Structure and properties of Ca-plasma-implanted titanium

Plasma immersion ion implantation and deposition (PIII-D) has been proven to be an effective approach to enhance the surface properties of various types of materials and applied in many industrial areas, such as semiconductor and biomaterials. In this work, calcium ions were implanted into and deposited onto titanium using PIII-D to improve its surface bioactivity. Based on secondary ion mass spectrometry (SIMS) results, the Ca implantation depth increases with higher bias voltages. After exposure to air, the outermost surface is found to comprise calcium hydroxide and calcium carbonate. The bioactivity of the implanted titanium was evaluated using a simulated body fluid (SBF) soaking test. After the sample was soaked in the simulated body fluid for a period of time, the calcium hydroxide on the surface dissolved gradually into the solution. At the same time, hydroxyapatite formed on the surface indicating the implantation of calcium into titanium indeed improves the bioactivity of the surface.