PoP Package Wire Structure With Enlarged Tip Contact Area
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor packages with a PoP structure, insufficient connection area between stacked packages can lead to breakage due to stress concentration and inadequate contact area, particularly at the interface between wires and solder.
Innovation Solution
The semiconductor device incorporates a wire with a large-width part at its end, which protrudes from a resin layer and contacts the solder, increasing the connection area and improving reliability by using the same conductive material throughout, thus enhancing the structural integrity and reducing the likelihood of breakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional wire structure is used in PoP packages, then the device complexity is reduced, but the connection area is insufficient leading to breakage
Solution Approach 1:
The wire is divided into multiple sections with different cross-sectional areas: a first section with a first cross-sectional area and a second section with a second cross-sectional area that is larger than the first. This segmentation allows the wire to have both a thinner section for ease of manufacture and a thicker section for improved connection reliability and stress distribution.
Solution Approach 2:
The wire structure implements local quality by having different cross-sectional areas at different locations. The larger cross-sectional area is specifically positioned at the connection interface where higher reliability is needed, while other portions of the wire maintain a smaller cross-sectional area.
2Reliability
If the connection area between wire and solder is increased, then the reliability improves, but the manufacturing complexity increases
Solution Approach 1:
The wire manufacturing process is segmented into distinct stages: forming the wire with a first cross-sectional area, then selectively increasing the cross-sectional area at specific locations to create the second section. This segmentation allows standard manufacturing processes to be used for the bulk of the wire while applying additional processing only where needed.
Solution Approach 2:
The wire is preliminarily formed with a uniform cross-sectional area using standard manufacturing processes, and then the cross-sectional area is increased at specific locations in a subsequent step. This preliminary action simplifies the overall manufacturing process by separating the bulk formation from the localized modification.
3Area of stationary object
If a uniform wire structure is used, then the manufacturing is simpler, but the connection area is insufficient leading to stress concentration
Solution Approach 1:
The wire is segmented into a first section with a smaller cross-sectional area and a second section with a larger cross-sectional area. The second section is specifically positioned at the connection interface to provide increased connection area and reduce stress concentration, while the first section maintains a simpler structure.
Solution Approach 2:
The wire structure implements local quality by concentrating the increased cross-sectional area at the specific location where connection reliability is most critical, rather than uniformly increasing the cross-sectional area throughout the entire wire length.
4Strength
If the wire cross-sectional area is increased at the connection interface, then the resistance to physical impact improves, but the manufacturing precision requirements increase
Solution Approach 1:
The wire manufacturing process is segmented into controlled stages where the cross-sectional area is adjusted at specific locations. This segmentation allows for controlled increases in cross-sectional area at the connection interface while maintaining standard precision requirements for the remainder of the wire.
Solution Approach 2:
The cross-sectional area parameter of the wire is changed at specific locations to create the second section with a larger cross-sectional area. This parameter change is applied selectively rather than uniformly, allowing improved strength where needed while maintaining manufacturability.
Data Source
AI summary
A semiconductor device according to the present embodiment includes a first substrate, a resin layer, and a wire. The first substrate has a first face. The resin layer is provided on the first face and has a second face on an opposite side to the first face. The wire is provided so as to penetrate the resin layer and protrude from the second face. The wire includes a large-width part which is provided at an end of the wire protruding from the second face and which is wider than a width of the wire penetrating the resin layer. The large-width part is arranged so as to come into contact with the second face.