Multi-Core Wiring Substrate for Thin, Warp-Resistant Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-density and high-performance electronic devices require circuit boards with improved reliability, particularly in terms of warpage control, thermal, electrical, and mechanical properties, which is challenging due to the limitations of existing dielectric layers and metal wiring layers.
Innovation Solution
A wiring substrate design featuring multiple core layers with through vias and adhesion layers, where glass or dielectric polymer core sections are used to enhance stiffness and electrical connectivity, allowing for increased wiring freedom and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If the dielectric layer thickness is reduced to achieve thinner circuit board, then the circuit board thickness is reduced, but the warpage control becomes difficult and electrical, thermal, and mechanical properties degrade
Solution Approach 1:
The patent employs a composite structure consisting of multiple core layers (including glass core layers) stacked between wiring layers. This composite construction provides a low CTE and high modulus to counteract warpage, while maintaining overall thinness. The glass core layers specifically contribute to dimensional stability and mechanical strength, resolving the contradiction between thinness and reliability.
2Reliability
If glass substrate is used to achieve low CTE and high modulus for warpage control, then warpage is reduced, but handling and processing becomes challenging
Solution Approach 1:
The glass substrate is divided into multiple separate core layers that are stacked and processed individually. Each glass core layer can be handled, processed, and assembled separately, making manufacturing much easier compared to handling a single large glass substrate. This segmentation maintains the low CTE and high modulus benefits while improving manufacturability.
Solution Approach 2:
Adhesion layers are introduced between the glass core layers and other substrate components to facilitate handling and assembly. These intermediary layers enable easier processing and bonding of the glass core layers without requiring direct manipulation of the glass surfaces themselves.
3Strength
If multiple core layers are stacked to increase stiffness and wiring freedom, then substrate stiffness and wiring freedom are improved, but device complexity increases
Solution Approach 1:
The multiple core layers serve multiple functions simultaneously: they provide structural stiffness, control thermal expansion, enable wiring freedom through through-vias, and offer electrical isolation. This multi-functionality justifies the increased structural complexity by delivering multiple performance benefits from a single design feature.
Data Source
AI summary
Embodiments of a wiring substrate is provided. Embodiments include a first redistribution layer, a first core layer disposed on the first redistribution layer, a second core layer disposed on the first core layer, a first adhesion layer disposed between the first core layer and the second core layer, and a second redistribution layer disposed on the second core layer. In some cases, the first core layer includes a first core section and a first core pad disposed on a top surface of the first core section, wherein the second core layer includes a second core section and a second core pad disposed on a bottom surface of the second core section. The first core layer and the second core layer are electrically connected to each other through the first core pad and the second core pad.