Abstract: A method of manufacturing electronic devices, in particular, but not exclusively, semiconductor devices, and apparatus for carrying out such a method, in which method wafers 1, which are provided at a surface 2 with a material 3 to be removed, are subjected, while being divided into successive batches, to a wet treatment in a bath 4 containing a solution 5 of an active component in a solvent. The successive batches of wafers 1 are immersed in the solution 5 at first time intervals during the wet treatment of the successive batches, which first time intervals each consist of a processing period during which the material 3 is removed from the surface 2 of the wafers 1, thereby forming ionic components, and a waiting period following the removal of the wafers 1 from the bath 4 at the end of the processing period.

Abstract: A method of manufacturing a semiconductor device, in which a layer of photolacquer (5) containing as a photoactive component a diazo oxide is provided on a semiconductor substrate. Of this layer, parts (9) are irradiated by a first patterned irradiation (7) and these parts are then rendered poorly developable by an intermediate treatment. Subsequently, the lacquer layer (5) is subjected to a second non-patterned irradiation (11) and is then developed. According to the invention, in the parts (9) irradiated by the first irradiation a pigment is formed, which absorbs radiation having a wavelength at which diazo oxide is photosensitive. The second irradiation is carried out with radiation of that wavelength. Thus, lacquer tracks having a rectangular profile can be obtained in a simple manner.