| 摘要 |
<p>1471163 Microcircuits; printed circuits HUGHES AIRCRAFT CO 8 Oct 1974 [9 Oct 1973] 43541/74 Heading H1R A hybrid microcircuit 10 is marked for identification of positions, values, and connections of circuits and components by coating with a thick layer of photoresist, masking, exposing to define the markings, developing, washing, drying and heat treating to darken the exposed portions which remain. Thus a film resistor 12 is marked R34 and its limits are defined by dots 14; a transistor is marked Q3 adjacent its pad 16, its emitter electrode 18 and its base electrode 20 while the emitter connection is marked E. Similarly an integrated circuit chip is marked U5 adjacent its location marked 22, while bonding wires are marked 24 and a capacitor chip 28 is marked C12 and its location is marked. Crossover wires are marked 30, and other instructions, e.g. resistor values, type of adhesive, and type of wire bond may also be marked.</p> |
