Glass Skip Layer Air Gaps for High-Speed SERDES Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current skip layer architectures in electronic packages, which rely on buildup film for dielectric material, are inadequate for future serializer/deserializer interface specifications due to high dielectric constants, leading to suboptimal electrical performance and increased Z-height and fabrication costs.
Innovation Solution
Implementing skip layer routing with glass core layers that include air gaps above and below SERDES traces, utilizing glass layers with patterned cavities to form air gaps, which significantly reduce dielectric constant and improve electrical performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If buildup film is used for dielectric material in skip layer architecture, then the structure can be fabricated with current processes, but the dielectric constant is too high for future SERDES interface specifications
Solution Approach 1:
The patent changes the dielectric material parameter from buildup film (high dielectric constant) to air gaps (low dielectric constant approximately 1.0). This parameter change directly addresses the electrical performance requirements for future SERDES interfaces by reducing signal loss and improving signal integrity through the lower dielectric constant material.
Solution Approach 2:
The patent creates a composite structure combining glass core layers with air gaps formed by patterned cavities. This composite approach integrates the mechanical stability of glass with the low dielectric constant benefit of air, achieving both structural integrity and improved electrical performance for high-speed interfaces.
2Reliability
If air gaps are formed in glass core layers, then dielectric constant is reduced and electrical performance is improved, but fabrication complexity increases
Solution Approach 1:
The patent performs preliminary patterning of cavities in the glass core layers before final assembly. By pre-forming the cavity patterns in each glass layer, the subsequent alignment and bonding process becomes more straightforward, reducing the overall fabrication complexity despite the added step of cavity formation.
Solution Approach 2:
The patent divides the structure into multiple glass core layers with cavities formed in specific patterns. This segmentation allows the air gaps to be created in a controlled, modular manner rather than attempting to form complex three-dimensional air structures in a single step, thereby managing fabrication complexity.
3Length of stationary object
If air gaps are implemented in skip layer routing, then Z-height is minimized, but manufacturing precision requirements increase
Solution Approach 1:
The patent designs the glass core layers with complementary cavity patterns that self-align during the bonding process. The cavities in adjacent layers are positioned to interlock or align automatically, reducing the need for high-precision external alignment and thereby minimizing Z-height without proportionally increasing manufacturing precision requirements.
Solution Approach 2:
The patent creates a uniform bonding interface across the glass core layers by designing the cavity patterns to maintain consistent spacing and alignment references. This equipotential approach ensures that the entire bonding surface aligns uniformly, reducing the stringency of precision requirements while achieving minimal Z-height.
Data Source
AI summary
Embodiments disclosed herein include electronic packages. In an embodiment, the electronic package comprises a first layer, where the first layer comprises glass, a second layer over the first layer, where the second layer comprises glass, and a third layer over the second layer, where the third layer comprises glass. In an embodiment, a pair of traces are in the second layer, and a first gap is below the pair of traces, where the first gap is in the first layer and the second layer. In an embodiment, a second gap is above the pair of traces, where the second gap is in the second layer and the third layer.