Specific Process Knowledge/Etch/IBE⁄IBSD Ionfab 300/IBE magnetic stack etch

Results of Design of Experiments optimization of magnetic stack etching

Process parameters for the acceptance test

Parameter	Ti etch acceptance
Neutalizer current [mA]	450
RF Power [W]	800
Beam current [mA]	400
Beam voltage [V]	500
Beam accelerator voltage	500
Ar flow to neutralizer [sccm]	5.0
Ar flow to beam [sccm]	10.0
Rotation speed [rpm]	20
Stage angle [degrees]	5
Helium backside cooling [Torr]	37.5

Some SEM profile images of the etched stacks

Magnetic stack of Ta/MnIr/NiFe/Ta/Tao/Ta/MnIr/NiFe/Ta. Redeposition of etched material at photo resist. Profile ~78°	Etched magnetic stack with pool structure transfer. Chosen etch parameters result in severe footing	Etched magnetic stack with pool structure transfer. Chosen etch parameters result in severe trenching