Wafer level assembly package
AssigneeAdvanced Semiconductor Engineering, Inc.
InventorsChi-Yu Wang, Tai-Yuan Huang
Life of this patent
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Abstract
A wafer level package mainly comprises a semiconductor wafer and a plurality of bonding pads disposed on the active surface of the wafer. It is characterized in that there is a protection layer formed on the back surface of the wafer, wherein the wettability of the solder material with the protection layer is lower than the wettability of the solder material with the bonding pads. In such a manner, the protection layer will prevent the back surface of the wafer from being contaminated with the solder material. Moreover, when a UBM layer is further provided on the bonding pad, the wettability of the solder material with the protection layer is lower than the wettability of the solder material with the UBM layer.
Claims14
A wafer level assembly package, comprising:
- a semiconductor wafer having an active surface, a back surface and a plurality of bonding pads formed on the active surface;
- a plurality of bumps disposed above the bonding pads, wherein the bumps are made of a solder material and wherein an under-bump-metallurgy layer is interposed between one of the bonding pads and the corresponding bump;
- and
- a protection layer formed on the back surface, wherein the wettability of the solder material with the protection layer is lower than the wettability of the solder material with the under-bump-metallurgy layer.
A semiconductor device, comprising:
- a chip having an active surface, a back surface and a plurality of bonding pads formed on the active surface;
- a plurality of bumps disposed on the bonding pads, wherein the bumps are made of a solder material and wherein an under-bump-metallurgy layer is interposed between one of the bonding pads and the corresponding bump;
- and
- a protection layer formed on the back surface, wherein the wettability of the solder material with the protection layer is lower than the wettability of the solder material with the under-bump-metallurgy layer.
Dependencies are inferred from the claim text.