Electronic field emission

Fig. 2. Behavior of electron-field emission at room temperature from Spindt-type arrays of 5000 tips per mm, beginning and ending with ultrahigh vacuum (UHV), eg, ultracontrol (UC) (a) water (b) hydrogen and (c) oxygen, where the dashed line indicates noise. To convert Pa to torr, divide by 133.3.

Despite such limitations, plasma-deposited a-C(N) H films were found to be used in a number of applications. The stress reduction induced by nitrogen incorporation [12] and consequent adhesion improvement, allowed the development of a-C(N) H antireflective coatings for Ge-based infrared detectors [13]. It was also found that N can electronically dope a-C H films, and can strongly decrease the defect density, which gives prospects on its use as a semiconductor material [14]. Nitrogen incorporation was also found to decrease the threshold electric field in electron-field emission process [15], making possible the use of a-C(N) H films as an overcoat on emission tips in flat-panel display devices [16]. 

Electron exchange reactions, 13 445-447 Electron field emission, 17 49-50 Electron guns, 24 102 Electron-hole pairs... 

Applications of CNTs based on their electrical properties strongly depend on the diameter and helicity as well as parity.2 3 Doping of CNTs by boron and nitrogen renders them p-type and retype, respectively. MWNTs and SWNTs doped with nitrogen 4 17 and boron"1 9 have been reported. Boron-doped carbon nanotubes appear to exhibit enhanced electron field emission due to the presence of the boron atom at the nanotube edges.20 2 N-doped CNTs show retype behavior regardless of tube chirality.22... 

CASTRO ETAL. Scanning Electron Field Emission Microscopy... 

Buldum, A. and Lu, J.P., Electron field emission properties of closed carbon nanombes, Phys. Rev. Lett. 91 (23), 236801, 2003. 

The electron field emission photograph of a tungsten point formed by field evaporation at low temperatures, shown in Fig. 58, is dominated by the extensive nonemitting (110) plane. The emission comes primarily from the higher index planes around the 100 s with a much smaller contribution from the triangular llljs. The 100 poles, as well as the (211 s, are only ill defined. This is in contrast to the usual thermally shaped emitters, in which the 100, as well as 211 poles appear as definite and prominent areas of low emission. 

Electronically, the carbon nanotubes can have either metallic or semiconducting properties depending upon their chirality and diameter. The electronic gap is also controllable within a range of 0-l eV. This gives rise to possible metal-semiconductor or semiconductor-semiconductor junctions for use in nanoelectronic devices. The possibility of integrating carbon nanotubes into logic circuits was demonstrated in 2001. Another property of CNTs, the ability of electron field emission, has reached technological relevance. 

In reality, however, the electron field emission makes a significant contribution already at electric fields about 3 10 V/cm because of the field enhancement at the microscopic protrusions on metal surfaces. 

CNTs find applications in the areas such as micro electronics, field emission displays. X-ray sources and gas sensors. Single waUed and multi-waUed CNTs can be grown using high pressure arcs, laser ablation and chemical vapour deposition. 

Kiittel OM, Groening O, Emmenegger C, Schlapbach L. Electron field emission from phase pure nanotube films grown in a methane/hydrogen plasma. Appl Phys Lett 1998 73 2113-5. 

TalinAAjFelterTE, Friedmann TA, Sullivan JP, SiegalMP. Electron field emission from amorphons tetrahedrally bonded carbon films. J Vac Sci Technol A 1996 14 1719-22. 

Robertson J. Mechanisms of electron field emission from diamond, diamond-like carbon, and nanostructured carbon. J Vac Sci Technol B 1999 17 659-65. 

Cole MT, Li C, Zhang Y, Shivareddy SG, Barnard JS, Lei W, et al. Hot electron field emission via individnally transistor-ballasted carbon nanotube arrays. ACS Nano 2012 6 3236-12. 

CNTs possess interesting physical properties. Thermal conductivity of CNTs is in excess of2000 w/m/K. They have unique electronic properties. Applications include electromagnetic shielding, electron field emission displays for computers and other high-tech devices, photovoltaics, super capacitors, batteries, fuel cells, computer manory, carbon electrodes, carbon foams, actuators, material for hydrogen storage, and adsorbents. 

Wang MS, Peng LM, Wang JY, Chen Q (2005) Electron field emission characteristics and field evaporation of a single carbon nanotube. J Phys Chem B 109 110... 

Eield emission (EE) (also known as field electron emission or electron field emission) is the emission of electrons from a solid surface into vacuum induced by an electrostatic field. FE was first explained by quantum tunneling of electrons in the late 1920s [1], and the theory of FE from bulk metals was proposed by Fowler and Nordheim [2]. A family of approximate equations, called Fowler-Nordheim equations (F-N equations), are named in their honor and have been shown in terms of experimentally measured quantities as... 

Wang MS, Wang JY, Peng LM, Engineering the cap structure of individual carbon nanotubes and corresponding electron field emission characteristics. Applied Physics Letters, 2006. 88(24) 243108. 

Charlier JC, Teirones M. et al.. Enhanced electron field emission in B-doped carbon nanotubes. Nano Letters, 2002. 2(11) 1191-1195. 

FIGURE 10.15 (a) Electron field emission characteristics for an onion-like graphitic-particle film and an... 

With a view to studying high field conduction in liquids, the point-to-plane geometry has been widely employed. The pioneering work on the subject by Halpern and Comer (1969) has highlighted the importance of electronic-field emission at the cathode, and liquid-field ionization at the anode. Some common features characterize high field DC conduction ... 

Y. Tzeng, C. Liu, A. Hirata, Effects of oxygen and hydrogen on electron field emission Irom microwave plasma chemically vapor deposited microcrystalline diamond, nanocrystalline diamond, and glassy carbon coatings. Diam. Relat. Mat. 12(3-7), 456-463 (2003)... 

Vu Thien Binh, N Garcia, ST Purcell. Electron field emission from atom-sources Fabrication, properties, and applications of nanotips. Adv Imaging Electron Phys 95 63, 1996. 

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