Abstract: A method of planarizing the surface of a semiconductor device comprising a substrate carrying on its surface a contact configuration, which method essentially consists in that the following steps are successively carried out:(a) depositing a silicon nitride layer,(b) depositing a lacquer layer, whose free surface is substantially flat,(c) progressively attacking by plasma the lacquer layer until the farthest projecting parts of the silicon nitride layer are completely exposed, the complete appearance of these farthest projecting parts being detected by recording the intensity variations of an emitted jet of nitrogen,(d) attacking simultaneously by plasma the silicon nitride layer and the remaining lacquer until the contact configuration completely appears.

Abstract: A method of selectively etching a titanium oxide layer with a view to the formation of a mask for the localization of the anodic oxidation of an underlying metallic layer.The method is characterized in that the material comprising the said titanium oxide layer is dipped in a solution of hydrogen peroxide and ammonia.Application to the formation of contacts on semiconductor devices.

Abstract: A method of etching aluminium oxide and/or cleaning aluminium surfaces with an etchant consisting of a solution of a fluoride in an organic solvent, which solution is substantially free from hydrofluoric acid and unbound water.

Abstract: A method of manufacturing a semiconductor device having a pattern of conductors, according to which method an auxiliary layer is formed which consists of two different sub-layers in which the negative of the desired pattern is provided and which is covered with a metal layer, in which the auxiliary layer and the said metal layer are then removed selectively.The method is characterized in that the auxiliary layer comprises a lowermost layer of an anodically oxidizable metal and an uppermost layer of the oxide of the said metal and may be used in the manufacture of semiconductor devices, especially transistors for very high frequencies and integrated circuits.