Enhanced extreme ultraviolet lighting using carbon nanotube-based cold cathode electron beam irradiation

Abstract

Laser-produced tin (Sn) plasma (LPP) is used to produce high-performance semiconductors using extreme ultraviolet (EUV), but LPP generates debris that limits the lifespan of the optical system, so research on debris mitigation is being conducted. When electrons are directly irradiated to a solid target, occurrence of debris can be minimized, and compact and low-cost EUV lighting can be manufactured. Here, we demonstrated enhanced EUV generation by optimizing the irradiation of Sn with electrons emitted from carbon nanotube-based cold cathode electron beam (C-beam). To minimize debris, a usable zone in which Sn does not melt was identified. It was demonstrated that using two C-beams in the usable zone increased the EUV intensity by about two times compared to using one C-beam. The multiple C-beam irradiation technique enables high-output EUV lighting by overlapping EUV light, which should be led by the development of advanced lithography and inspection technology.

Boosting the Electron Beam Transmittance of Field Emission Cathode Using a Self-Charging Gate

“…We believe that this high-efficiency, long-term stable cathode has great potential for using in neutralizers, solar sails and tethered satellites in the long-term space missions.Carbon nanotubes (CNTs) present numerous advantages as the field emission cathodes (FEC), such as its ultralow turn on voltage (>0.4 V/μm) 1, 2 resulting from the low work function (~5 eV), [3][4][5] exceptional chemical and physical stabilities, 6 as well as high electrical and thermal conductivity 7, 8 attributed to the C-C covalent bond, seamless hexagonal network architecture and one-dimension carbon nanostructures. 9, 10 These unique characteristics render FEC an ideal electron source for various applications, including field emission scanning electron microscopy (FESEM), 11 field emission display (FED), 12 electron-beam (E-beam) lithography (EBL) 13,14 and X-ray tube. 15 In modern space technologies, 16,17 FEC often severs as the cathode for electric propulsion (EP) system, providing electrons to neutralize the positive ions or positively charged droplets to avoid charging of the spacecraft.…”