Defined micropatterns of platinum thin films by inductively coupled plasma etching using SF₆/Ar/O₂ mixture gas

The reactive ion etching of platinum thin films is performed in inductively coupled plasma with optimised SF₆/Ar/O₂ mixture gas to fabricate micro-electrodes for high-K metal-insulator-metal capacitors. In this study, different fluoride-based gases were applied for platinum etching, and both the chemically and physically enhanced effects of etching were examined. Ar plasma was physically sputtered to attain a high etching rate and the varying amounts of oxygen were evaluated to reduce the fence defects caused by Ar-based physical sputtering etching. Scanning electron microscopy images revealed that oxygen plasma has successfully removed the fence effect. Using inductively coupled plasma reactive ion etching at an etching rate of 32.1 nm/min, the defined 0.5 μm-wide micropatterns of platinum thin films were generated.