Interaction of tantalum with fluorine-containing capacitively coupled radiofrequency plasma

The process of tantalum etching in discharges within SF6 and CF4+O2 has been studied at controlled fluxes of neutral and charged particles incident on the surface. It is shown that metal etching stems from interaction with fluorine atoms and it is accelerated by ionic bombardment of the surface in discharge in all the gases studied, whereas electronic bombardment affects the character of the processes on tantalum surface in discharge within CF4+O2 and SF6 in different ways. Effective activation energy of Ta etching has been determined for different ion and electron fluxes. Possible mechanisms of influence of metal surface bombardment by charged particles on the character of the heterogeneous processes have been discussed