| 摘要 |
1,094,865. Resistors. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 20, 1965 [Nov. 27, 1964], No. 44416/65. Heading H1S. To form (meandering) resistor elements from a cermet film 14 (Fig. 1), the film includes a sufficiently large proportion of metal (70%) to be attackable by a suitable etching solvent removal of the metal leaving behind a dielectric remnant which can be easily removed as by washing. To secure adhesion of a copper conductor film to the cermet an under layer 16a of aluminium, chromium/copper or aluminium copper/alloy is deposited so that, like the copper film 16b, it can be etched away by an etchant (ferric chloride solution) which does not attack the chromium in the cermet. The cermet film 14 is flash evaporated in a vacuum which if of Cr-SiO 2 must contain at least 70 atomic per cent of Cr on to an SiO substrate 12 on a heat-resistant glass base 10. The resistance of the cermet film is determined by monitoring the resistance of a separate slide and stopping deposition at the required value. Simultaneous evaporation of Cr and Cu produces the alloy under layer 16a and continuing evaporation of Cu, the layer 16b both of which are etched using photo-resist 18 to form the desired conductor patterns (Fig. 3, not shown). The cermet film is then etched to form separate (meandering) resistance elements by AlCl 3 using a further photo-resist and after cleaning is covered by a SiO film. The resistor panel so formed is cleaned ultrasonically and annealed in argon-hydrogen at 400-450‹ C. for a time determined by monitoring the value of one of the resistors. The value of individual resistors may subsequently be adjusted by local heating. The cermet film may be made using 90 at per cent Cr-10 mol. per cent SiO dissolved in a solution consisting of 1 lb. AlCl 3 .6H 2 O, 135g. ZnCl 2 , 30 ml. H 3 PO 4 and 400 ml. water. The film is depassivated before etching by contacting its surface with zinc pellets or powder. |
