摘要 |
A chip carrier package is made by using a laser-ablatable solder mask to cover areas of conductive traces on the surface of a substrate that were left uncovered during conventional processes using photoresist. These areas of the conductive traces are uncovered by using a laser to remove overlying portions of the solder mask. If a YAG laser is used, the conductive traces are removed at the same time the solder mask ablated. However, is a CO2 laser is used, a conventional etching process removes the exposed portions of the traces after the solder mask is ablated.
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