METHOD FOR PRE-EPITAXIAL TREATMENT OF SURFACE OF GERMANIUM SUBSTRATE Russian patent published in 2013 - IPC H01L21/302 

FIELD: chemistry.

SUBSTANCE: method for pre-epitaxial treatment of the surface of a germanium substrate involves removing the oxide layer from the surface of the substrate, cleaning the germanium surface from inorganic impurities and passivation of the substrate surface. The oxide is removed from the germanium surface by immersing the substrate into hydrochloric acid solution with concentration of 30-40 wt % for 2-4 minutes. Germanium is cleaned from inorganic impurities by immersing the substrate into a solution which contains hydrofluoric acid, hydrogen peroxide, tartaric acid and water for 0.5-1.5 minutes; passivation of the germanium surface is carried out in hydrochloric acid solution with concentration of 30-40 wt % for 2-5 minutes. The substrate surface is prepared at temperature of 19-23°C.

EFFECT: method simplifies the process of pre-epitaxial treatment of the surface of a germanium substrate by cutting the number of treatment steps with minimal modification of the surface of the substrate.