Improvements in or relating to information storage devices

A magnetic storage element is made by vapour deposition of Ni Fe alloy on a substrate of conductive material such as aluminium, silver or copper. As shown in Fig. 1 a substrate 1 is suspended over a crucible 2 containing the alloy and within a bell jar 3. The substrate is heated to a temperature 250-400 DEG C. by heating elements 5 during deposition, and a magnetic field of 80 oersted is applied by electromagnet 6. The alloy which may have a composition in the range 80/20 Ni Fe to 85/15 Ni Fe is foiled by an R.F. induction heating coil 7. An electrostatic field used to clean the substrate by ionic bombardment prior to deposition is provided by supplying A.C. to a pair of electrodes of which one 8 is shown. A heat shield 9 is provided. Conductors may be deposited on top of the magnetic film, and the substrate may be itself formed by vacuum deposition. A layer of silicon monoxide may separate the substrate and the film. A mask or etching techniques may be used to provide separated portions of magnetic film. Specification 880,383 is referred to.