Fabrication and emission properties of LaB 6 field emission microtriodes

Abstract

Lanthanum hexaboride(LaB 6 ) is a new and exciting field emitter material due to its special properties. In this paper, LaB 6 field emission microtriodes have been fabricated on n-type(100) single crystal silicon substrates by Spindt method.Such cathodes are produced in closely packed arrays containing 2.7×10 4 cones that are about 1.0 m μ tall in an area of 1mm 2 . The field emission characteristics are studied in a conventional triode test cell in vacuum system. The turn-on voltage of LaB 6 -FEAs is 60V, and the emitters draw about 5.58mA total emission at the gate voltage of 145V. Furthermore, the Fower-Nordheim plot obtained from the current-voltage characteristic is found to be nearly linear in accordance with the quantum mechanical tunneling phenomenon.

The Growth Methods and Field Emission Studies of Low-Dimensional Boron-Based Nanostructures

“…In present studies, the emission current of nearly all individual boron-based nanostructures can arrive at 1 µA current and their maximum current can be even as high as 96.0 µA in measurements [23,24,28,86]. But when their nanostructured film are used, the averaged emission current of a single nanostructure on film is found to be only about 0.2 µA [33], which is far lower than that of individual nanostructure. As a result, the FE performances of LD boron-based nanostructures are not good enough for their cold cathode electron source applications nowadays.…”

“…As presented in Figure 3d. X. J. Wang et al [33,34] respectively prepared the LaB 6 FE arrays and microtriodes by etching the LaB 6 single crystal or micro-fabrication technology. Single crystalline boron NTs with β-rhombohedral structure can be fabricated in a Cu alloy at 1573 K and separated by 50% HNO 3 solution [82].…”

“…It is found that the SmB6 NWs have a lower turn-on field (6.5 V/μm) than SmB6 NPs (6.9 V/μm), and the maximum emission current density of both nanostructures can reach several hundred μA/cm 2 . As seen in Figure 6(d), X. J. Wang et al [33,34] found that the emission current density of LaB6 FE microtriode arrays can arrive as high as 558 mA/cm 2 at the gate voltage of 145 V. By using a flat metal stage as anode, we [28] investigated the FE properties of LaB6 NWs film with an area of 0.34 cm 2 . It is seen in Figure 6c,d, the FE current density of LaB6 NW film arrives at 16.7 mA/cm 2 and their current fluctuation is only about 1.7% for 2 hour continuous measurements.…”

“…Among numerous LD nanostructure candidates, boron-based nanostructures are believed as ideal cold cathode nanomaterials [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] because they not only can meet the above requirements for FE current. For example, boron monoelement nanotube (NT) structures [24] have been proven to have metallic conductivity whether their chirality belongs to armchair or zigzag, which are very beneficial for actual FE applications.…”