Reactive Ion Etching of NiFe Film with Organic Resist Mask and Metal Mask by Inductively Coupled Plasma

Etching of NiFe films covered with an organic photo-resist or Ti was successfully performed by an inductively coupled plasma-reactive ion etching (ICP-RIE) system using CHF₃/O₂/NH₃ discharges exchanging CHF3 for CH₄ gas gradually. Experimental results showed that the organic photo-resist mask can be applied to the NiFe etching. In the case of the Ti metal mask, it was found that the etching-selectivity Ti against NiFe was significantly varied from 7.3 to ~0 by changing CHF₃/CH₄/O₂/NH₃ to CH₄/O₂/NH₃ discharges used in the ICP-RIE system. These results show that the present RIE of NiFe was dominated by a chemical reaction rather than a physical sputtering.