Towards Atomic-Layer-Scale Processing of High Mobility Channel Materials in Acidic Solutions for N5 and N7 Technology Nodes

In this work the etching kinetics of Ge (100) is studied in acidic solutions containing and oxidizing agent. It is shown that the etch rate in the low etch-rate range is controlled by the concentration of the acid, oxidizing agent and the hydrodynamics of the system. The surface termination during etching has strong impact on the etching kinetics. Finally, we discuss the stability of the Ge (100) surface in water and relate this to the low solubility of the Ge suboxides