• Title/Summary/Keyword: field emission properties

Search Result 864, Processing Time 0.038 seconds

Field Emission Characteristics of ZnO Nanowires Grown by Hydrothermal Method (수열합성법에 의해 성장된 ZnO 나노와이어의 전계방출 특성)

  • No, Im-Jun;Kim, Sung-Hyun;Shin, Paik-Kyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.24 no.2
    • /
    • pp.101-105
    • /
    • 2010
  • We fabricated FEDs(Filed emission devices) based on ZnO nanowires. The ZnO nanowires were synthesized on Au thin films by hydrothermal method at the temperature of 90[$^{\circ}C$] on hot plate. In order to form tips of the ZnO nanowire, SDS(Sodium Dodecyl Sulfate) was mixed in O.05-0.3[wt%] solution as capping material. After 2 hour growth, we obtained nanowires of chain form The high-purity nanowires showed sharp tip geometry with a wurtzite structure. The field emission properties of the ZnO nanowires were investigated in high vacuum chamber. The turn-on field for the ZnO nanowires was found to be about 4.1[V/${\mu}m$] at a current density of 0.1[${\mu}A/cm^2$].

Electric properties of DLC Emitter (DLC Emitter 전기적 특성)

  • Lee, Sang-Heon
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1312_1313
    • /
    • 2009
  • In this study the fabrication technique of the planner field emission device structure with a DLC layer were studied. The bottom Mo electrode using electrochemical method on the DLC layer deposited using assist sputtering.

  • PDF

Electronic Spectroscopy and Ligand Field Analysis of cis-$>[Cr(cycb)Cl_2]$Cl

  • Choi, Jong-Ha;Oh, In-Gyung;Subodh Kumar;Ryoo, Keon-Sang
    • Journal of Photoscience
    • /
    • v.11 no.1
    • /
    • pp.19-23
    • /
    • 2004
  • The sharp-line absorption spectrum of microcrystalline samples of cis-[Cr(cycb)$Cl_2$]Cl (cycb=rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been measured between 13000 and $16000 cm^{-1}$ at temperatures down to 5K. The 77K emission and excitation spectra, and 298 K infrared and visible absorption spectra have also been measured. The nine electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using the observed transitions, a ligand field analysis has been performed to probe the ligand field properties of coordinated atoms in the title chromium(III) complex. The zero-phonon line in the sharp-line absorption spectrum splits into two components by $240 cm^{-1}$ , and the $large ^2$$_E{g}$ splitting can be reproduced by the modem ligand field theory. It is confirmed that nitrogen atoms of the macrocyclic cycb ligand have a strong $\sigma$-donor character, but chloride ligand has weak $\sigma$- nd $\pi$-donor properties toward chromium(III) ion.n.

  • PDF

OPTICAL SPECTROSCOPY AND LIGAND FIELD PARAMETERS OF CIS-DIBROMO(1,4,8,11-TETRAAZACYCLOTETRADECANE) CHROMIUM(III) BROMIDE

  • Choi, Jong-Ha
    • Journal of Photoscience
    • /
    • v.4 no.3
    • /
    • pp.121-125
    • /
    • 1997
  • The 77 K emission and excitation, and room-temperature visible spectra of cis[Cr(cyclam)Br$_2$]Br (cyclam=1,4,8,11-tetraazacyclotetradecane) are reported. The mid- and far-infrared spectra at room-temperature are also measured. The vibrational intervals of the electronic ground state are extracted from the far-infrared and emission spectra. The ten electronic bands due to spin-allowed and spin-forbidden transitions are assigned. It is found that nitrogen atoms of the cyclam ligand have strong $\sigma$-donor characters, but bromide ligand has weak $\sigma$- and $\pi$-donor properties toward chromium(III) ion. The zerophonon line in the excitation spectrum splits into two components by 172 cm$^{2-}$, and the large $^2E_g$ splitting can be reproduced by the ligand field theory.

  • PDF