Boron electrical properties

Elements dissolved in boron influence its crystal structure. Dissolved impurities also influenee the physical and chemical properties of boron, especially the electrical properties, because boron is a semiconductor. Preparation of solid solutions in jS-rh boron requires a careful choice of crucible material. To avoid contamination, boron nitride or a cold, coinage-metal crucible should be used or the levitation or floating-zone melting techniques applied. 

Thermal Evaporation The easiest way of evaporating metal is by means of resistance evaporators known commonly as boats . Boats, made of sintered ceramics, are positioned side by side at a distance of approximately 10 cm across the web width (Fig. 8.1). Titanium boride TiB2 is used as an electrically conductive material with boron nitride BN (two-component evaporator) or BN and aluminum nitride AIN (three-component evaporator) as an insulating material [2]. By combination of conductive and insulating materials, the electrical properties of evaporators are adjusted. 

Wilson NR, Clewes SL, Newton ME, Unwin PR, Macpherson JV (2006) Impact of grain-dependent boron uptake on the electrochemical and electrical properties of polycrystalline boron doped diamond electrodes. J Phys Chem B 110 5639-5646... 

LP-CVD ZnO The variation of the electrical properties for a boron-doped LP-CVD ZnO film in dependence on its thickness d is presented in Fig. 6.15. The electrical properties are resistivity p, carrier density N, and mobility p. 

The following paragraph discusses the particular case of boron-doped LP-CVD ZnO developed at IMT Neuchatel, for which DEZ and H2O are used as growth precursors. It describes in more detail the structural, optical, and electrical properties of the resulting ZnO films when the gas flow ratio H2O/DEZ is varied. 

Figures 6.37 and 6.38 show the variation of electrical properties as a function of the dopant content of ZnO films. Figure 6.37 shows the case of AP-CVD ZnO F with fluorine as dopant (here, the fluorine atomic fraction is considered as dopant content). Figure 6.38 shows the case of LP-CVD ZnO B with boron as dopant (here, the B2H6/DEZ ratio is considered as dopant content). The electrical properties taken into consideration are the conductivity a, the resistivity p, the mobility //, and the free carrier density N.

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... 

Generally speaking most of the shallow impurity levels which we shall encounter are based on substitution by an impurity atom for one of the host atoms. An atom must also occupy an interstitial site to be a shallow impurity. In fact, interstitial lithium in silicon has been reported to act as a shallow donor level. All of the impurities associated with shallow impurity levels are not always located at the substitutional sites, but a part of the impurities are at interstitial sites. Indeed, about 90% of group-VA elements and boron implanted into Si almost certainly take up substitutional sites i.e., they replace atoms of the host lattice, but the remaining atoms of 10% are at interstitial sites. About 30% of the implanted atoms of group-IIIA elements except boron are located at either a substitutional site or an interstitial site, and the other 40% atoms exist at unspecified sites in Si [3]. The location of the impurity atoms in the semiconductors substitutional, interstitial, or other site, is a matter of considerable concern to us, because the electric property depends on whether they are at the substitutional, interstitial, or other sites. The number of possible impurity configurations is doubled when we consider even substitutional impurities in a compound semiconductor such as ZnO and gallium arsenide instead of an elemental semiconductor such as Si [4],... 

F. Morin and J. F. Maita, Electrical properties of silicon containing arsenic and boron, Phys. Rev. 96 28-35 (1954). 

Deguchi, M., Kitabatake, M. and Hirao, T. (1996), Electrical properties of boron-doped diamond films prepared by microwave plasma chemical vapour deposition. Thin Solid Films,... 

Because ion-beam treatment effect on the electrical properties of the wafers is independent of the treatment temperature and ion type, one of the mechanisms of this influence is the formation of point defects. This can lead to (i) the positive charge creation in the surface oxide layer [2] (ii) transfer of boron atoms into the electrically inactive interstitial positions by the ion-beam generated Sii atoms... 

Previous Work on Latent Catalysts for Epoxy Resins. Numerous patents (, , ) have been issued in recent years on the development of latent catalysts for DGEBA (i.e., diglycidylether of bisphenol a ) resins, but most fulfill only a few of the conditions outlined above. One of the most successful of these has been the boron trifluoride-monoethylamine complex ( ). However, one of the serious disadvantages of this particular latent catalyst is the poor electrical properties at elevated temperatures of the epoxy resin in the cured state (7 ). 

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