High-performance and damage-free magnetic film etching using pulse-time-modulated Cl2 plasma

Magnetic films have been used to fabricate magnetic random access memory (MRAM) devices. A key issue for producing magnetic devices is the problems associated with magnetic film etching, in particular a low etching rate and sidewall deposition caused by non-volatile etching products. We recently found that plasma radiations degraded magnetic properties. To overcome these problems, we investigated the effects of a few tens of micro-second pulse-time-modulated (TM) plasma on magnetic film etching. In this study, we found that injecting negative ions from TM plasma produced no sidewall deposition and accomplished damage-free magnetic film etching.