Chip package having a glass fiber substrate
A chip package which includes a glass fiber substrate made of FR-4 fiberglass is provided. The chip package further includes a substrate pad which is a stacked metal structure with a certain thickness and composed of a nickel layer, a palladium layer, and a gold layer, or a nickel layer and a gold layer stacked over at least one first circuit layer in turn. A total thickness of the substrate pad is 3.15-5.4 μm. The glass fiber substrate and the substrate pad can bear positive pressure generated during wire bonding. Thereby at least one solder joint is formed on the substrate pad precisely and integrally. This helps reduction in material cost for manufacturers.
1 . A chip package comprising:
a glass fiber substrate which is made of FR-4 fiberglass and provided with a first surface and a second surface opposite to the first surface; wherein at least one first circuit layer is disposed on the first surface;
wherein at least one second circuit layer is arranged at the second surface of the glass fiber substrate; wherein at least one first blind hole and at least one second blind hole are formed on the first surface of the glass fiber substrate by drilling; wherein the first blind hole and the second blind hole are penetrating the first surface and the glass fiber substrate to be communicating with the second circuit layer; wherein the first circuit layer is extending from the first surface and through an inner surface of both the first blind hole and the second blind hole to be electrically connected with the second circuit layer,
at least one chip which is disposed on the first circuit layer on the first surface of the glass fiber substrate and provided with at least one chip pad;
at least one substrate pad which is arranged at the first circuit layer on the first surface of the glass fiber substrate and composed of a nickel (Ni) layer, a palladium (Pd) layer, and a gold (Au) layer stacked over the first circuit layer in turn to form a stacked metal structure with a certain thickness; or the substrate pad is a stacked metal structure with a certain thickness and composed of a nickel (Ni) layer and a gold (Au) layer stacked over the first circuit layer in turn; a total thickness of the substrate pad is 3.15-5.4 μm for increasing structural strength of the substrate pad;
wherein the substrate pad is formed by the Ni layer, the Pd layer, and the Au layer stacked over one another; wherein a thickness of the Ni layer in the substrate pad is 3-5 μm; wherein a thickness of the Pd layer in the substrate pad is 0.1-0.2 μm; wherein a thickness of the Au layer in the substrate pad is 0.05-0.2 μm;
wherein the substrate pad is formed by the Ni layer and the Au layer stacked over each other;
wherein a thickness of the Ni layer in the substrate pad is 3.1-5.2 μm; wherein a thickness of the Au layer in the substrate pad is 0.05-0.2 μm;
at least one bonding wire generated by wire bonding and provided with two ends respectively being welded to the chip pad of the chip and the substrate pad corresponding to the chip pad to form a solder joint on the chip pad and on the substrate pad; and
a glass fiber insulating layer made of FR-4 fiberglass and disposed on the glass fiber substrate by injection molding for covering and sealing the chip, the substrate pad, and the bonding wire;
wherein the glass fiber insulating layer further includes a first surface on which an outer protective layer is disposed;
wherein the chip and the first circuit layer on the first surface of the glass fiber substrate 1 are electrically connected with each other by the bonding wire;
wherein the glass fiber substrate and the substrate pad are able to withstand positive pressure generated during wire bonding when the solder joint is formed on the substrate pad correspondingly; thereby the solder joint is formed on the substrate pad precisely and integrally.
2 . The chip package as claimed in claim 1 , wherein the substrate pad is produced by chemical plating.
3 . The chip package as claimed in claim 1 , wherein the substrate pad is produced by electroplating.
4 . The chip package as claimed in claim 1 , wherein the substrate pad is produced by chemical plating.
5 . The chip package as claimed in claim 1 , wherein the substrate pad is produced by electroplating.