Field Emission from Self-Catalyzed GaAs Nanowires

Abstract

We report observations of field emission from self-catalyzed GaAs nanowires grown on Si (111). The measurements were taken inside a scanning electron microscope chamber with a nano-controlled tungsten tip functioning as anode. Experimental data were analyzed in the framework of the Fowler-Nordheim theory. We demonstrate stable current up to 10−7 A emitted from the tip of single nanowire, with a field enhancement factor β of up to 112 at anode-cathode distance d = 350 nm. A linear dependence of β on the anode-cathode distance was found. We also show that the presence of a Ga catalyst droplet suppresses the emission of current from the nanowire tip. This allowed for the detection of field emission from the nanowire sidewalls, which occurred with a reduced field enhancement factor and stability. This study further extends GaAs technology to vacuum electronics applications.

Transport and Field Emission Properties of MoS2 Bilayers

“…For [ 45 ]. The obtained mobility, , is on the low side of the range typically reported for uncovered — to [ 8 , 33 , 46 , 47 ]. Our value for the field-effect mobility could be slightly underestimated because it does not exclude the effect of the contact resistances [ 48 ], which increase the total resistance of the sample and the probability of electron scattering.…”

“…Nanostructures, such as nanoparticles [ 24 , 25 ], nanowires [ 26 ], and nanotubes [ 23 , 27 , 28 , 29 , 30 ] or 2D materials [ 31 , 32 ], for their intrinsically sharp edges and high aspect ratio, are natural field emission sources. Indeed, semiconducting or metallic nanostructured materials have been considered for FE applications in vacuum electronics [ 33 ], flat panel displays [ 34 ], electron microscopy [ 35 ], X-ray tubes [ 36 , 37 ], etc.…”

Nanotip Contacts for Electric Transport and Field Emission Characterization of Ultrathin MoS2 Flakes

“…For a flat cathode, FE is enabled by a strong electric field (several kV/µm), while if the cathode surface has sharp edges or protrusions, electrons may be extracted by a considerably lower applied electric field, since the physical geometry provides a field enhancement near the emitting surface. To date, several nanostructures have been investigated as possible field emitters, like metallic nanowires and nanoparticles [26][27][28], semiconducting nanowires and nanoparticles [29][30][31][32][33], nanodiamonds [34], carbon nanostructures [35], carbon nanotubes (CNTs) [36][37][38][39][40][41], and graphene [33,[42][43][44]. Instead, few studies have investigated FE from MoS 2 structures, such as sheets and nanosheets [45,46], nanotubes and nanoflowers [47,48], nanostructures [49], thin films [50], and bilayers [12].…”

Field emission from carbon nanotube fibers in varying anode-cathode gap with the consideration of contact resistance

“…Note that some of the previous studies (Ref. 28 and reference therein) also reported a growing field enhancement factor with increasing AK distance for self-catalyzed GaAs nanowires. The complicated dependence of the field enhancement factor with AK distance might therefore be the result of two competing effects: geometrical effects and material effects.…”