Accelerator based MeV ion implantation of Ca(2+) and P(2+) into the titanium substrate to form hydroxyapatite (HA) has been carried out. Calcium hydroxide was formed after heating the calcium implanted titanium in air at 80 degrees C for 3 h. Upon subsequent annealing for 5 min at 600 degrees C HA was formed on the surface. Penetration depth of the HA layer in this method is much higher as compared to key ion implantation. By elemental analysis, Ca/P ratio of the HA was found to be 1.76 which is higher than the ideal 1.67. This higher Ca/P ratio is attributed to the higher penetration depth of the MeV technique used. (C) 2009 Elsevier B.V. All rights reserved.