Inductively coupled plasma reactive ion etching of titanium thin films using a Cl2/Ar gas

Inductively coupled plasma reactive ion etching of titanium thin films patterned with a photoresist using Cl2/Ar gas was examined. The etch rates of the titanium thin films increased with increasing the Cl2 concentration but the etch profiles varied. In addition, the effects of the coil rf power, dc-bias voltage and gas pressure on the etch rate and etch profile were investigated. The etch rate increased with increasing coil rf power, dc-bias voltage and gas pressure. The degree of anisotropy in the etched titanium films improved with increasing coil rf power and dc-bias voltage and decreasing gas pressure. X-ray photoelectron spectroscopy revealed the formation of titanium compounds during etching, indicating that Ti films etching proceeds by a reactive ion etching mechanism.