Basic Research on Vacuum Breakdown and Field Emission Characteristics on SUS304 Electrode with Micro-sized Pits

• Published in: E-journal of surface science and nanotechnology Vol. 22; no. 3
• Main Authors: Hishikawa, Kohei, Yamano, Yasushi
• Format: Journal Article
• Language: English; Japanese
• Published: Tokyo Japan Science and Technology Agency 01.01.2024
• Subjects: Apertures; Breakdown; Chemical polishing; Electric field strength; Electric fields; Electric strength; Electrodes; Electron emission; Emission analysis; Field emission; Pits
• ISSN: 1348-0391
• DOI: 10.1380/ejssnt.2024-015

In recent years, vacuum has attracted attention as an excellent insulating medium and is used in many high voltage and high electric field equipment. To improve the performance and reliability of the equipment, it is essential to improve the electric strength, and more advanced insulation technology is required. In a previous study, it was reported that apertures and the number of apertures affected the property of electron emission on electrodes with millimeter-sized apertures. Besides, micro-sized pits have been observed on electrode surface after chemical polishing and electric breakdown. However, it is not clear that how these micro-sized pits affect electron emission, whether they cause vacuum breakdown, or not. Therefore, the purpose of this study was to investigate the effect of micro-sized pits on electron emission. In this study, voltage-current measurement, and breakdown tests were conducted in vacuum using electrodes with and without micro-sized pits (5 µm square side). In addition, electric field simulations of electrodes with micro- or millimeter-sized pit were performed. From these results, it is considered that micro-sized pits have little effect on field electron emission and it is suggested that the micro-sized pits appeared after breakdown are probably generated by other physical processes following the breakdown.