37 Installation and maintenance of machines for the manufacture of semiconductor substrates, silicon discs, wafers, LCD-substrates, LCD-displays, semiconductor chips and/or solar cells; machines for the treatment, coating, polishing, cleaning and/or drying of substrates; combination drying and wet-treatment units for the processing of semiconductor substrates, silicon discs, wafers, LCD-substrates, LCD-displays, semiconductor chips and/or solar cells as well as their surfaces