| 摘要 |
Starting from the base material of a board (1) that has each of its two faces surfaced with copper coating (2), the circuit is defined by means of the partial elimination of the copper by chemical etching. Following this, the punching of the unit is undertaken in order to obtain the bore holes (5) through which the electrical connection between the two faces of the circuit will be preformed. This connection is performed by means of a chemical metallizing in which a metal layer (8) from a nickel-phosphorous base alloy is applied to the holes (5) and to the area surrounding them, leaving the board, after the application of a solder mask, identification ink and conductive inks, in a condition to pass under the soldering jet, which will fill the metallized bore holes (5) with a tin/lead mass. <IMAGE> |
