Amorphization of ceramics by ion beams

The influence of the implantation parameters fluence, substrate temperature, and chemical species on the formation of amorphous phases in Al2O3 and α-SiC was studied. At 3000K, fluences in excess of 1017 ions.cm-2 were generally required to amorphize Al2O3; however, implantation of zirconium formed the amorphous phase at a fluence of 4 x 1016 Zr.cm-2. At 770K, the threshold fluence was lowered to about 2 x 1015 Cr.cm-2. Single crystals of α-SiC were amorphized at 3000K by a fluence of 2 x 1014 Cr.cm-2 or 1 x 1015 N.cm-2. Implantation at 10230K did not produce the amorphous phase in SiC. The micro-indentation hardness of the amorphous material was about 60% of that of the crystalline counterpart