GB1006076A - Improvements in or relating to methods of forming a pattern of conducting material ona substantially insulating support - Google Patents

Abstract

<PICT:1006076/C6-C7/1> A method of forming a pattern of conducting material on a substantially insulating support, e.g. for a mosaic screen in a light scanned television pick-up tube, comprises providing an electrode 2 on one side of the support 1 by depositing a layer of electrically conducting material thereon, dispersing a conducting stencil 6 close to the other side of the support, applying a potential difference between the electrode and the stencil to cause the stencil to be electrostatically attracted towards the electrode thereby being held in contact with the other side of the support, depositing material to form a plurality of discrete elements on to the other side through the stencil and subsequently dispersing the material of the electrode to remove the electrode. In one embodiment, the insulating support is a glass and the electrode 2 is of tellurium, the stencil being a fine metal mesh. Antimony, which is subsequently sensitized so as to be photosensitive is evaporated from an evaporator composed of platinum coated molybdenum wire of 0.01 inch diameter or of a coil of tungsten wire. The processing may be carried out within the pick-up tube itself, the electrode 2 removed during the bake-out period of the tube. The metal mesh may be moved a required distance from the support and subsequently used as an electrode during operation of the tube. In a further example, after the removal of the mesh, a layer of chromium is evaporated over the discrete elements and the support, and the elements subsequently etched off, leaving a mesh-like pattern of chromium on the insulating support.