Abstract: To coat a substrate with a thin layer of pure platinum oxide, an insulating and transparent substance, recourse is had to a cylindrical magnetron comprising means for generating an axial magnetic field in an enclosure containing rarefied oxygen, an axial cathode at least coated with platinum and a cylindrical grid forming an anode and coaxially surrounding the cathode so as to reserve an annular zone outside the grid. The substrate is placed in the said zone so that its surface to be coated by the thin layer is shielded from the impact of electrons. This shielding can be obtained by a particular shape given to the bars constituting the grid or by the positioning of obstacles in the said zone. It then suffices to heat the thin layer, whether or not locally, to above 250.degree. C., to convert it into conducting and opaque platinum.

Abstract: The target of a device for cathodic sputtering at a high deposition rate on a substrate placed within a pumped enclosure is brought to a negative potential with respect to an anode. A gas is admitted at a pressure P into the space formed between the target and the anode, a high gas-pressure gradient being established between the target and the substrate. A magnetic field H is produced in a direction parallel to the target surface located opposite to the substrate and a suppressor screen is placed around the target.

Abstract: A method and apparatus for producing a thin semi-conductor coating on a substrate in a vacuum enclosure, by depositing on the substrate a semi-conductor substance volatilized by a plasma from a source in the enclosure and also depositing on the substrate a metallic doping impurity volatilized by the plasma from another source in the enclosure.