Package substrate having electrically connecting structure
A package substrate having an electrically connecting structure are provided. The package substrate include: a package substrate substance with at least a surface having a plurality of electrically connecting pads formed thereon, allowing an insulating protective layer to be formed on the surface of the package substrate substance and the electrically connecting pads and formed with a plurality of openings corresponding in position to the electrically connecting pads so as to expose a portion of the electrically connecting pads, respectively; and a metal layer provided on an exposed portion of the electrically connecting pads, walls of the openings of the insulating protective layer, and a circular portion of the insulating protective layer encircling each of the openings thereof, and provided with a slope corresponding in position to a bottom rim of each of the openings. Accordingly, solder bleeding and short circuits are prevented.
1. A package substrate having an electrically connecting structure, comprising:
a package substrate substance with at least a surface having a plurality of electrically connecting pads formed thereon and having an insulating protective layer, allowing the insulating protective layer to be formed on the electrically connecting pads and formed with a plurality of openings corresponding in position to the electrically connecting pads so as to expose the electrically connecting pads, respectively, wherein the package substrate substance is made of an organic or ceramic material, and the insulating protective layer is an outmost layer of the package substrate substance; and
a silver metal layer provided on an exposed portion of the electrically connecting pads, walls of the openings of the insulating protective layer, and a rim portion of the insulating protective layer encircling each of the openings thereof, wherein the silver metal layer is formed with a slope toward a bottom end of each of the openings and a bottom of the silver metal layer on the bottom end of each of the openings, such that the bottom of the silver metal layer is completely lower than a top end of each of the openings of the insulating protective layer.
2. The package substrate having an electrically connecting structure of claim 1 , further comprising a conductive layer provided on the exposed portion of the electrically connecting pads, on the walls of the openings of the insulating protective layer, on the rim portion of the insulating protective layer encircling each of the openings thereof, and beneath the silver metal layer.
3. The package substrate having an electrically connecting structure of claim 1 , further comprising a solder material provided on the silver metal layer.
4. The package substrate having an electrically connecting structure of claim 3 , wherein the solder material is a low-melting-point solder selected from the group consisting of tin/lead (Sn/Pb), tin/silver (Sn/Ag), tin/silver/copper (Sn/Ag/Cu), tin/copper (Sn/Cu), tin (Sn), and lead-free solder.
5. The package substrate having an electrically connecting structure of claim 1 , further comprising a surface treatment layer provided on the silver metal layer.
6. The package substrate having an electrically connecting structure of claim 5 , wherein the surface treatment layer is made of one selected from the group consisting of nickel/gold (Ni/Au), electroless nickel and immersion gold (ENIG), electroless nickel/electroless palladium/immersion gold (ENEPIG), immersion tin (IT), and direct immersion gold (DIG).
7. The package substrate having an electrically connecting structure of claim 5 , further comprising a solder material covering the surface treatment layer.
8. The package substrate having an electrically connecting structure of claim 7 , wherein the solder material is a low-melting-point solder selected from the group consisting of tin/lead (Sn/Pb), tin/silver (Sn/Ag), tin/silver/copper (Sn/Ag/Cu), tin/copper (Sn/Cu), tin (Sn), and lead-free solder.
9. The package substrate having an electrically connecting structure of claim 1 , further comprising a surface treatment layer provided on an upper surface and a side surface of the silver metal layer.
10. The package substrate having an electrically connecting structure of claim 9 , wherein the surface treatment layer is made of one selected from the group consisting of nickel/gold (Ni/Au), electroless nickel and immersion gold (ENIG), electroless nickel/electroless palladium/immersion gold (ENEPIG), immersion tin (IT), and direct immersion gold (DIG).
11. The package substrate having an electrically connecting structure of claim 9 , further comprising a solder material covering the surface treatment layer.
12. The package substrate having an electrically connecting structure of claim 11 , wherein the solder material is a low-melting-point solder selected from the group consisting of tin/lead (Sn/Pb), tin/silver (Sn/Ag), tin/silver/copper (Sn/Ag/Cu), tin/copper (Sn/Cu), tin (Sn), and lead-free solder.