electron Source for Application in Vacuum Mems Structures

This article presents a field electron emitter dedicated for MEMS applications, based on a composite of carbon nanotubes (CNTs) and cross-linked polyvinyl-pyrrolidone (PVP), fabricated using a thermomechanical pulling method. The resulting needle-like structure has a strong CNT adhesion to the silicon substrate and enables efficient field emission with a low threshold voltage (~300 V), high current output (up to 2000 μA at 2000 V), and very good long-term stability. The composite combines the conductivity and strength of CNTs with the thermal resistance and adhesion of cross-linked PVP, maintaining good emission performance even after high-temperature processes such as anodic bonding. A multitip architecture increases total emission and provides redundancy, though it may introduce beam inhomogeneity, which can be improved via electrostatic and magnetic focusing. The robustness and compatibility with MEMS fabrication make it a promising solution for miniaturized X-ray sources and vacuum microelectronic devices.