Substrate Wiring Layer Current Distribution via Local Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods fail to evenly distribute current through vias on a substrate, leading to crowding at both ends, which can result in increased current density and potential breaks due to electromigration.
Innovation Solution
The substrate design features varying electrical resistance regions along the wiring layers, with regions upstream having higher areas and fewer apertures, and those downstream having lower areas and more apertures, to gradually increase resistance and inhibit current crowding at the vias.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If uniform wiring layer structure is used, then manufacturing is simple, but current crowds into vias at both ends
Solution Approach 1:
The wiring layer is designed with non-uniform structure where the width varies along the current flow direction. Specifically, the wiring layer has a wider width at regions farther from the power supply pad and narrower width near the power supply pad. This local variation in geometry creates corresponding variation in electrical resistance, with higher resistance regions positioned to redirect current away from end vias, thereby achieving uniform current distribution across all vias without complicating the overall manufacturing process.
2Reliability
If wiring layer resistance is increased to inhibit current crowding, then current distribution improves, but voltage drop increases
Solution Approach 1:
The wiring layer incorporates localized resistance variations through non-uniform width design. High resistance regions are strategically positioned between vias to redirect current flow and prevent crowding at end vias, while low resistance regions are maintained near the power supply pad and in areas where current collection is needed. This selective resistance distribution achieves uniform current sharing without creating excessive overall voltage drop, as the high resistance is only introduced where needed for current redistribution.
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 ensures even current flow through the vias, reducing the risk of electromigration and preventing current crowding at both ends, thereby enhancing the reliability of the substrate.
Implementation Method 1
a first wiring layer coupled to a second wiring layer through a plurality of vias, wherein the first wiring layer has a structure in which an area of a first region, which is enclosed by a first line segment and a second line segment, except an aperture located in the first region is greater than an area of a second region, which is enclosed by the second line segment and a third line segment, except an aperture located in the second region
Data Source
AI summary
Provided is a substrate including a first wiring layer coupled to another wiring layer through a plurality of vias, wherein in the first wiring layer, an area of a first region except an aperture is greater than an area of a second region except an aperture, the first region being enclosed by a first line segment passing through a first connection part of a first via and being parallel to a first short side of the first wiring layer and a second line segment passing through a second connection part of a second via and being parallel to the first short side, the second region being enclosed by the second line segment and a third line segment passing through a third connection part of a third via and being parallel to the first short side, the first, second, and third connection parts connecting to the first wiring layer.