Synthesis of crystalline TiN and Si particles by laser ablation in liquid nitrogen

Laser ablation of titanium and silicon targets immersed in liquid nitrogen was carried out using a YAG laser at 1.06 mu m. Synthesized particles were collected and were characterized by TEM, SEM, EDS, XRD, and XPS. In the case of a titanium target, the synthesized particles had an atomic ratio of N/Ti=0.4 and a polycrystalline structure with many XRD peaks of TiN. This result indicates the usefulness of laser ablation in liquid nitrogen for synthesizing nitrides. On the other hand, in the case of a silicon target, the nitridation of the synthesized particles was negligible, and the synthesized particles had a polycrystalline structure of pure cubic silicon. This means that the oxygen-free environment realized by liquid nitrogen is useful for synthesizing particles with negligible oxidation.