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US 12,302,496 B2Granted
System and method to eliminate via striping
AssigneeDell Products L.P.
InventorsSandor Farkas, Bhyrav Mutnury
Life of this patent
Estimating the term…
Abstract
A printed circuit board includes metal layers, a metalized circuit via interconnecting a first one of the metal layers and a second one of the metal layers, and a back-drill hole drilled to remove metalization of the circuit via from a third metal layer adjacent to the second metal layer to a fourth metal layer at a first surface of the printed circuit board. The back-drill hole has a profile that includes a first undercut at a bottom of the first back-drill hole.
Claims18
A printed circuit board, comprising:
- a plurality of metal layers;
- a metalized circuit via interconnecting a first one of the metal layers and a second one of the metal layers;
- and
- a back-drill hole drilled to remove metallization of the metallized circuit via from a third metal layer adjacent to the second metal layer to a fourth metal layer at a first surface of the printed circuit board, wherein the back-drill hole has a profile that includes an undercut directly below the metallized circuit via.
1 more element
A method, comprising:
- forming, in a printed circuit board including a plurality of metal layers, a metalized circuit via interconnecting a first one of the metal layers and a second one of the metal layers;
- and
- drilling, into the printed circuit board, a back-drill hole to remove metallization of the metallized circuit via from a third metal layer adjacent to the second metal layer to a fourth metal layer at a first surface of the printed circuit board, wherein the back-drill hole has a profile that includes an undercut directly below the metallized circuit via.
A method, comprising:
- forming, in a printed circuit board including a plurality of metal layers, a metalized circuit via interconnecting a first one of the metal layers and a second one of the metal layers;
- drilling, into the printed circuit board, a back-drill hole to remove metallization of the metallized circuit via from a third metal layer adjacent to the second metal layer to a fourth metal layer at a first surface of the printed circuit board, wherein the back-drill hole is drilled with an undercut drill bit;
- and
- slewing the undercut drill bit in the back-drill hole to form an undercut directly below the metallized circuit via.
1 more element
Dependencies are inferred from the claim text.