DOPING OF POLYCRYSTALLINE DIAMOND BY BORON ION-IMPLANTATION

Polycrystalline diamond films, heavily implanted with boron ions (2 X 10(16) cm-2, 60 keV) are found to exhibit, following annealing and gra phite removal, electrical properties similar to those obtained for che mical vapor deposited diamond, heavily doped with B during film growth . Control experiments in which carbon ions were implanted and annealed under identical conditions did not show any significant electrical co nductivity, verifying that the measured effects are caused by chemical doping due to the presence of B. It is therefore concluded that dopin g of polycrystalline diamond by ion implantation is possible and graph itization along grain boundaries, that one might have expected to occu r as a result of implantation and annealing, does not seem to severely affect the electrical properties of the implantation-doped material.