“…The resulting HA, Ag-HA, and Si-HA powders exhibited an average particle size of 70 nm [101,103]. The investigations of the precursor powders and targets for sputtering were previously described [100,101,103]. It is very important to note that, in the case of Si-HA powder containing 1.22 and 4.9 at.% of Si, the preparation of the target resulted in the formation of the CaP phases HA and tricalcium phosphate (TCP), as determined by X-ray powder diffraction [100,101].…”