Pulsed laser-deposited nanocrystalline GdB6 thin films on W and Re as field emitters
| Title | Pulsed laser-deposited nanocrystalline GdB6 thin films on W and Re as field emitters |
| Publication Type | Journal Article |
| Year of Publication | 2016 |
| Authors | Suryawanshi, SR, Singh, AK, Phase, DM, Late, DJ, Sinha, S, More, MA |
| Journal | Applied Physics A-Materials Science & Processing |
| Volume | 122 |
| Issue | 10 |
| Pagination | Article Number: 899 |
| Date Published | OCT |
| Abstract | Gadolinium hexaboride (GdB6) nanocrystalline thin films were grown on tungsten (W), rhenium (Re) tips and foil substrates using optimized pulsed laser deposition (PLD) technique. The X-ray diffraction analysis reveals formation of pure, crystalline cubic phase of GdB6 on W and Re substrates, under the prevailing PLD conditions. The field emission (FE) studies of GdB6/W and GdB6/Re emitters were performed in a planar diode configuration at the base pressure similar to 10(-8) mbar. The GdB6/W and GdB6/Re tip emitters deliver high emission current densities of similar to 1.4 and 0.811 mA/cm(2) at an applied field of similar to 6.0 and 7.0 V/mu m, respectively. The Fowler-Nordheim (F-N) plots were found to be nearly linear showing metallic nature of the emitters. The noticeably high values of field enhancement factor (beta) estimated using the slopes of the F-N plots indicate that the PLD GdB6 coating on Wand Re substrates comprises of high-aspect-ratio nanostructures. Interestingly, the GdB6/W and GdB6/Re planar emitters exhibit excellent current stability at the preset values over a long-term operation, as compared to the tip emitters. Furthermore, the values of workfunction of the GdB6/W and GdB6/Re emitters, experimentally measured using ultraviolet photoelectron spectroscopy, are found to be same, similar to 1.6 +/- 0.1 eV. Despite possessing same workfunction value, the FE characteristics of the GdB6/W emitter are markedly different from that of GdB6/Re emitter, which can be attributed to the growth of GdB6 films on W and Re substrates. |
| DOI | 10.1007/s00339-016-0423-y |
| Type of Journal (Indian or Foreign) | Foreign |
| Impact Factor (IF) | 1.444 |
Divison category:
Physical and Materials Chemistry
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