Oblique Pillar Members for Stacked Semiconductor Substrate Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor devices with stacked substrates, underfill resin bleeding out around the semiconductor chip prevents substrate connecting members from being aligned with electrode terminals of the second semiconductor chip, leading to increased wiring distance and potential performance degradation or malfunction.
Innovation Solution
The semiconductor device incorporates obliquely extending pillar members between the substrates, with their ends connected to pads on both substrates, allowing for reduced wiring distance and improved alignment of substrate connecting members over the bleed-out area, thus minimizing the wiring distance and enhancing performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If substrate connecting members are positioned over the semiconductor chip area, then alignment with electrode terminals is improved, but underfill resin bleeding prevents proper alignment and connection
Solution Approach 1:
The pillar members are positioned obliquely between the first and second substrates, utilizing the vertical dimension to bridge the horizontal displacement caused by resin bleeding. This dimensional transition allows the connecting members to reach the electrode terminals despite the resin extending beyond the chip periphery in the horizontal plane.
Solution Approach 2:
The pillar members are configured with asymmetric positioning relative to the substrate surfaces, with different insertion depths and angles on each side. This asymmetric arrangement compensates for the non-uniform resin bleeding pattern and enables precise alignment with the electrode terminals of the second semiconductor chip.
2Speed
If wiring distance is reduced by repositioning substrate connecting members, then transmission speed increases, but alignment with electrode terminals becomes difficult due to resin bleeding
Solution Approach 1:
By transitioning from horizontal to oblique positioning, the pillar members reduce the effective wiring distance through the vertical dimension while maintaining alignment capability. This allows the connecting members to reach the electrode terminals more directly, reducing the overall signal path length.
Solution Approach 2:
The asymmetric configuration of pillar members with varying angles and depths enables each connector to be optimally positioned for its specific electrode terminal, minimizing individual wiring distances while maintaining precise alignment despite the presence of bleeding resin.
3Reliability
If pillar members are positioned obliquely to reduce wiring distance, then transmission performance improves, but manufacturing complexity increases
Solution Approach 1:
The oblique positioning of pillar members is implemented as a segmented solution, where each pillar is independently configured with specific angles and depths. This segmentation allows the complex oblique arrangement to be manufactured through separate positioning and insertion steps, making the complex structure more manageable and manufacturable.
Data Source
AI summary
A semiconductor device includes a first substrate, a second substrate stacked over the first substrate, and a pillar member extending obliquely between the first and second substrates. The first substrate includes a mounting surface on which a semiconductor chip is mounted, with a resin interposed between the semiconductor chip and the mounting surface and extending beyond the periphery of the semiconductor chip on the mounting surface. The first substrate further includes a first pad forming part of the mounting surface and disposed outside the resin. The second substrate includes a second pad forming part of its surface facing toward the mounting surface. The second pad at least overlaps the resin when viewed in a direction in which the second substrate is stacked over the first substrate. The pillar member has first and second ends joined to the first and second pads, respectively, to electrically connect the first and second substrates.