Interposer Bonding Pad Structure for Temperature-Cycle Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing semiconductor packages face separation issues during reliability tests like temperature cycles due to a decrease in interface adhesion strength between the bonding pad and the insulating layer, leading to reliability concerns.
Innovation Solution
The semiconductor package incorporates an interposer with a bonding pad structure featuring a T-shaped cross-sectional design, where a first pad pattern is exposed from the surface and a second pad pattern with a greater width is positioned on top, creating an anchor effect that enhances mechanical coupling and prevents separation from the insulating layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional bonding pad structure is used, then the device complexity is low, but the interface adhesion strength decreases during temperature cycle tests
Solution Approach 1:
The bonding pad is divided into multiple segments: a first pad pattern exposed from the first surface and a second pad pattern positioned on the first pad pattern. This segmentation allows each part to serve specific functions - the first pad pattern provides bonding interface while the second pad pattern extends into the insulating layer to enhance adhesion, resolving the contradiction between simple structure and high reliability
Solution Approach 2:
The bonding pad structure transitions from a two-dimensional planar pattern to a three-dimensional configuration by positioning the second pad pattern on top of the first pad pattern and extending into the insulating layer. This dimensional change creates an anchor effect that significantly improves interface adhesion strength while maintaining manufacturing feasibility
2Reliability
If the bonding pad width is increased to improve adhesion, then the interface adhesion strength improves, but the area available for other components decreases
Solution Approach 1:
Instead of increasing the bonding pad area in the planar direction which would reduce available space, the structure extends vertically by positioning the second pad pattern on top of the first pad pattern and into the insulating layer. This vertical extension provides additional adhesion area without consuming horizontal space, resolving the contradiction between adhesion strength and available area
Solution Approach 2:
The second pad pattern is positioned on and overlaps with the first pad pattern, creating a nested configuration where the bonding pad structure occupies vertical space rather than horizontal space. This nesting approach allows the bonding pad to gain adhesion area without increasing its footprint on the interposer surface
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design significantly improves the reliability of the semiconductor package by maintaining the bonding pad's integrity during temperature cycle tests, ensuring stable performance and preventing separation from the insulating layer.
Implementation Method 1
The bonding pad has a T-shaped cross-sectional shape, thereby causing an anchor effect. This anchor effect causes mechanical coupling to limit and/or prevent the bonding pad from being separated from the insulating layer during a semiconductor reliability test, such as a temperature cycle TC.
Data Source
AI summary
A semiconductor package includes an interposer having a first surface and a second surface opposite to the first surface and including a plurality of bonding pads, and first and second semiconductor devices on the interposer. Each of the plurality of bonding pads includes a first pad pattern provided to be exposed from the first surface and having a first width and a second pad pattern provided on the first pad pattern and having a second width greater than the first width.