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Nitrogen doping in purely sp 2 bonded forms of carbon
| Content Provider | Semantic Scholar |
|---|---|
| Author | Jungnickel, Gotthard Sitch, P. K. Frauenheim, Th. Eggen, Berry Heggie, M. I. |
| Abstract | We postulate wide-band-gap forms of carbon that locally have a planar bonding configuration as in graphite and, in contrast to diamond, are promising candidates for n-type doping by nitrogen. The presence of localized bonds makes them as stable as fullerene C 60 and causes large band gaps of Ϸ3 eV to appear. The allotropes accept both nitrogen and boron as substitutional dopants, making them potentially extremely useful for high-power, high-temperature, and high-speed device applications. ͓S0163-1829͑98͒51002-8͔ Potentially, carbon based semiconductor devices are very exciting. They should naturally lend themselves to effective heat management. Short and stiff carbon-carbon bonds combined with the lightness of the carbon atoms make diamond the best thermal conductor known. The strength of the CC bonds and the size of the electronic band gap ͑5.5 eV͒ make it very stable against degradation by temperature. Electronic transport is uniquely good for diamond: not only has it a large band gap but also the saturation velocity for electrons is very high. 1,2 Diamond has been at the center of an intense and highly successful research effort to grow it by chemical vapor deposition ͑CVD͒ in a region of the carbon phase diagram where it is technically unstable with respect to graphite. The conjunction of these factors might have been expected to lead to a generation of exceptional high power devices based on diamond. The reality at this time is somewhat different. Diamond can be doped by boron ͑as a sub-stitutional impurity͒ to give p-type material but cannot be doped by nitrogen to give n-type material. Nitrogen moves off the normal diamond lattice site, becoming threefold coordinated and leaving a level deep in the gap coming from the bond left dangling on the neighboring carbon atom. 4–7 Nitrogen has been found to preferably aggregate and to trap vacancies 8 in this way being a source of charge which, however , is captured at the vacancy. The difference in size between the carbon atoms and almost all other elements reduces their solubility in diamond to near zero. Phosphorus has been used to create n-type material using the cold implantation rapid annealing method 9 and by adding it to the CVD plasma. 10 The observed electrical activity is much less than would be expected from the P concentration, the doping efficiency is low, and films are reported to be highly resistive. 10 This may be due to a phosphorus-vacancy complex 11 that … |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://epubs.surrey.ac.uk/763795/1/jungnickel-PRB-57-R661.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Aggregate data Arabic numeral 0 Boron Carbon Dioxide Cardiovascular Diseases Chemical vapor deposition Control theory Departure - action Diamond Dopant Doping (semiconductor) Doping in Sports Elegant degradation Fullerenes Ion implantation Natural graphite Nitrogen Phase diagram Phosphorus Plasma Active Power semiconductor device Pyschological Bonding Simulated annealing Unstable Medical Device Problem Vacuum deposition Velocity (software development) electrical activity |
| Content Type | Text |
| Resource Type | Article |
