Lattice substitution of phosphorous in diamond by Mev ion implantation and pulsed laser annealing

Abstract

The difficulty of n-type doping of diamond is a well-known problem. In this work, we report a scheme to achieve over 40% lattice substitution of phosphorous (a potential n-type dopant) on diamond lattice sites by MeV P ion implantation. When followed by pulsed laser annealing using a laser beam focused to 15 μm in diameter, this scheme results in a doped layer buried about 1 μm below the surface. Analysis of the doped annealed region was accomplished by the use of a nuclear microprobe system, which allowed backscattering spectrometry and particle induced X-ray emission (PIXE), with ion channeling, to be applied to the laser annealed zones of the diamond. The analysis indicated that, remarkably, laser pulses of only tens of ns in duration are sufficient for annealing the radiation damage and forcing about half the implanted P onto the lattice sites, where they are expected to be electrically active donors.