Padless high density circuit board and manufacturing method thereof
AssigneeSilicon Integrated Systems Corp.
InventorsHan-Kun Hsieh, Wei-Feng Lin
Life of this patent
Estimating the term…
Abstract
A padless high density circuit board and manufacturing method thereof. The method includes providing a circuit board substrate having a dielectric layer on a surface, forming external wiring, having a plurality of external terminals with a width as large as or less than the external wiring on the dielectric layer, forming a solder mask over the dielectric layer and the external wiring with a plurality of solder mask openings exposing the external terminals, with diameters at least as large as the widths of the external terminals exposed thereby, and forming a plurality of conductive bumps on the external terminals exposed by the solder mask openings for connection with an external device in a subsequent assembly process.
Claims19
A padless high density circuit board, comprising:
- a circuit board substrate having a dielectric layer on its surface;
- external wiring, having a plurality of external terminals with a width as large as or less than the external wiring, formed on the dielectric layer;
- a solder mask over the dielectric layer and the external wiring with a plurality of solder mask openings exposing the external terminals, with diameters at least as large as the widths of the external terminals exposed thereby;
- and
- a plurality of conductive bumps formed on the external terminals exposed by the solder mask openings for connection with an external device in a subsequent assembly process.
A padless high density circuit board for connection with an external device with a bump or lead, comprising:
- a circuit board substrate having a dielectric layer on a surface;
- external wiring, having a plurality of external terminals with a width as large as or less than the external wiring, formed on the dielectric layer;
- a solder mask over the dielectric layer and the external wiring with a plurality of solder mask openings exposing the external terminals, with diameters at least as large as the widths of the external terminals exposed thereby;
- and
- a plurality of conductive bumps, not higher than the solder mask, formed on the external terminals exposed by the solder mask openings.
A padless high density circuit board for connection with an external device without a bump or lead, comprising:
- a circuit board substrate having a dielectric layer on a surface;
- external wiring, having a plurality of external terminals with a width as large as or less than the external wiring, formed on the dielectric layer;
- a solder mask over the dielectric layer and the external wiring with a plurality of solder mask openings exposing the external terminals, with diameters at least as large as the widths of the external terminals exposed thereby;
- and
- a plurality of conductive bumps, about 20 μm to 60 μm higher than the solder mask, formed on the external terminals exposed by the solder mask openings.
Dependencies are inferred from the claim text.