SC-1 Etching of Niobium and Titanium Nitride Thin Films

Dry etching techniques, ubiquitous in microelectronics fabrication, often result in challenging levels of undesired collateral plasma-induced damage. In this work, we demonstrate a wet etching alternative for the patterning of niobium (Nb) and titanium nitride (TiN) thin films using the Standard Cleaning 1 (SC-1) solution. We characterize the etching process through its time-evolution dynamics, supported by scanning-electron and atomic force microscopy assessment of the etched film morphology. The results suggest etch dynamics that are linked to native oxides and film microstructure. Overall, the manageable etch rates, the safe operation and the high material selectivity are attractive for practical use in microelectronics fabrication.