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

We have developed a reactive ion etching (RIE) technique for magnetic films using pulse-time-modulated (TM) plasma. Using TM plasma etching can make the etching process high-performance and free of magnetic damage and corrosion. On the other hand, the conventional continuous wave discharge (CW) plasma etching process causes corrosion problems and degrades magnetic properties. We speculate that the negative ions injected from the TM plasma enhanced the chemical reaction on the magnetic film surface. We conclude that the TM plasma etching is a high-performance magnetic film etching process for fabricating magnetoresistive random access memory (MRAM).