Mounted circuit substrate and method for fabricating the same for surface layer pads that can withstand pad erosion by molten solder applied over a plurality of times
AssigneeFujitsu Limited
InventorsKiyokazu Moriizumi, Manabu Watanabe
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Abstract
A mounted circuit substrate has at least one conductive layer. The side faces of a component mounting pad is formed on a surface of the substrate, and includes at least a columnar pattern made of a metal highly resistant to erosion by solder. The side faces of the component mounting pad are completely covered with an organic insulating layer. Therefore, the component mounting pad can withstand molten solder stresses accompanying component replacement even when component replacement is done many times.
Claims20
A mounted circuit substrate having at least one conductive layer, wherein side faces of a component mounting pad formed on a surface of said substrate, and including at least a columnar pattern made of a metal highly resistant to erosion by solder, are completely covered with an organic insulating layer.
A method for fabricating a mounted circuit substrate, wherein after a component mounting pad including at least a columnar pattern made of a metal highly resistant to erosion by solder is formed on a thin-film multilayer substrate having at least one conductive layer, an organic insulating layer is formed in such a manner as to cover said component mounting pad, and then said organic insulating layer is removed over entire surface thereof so as to provide a planarized surface until a top of said columnar pattern is exposed.
Dependencies are inferred from the claim text.