Moisture corrosion inhibitor layer for Al-alloy metallization layers for electronic devices and corresponding manufacturing method

The invention relates to a method of producing a protective inhibitor layer of moisture-generated corrosion for aluminum (Al) alloy metallization layers (1), particularly in semiconductor electronic devices. The method of this invention comprises chemically treating the metallization layer (1) in at least two steps using a mixture of concentrated nitric acid and trace phosphoric acid, in order to produce a thin protective phosphate layer (3). Alternatively, the method comprises dipping the electronic device at least once in a mixture of a polar organic solvent and phosphoric acid (H3PO4) or phosphate derivatives thereof in low percent amount, e.g. with a phosphate reactant such as orthophosphoric acid or even R-HxPOy, where R is an alkaline type of ion group or an alkyl radical. The thin film (3) is formed on top of a thin layer (2) of native aluminum oxide hydrate Al2O3.xH2O.