| 摘要 |
<p>Printed circuits are fabricated by a process which employs initial chemical deposition of copper (12) on a predrilled substrate (11) followed by electroplating build-up of conductors (16) to desired pattern. The conductors (16) are then passivated by thinly plating them with a mechanically durable, chemically passive metal (17). To provide solder compatibility in are (15) where connections are to be made to the printed circuits, a plating of tin/lead (19) is applied in those are while masking (18) all other are to eliminate plating. The remaining exposed copper (12) is then etched away. An insulating solder mask (21) is then applied. </p> |
