Surface finishes for high density interconnect architectures
AssigneeIntel Corporation
InventorsDavid Unruh, Srinivas V. Pietambaram
Life of this patent
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Abstract
An electroless nickel, electroless palladium, electroless tin stack and associated methods are shown. An example method to form a solder bump may include forming a layer of a second material over a first material at a base of a trench in a solder resist layer. The first material includes nickel and the second material includes palladium. The method further includes depositing a third material that includes tin on the second material using an electroless deposition process, and forming a solder bump out of the third material using a reflow and deflux process.
Claims25
An apparatus including a package comprising:
- the package comprising:
- solder resist layer;
- an electrode embedded in a bottom portion of the solder resist layer;
- and
- a solder bump extending through the solder resist layer to the electrode, the solder bump including an electroless nickel, electroless palladium, electroless tin (ENEPET) stack.
An apparatus including a package comprising:
- a first pair of electroless nickel, electroless palladium, electroless tin (ENEPET) stacks formed in a solder resist layer of the package having a first pitch;
- and
- a second pair of ENEPET stacks formed in the solder resist layer of the package having a second pitch, wherein the first pitch is greater than the second pitch,
The apparatus of claims, wherein a first ENEPET stack of the first pair of ENEPET stacks in the solder resist layer of the package comprises:
- the electroless nickel at a base of a trench in the solder resist layer;
- the electroless palladium over the electroless nickel;
- and
- the electroless tin deposited on the electroless palladium.
(canceled)
A method to form a solder bump comprising:
- forming a layer of a second material over a first material at a base of a trench in a solder resist layer, wherein the first material includes nickel and the second material includes palladium;
- depositing a third material that includes tin on the second material using an electroless deposition process;
- and
- forming a solder bump out of the third material using a reflow and deflux process.
A method to form a solder bump comprising:
- forming a first pair of electroless nickel, electroless palladium, electroless tin (ENEPET) stacks in a solder resist layer of a package;
- and
- contemporaneously with forming the first pair of ENEPET stacks in the solder resist layer of the package, forming a second pair of ENEPET stacks in the solder resist layer of the package, wherein a pitch between the first pair of ENEPET stacks is greater than a pitch between the second pair of ENEPET stacks.
Dependencies are inferred from the claim text.