title: Highly reliable field electron emitters produced from reproducible damage-free carbon nanotube composite pastes with optimal inorganic fillers.
abstract: Highly reliable field electron emitters were developed using a formulation for reproducible damage-free carbon nanotube (CNT) composite pastes with optimal inorganic fillers and a ball-milling method. We carefully controlled the ball-milling sequence and time to avoid any damage to the CNTs, which incorporated fillers that were fully dispersed as paste constituents. The field electron emitters fabricated by printing the CNT pastes were found to exhibit almost perfect adhesion of the CNT emitters to the cathode, along with good uniformity and reproducibility. A high field enhancement factor of around 10,000 was achieved from the CNT field emitters developed. By selecting nano-sized metal alloys and oxides and using the same formulation sequence, we also developed reliable field emitters that could survive high-temperature post processing. These field emitters had high durability to post vacuum annealing at 950 °C, guaranteeing survival of the brazing process used in the sealing of field emission x-ray tubes. We evaluated the field emitters in a triode configuration in the harsh environment of a tiny vacuum-sealed vessel and observed very reliable operation for 30 h at a high current density of 350 mA cm(-2). The CNT pastes and related field emitters that were developed could be usefully applied in reliable field emission devices.
authors.affiliation: School of Advanced Device Engineering, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350, Korea. Nano Electron-source Creative Research Center, Electronics and Telecommunications Research Institute, 218 Gajeong-ro, Yuseong-gu, Daejeon 305-700, Korea.
authors.forename: Jae-Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Jeong
authors.forename: Jun-Tae
authors.initials: JT
authors.lastname: Kang
authors.forename: Sungyoul
authors.initials: S
authors.lastname: Choi
authors.forename: Seungjoon
authors.initials: S
authors.lastname: Ahn
authors.forename: Yoon-Ho
authors.initials: YH
authors.lastname: Song
mesh_terms: D003952:Diagnostic Imaging / Q000295:instrumentation*; D004566:Electrodes; D004583:Electrons; D004867:Equipment Design; D008422:Materials Testing; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman; D013696:Temperature; D014965:X-Rays
chemical_list: D037742:Nanotubes, Carbon