manufacturing process of printed circuit and printed circuit manufacturing process using it

摘要

In the mfr. of printed circuits where a metallic substrate is possibly provided with holes matching any points which require soldering etc., and is then coated with a layer of insulation, followed by an extra process in which the conductors are formed, in order to form the insulating layer, the surface of the metal substrate is oxidised. After forming the conductors on the insulant, a second layer of insulation may be applied which covers the conductors at least partially and more conductors can be formed on the second layer of insulation. The substrate is pref. Al, anodically oxidised to form the insulant, the pores in the oxide being sealed with an insulating matl. The Al provides a light, inexpensive substrate, easily shaped and fulfilling several functions, e.g. including heat sinks.