Electrical Characterization of Boron-Implanted Diamond

摘要

Natural type Pi alpha(insulating) diamonds were implanted at liquid nitrogentemperature with either boron or carbon plus boron. Van der Pauw resistivity and Hall effect measurements as a function of temperature were used to determine the effect of the implantation in comparison with the unimplanted side of the sample. Implantation with carbon plus boron resulted in a carrier concentration more than an order of magnitude greater than that resulting from implantation with boron alone, but with a much lower hole mobility. Previous attempts to utilize ion implantation to introduce electrically active dopants into semiconducting diamond have yielded inconsistent results, primarily because the implantation produces a variety of damage mechanisms in the diamond lattice. In addition to the vacancy and interstitial defect centers common to other materials, diamond has an additional damage mechanism due to the transformation of the tetrahedrally bonded diamond lattice to a carbon lattice consisting of graphitic-type bonds. These graphitic layers may show electronic conduction similar to that of an n-type layer.