Method of fabricating printed circuit board (pcb) substrate having a cavity
AssigneeAvago Technologies General IP (Singapore) Pte. Ltd.
InventorJack Ajoian
Life of this patent
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Abstract
A method is provided for fabricating a substrate having multiple metal layers separated by one or more dielectric layers, respectively. The method includes forming a cavity in at least one dielectric layer through an exposed portion of a top dielectric layer of the substrate, applying metal to side and bottom surfaces of the cavity, forming a pattern through a portion of the metal applied to the bottom surface of the cavity, and micro-etching the metal applied to the bottom surface of the cavity. The micro-etching extends the pattern through a remaining portion of the metal applied to the bottom surface of the cavity.
Claims20
A method of fabricating a substrate having a plurality of metal layers separated by one or more dielectric layers, the method comprising:
- forming a cavity in at least one dielectric layer through an exposed portion of a top dielectric layer of the substrate;
- applying metal to side and bottom surfaces of the cavity;
- forming a pattern through a portion of the metal applied to the bottom surface of the cavity;
- and
- micro-etching the metal applied to the bottom surface of the cavity, the micro-etching extending the pattern through a remaining portion of the metal applied to the bottom surface of the cavity.
A method of fabricating a substrate, comprising:
- forming a plurality of metal layers separated by one or more dielectric layers, a top metal layer of the plurality of metal layers defining a first opening that exposes a portion of a top dielectric layer of the plurality of dielectric layers;
- applying a photoresist pattern over the top metal layer, the photoresist pattern defining a second opening over the first opening in the top metal layer;
- ablating the top dielectric layer using a first laser through the first and second openings to form a cavity through at least the top dielectric layer;
- plating metal to side and bottom surfaces of the cavity;
- ablating the plated metal on the bottom surface of the cavity using a second laser to form a pattern through a portion of the plated metal on the bottom surface of the cavity;
- and
- micro-etching the plated metal on the bottom surface of the cavity to extend the pattern through a remaining portion of the plated metal applied to the bottom surface of the cavity.
Dependencies are inferred from the claim text.