Low temperature deposition of TiB2 by inductively coupled plasma assisted CVD

Inductively coupled plasma (ICP) chemical vapor deposition (CVD) was used to deposit titanium diboride (TiB2) films on H13 steel and (100) Si wafer substrate using a gas mixture of TiCl4, BCl3, H2 and Ar. The effects of the ICP on the TiB2 film properties were investigated. TiB2 films with high hardness (> 40 GPa) could be prepared at relatively low temperatures (400–250 °C) using ICP. The hardness increased with the ICP power and gas flow ratio of TiCl4/BCl3. The film structure also changed from a (100) preferred orientation to a random orientation with increasing rf power. It is believed that the high hardness of the TiB2 films resulted from the strong chemical bonding of the stoichiometric TiB2 films, the nano-sized small grains of TiB2.