Effects of ion implantation doping on the formation of TiSi2

Abstract
Si samples implanted at various energies and with various doses of 75As+, 31P+, and 11B+ were evaluated for the formation of TiSi2 from Ti films (400 Å) deposited after a postimplant annealing. Experimental results suggested that implantation conditions strongly affect the formation of TiSi2 at temperatures of 570–700 °C and result in a wide range of sheet resistance values, especially in the case of 75As+ and 31P+ implantations. This is believed to be due to the differences in the extent of the TiSi2 formation reaction, which depends on dopant concentration and distribution. We found that, in order to form appreciable silicide and obtain low sheet resistances, the concentrations of As and P should be kept lower than the critical concentrations at the Ti/Si interface.