Glass Via Profile Shaping for Reduced Taper and Signal Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laser-assisted etching in glass cores results in via tapering, leading to increased resistance, current crowding, and insertion loss issues, limiting design flexibility and requiring expensive glass substrates.
Innovation Solution
Implement post-processing operations, such as using hardmask materials and selective etching, to mitigate via tapering, allowing for uniform deposition of conductive materials and enabling a wider range of via shapes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If laser assisted etching is used to form vias in glass core, then via formation is achieved, but via tapering occurs causing diameter reduction from surface to center
Solution Approach 1:
The patent applies preliminary action by forming a mandrel structure with a non-tapered or reduced-taper profile before depositing the conductive material. The mandrel is formed using spin coating and curing processes that create a predetermined geometry, which then serves as a template to prevent tapering during subsequent etching operations. This preliminary structuring ensures that the final via maintains uniform diameter throughout its length.
Solution Approach 2:
The mandrel acts as an intermediary element between the glass core and the conductive via material. It provides a physical template that defines the via geometry, mediating the formation process to achieve non-tapered walls. The mandrel is temporarily present during the etching process and is subsequently removed, having served its purpose of controlling the via shape.
2Manufacturing precision
If via tapering is reduced using expensive glass materials, then via narrowing is minimized, but manufacturing cost increases
Solution Approach 1:
The patent employs a disposable mandrel structure made from inexpensive materials that is formed, used to define the via geometry, and then removed. This temporary structure enables precise via formation in standard-cost glass substrates, replacing the need for expensive specialized glass materials. The mandrel's temporary nature and low material cost make this approach economically viable.
Solution Approach 2:
The patent changes the geometric parameters of the via formation process by introducing a mandrel with specific dimensional characteristics (non-tapered profile). This parameter change in the formation process allows achieving uniform via dimensions in standard glass substrates, eliminating the need for expensive glass materials with inherently better etching properties.
3Stability of the object's composition
If via diameter is reduced at center to accommodate glass properties, then structural integrity is maintained, but current crowding and resistance increase
Solution Approach 1:
The mandrel is formed in advance with a uniform diameter profile, preventing the natural tapering that would occur during laser etching. This preliminary structuring ensures that the via maintains sufficient diameter at the center region, preventing current crowding and maintaining low resistance while still accommodating the glass substrate's structural requirements.
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 approach reduces via tapering, improves signaling performance, optimizes insertion loss, and enables the use of lower-cost glass substrates while maintaining structural integrity.
Implementation Method 1
laser assisted etching has been proposed in order to form vias and other structures in the glass core
Implementation Method 2
The via openings may then be etched using an etching chemistry that is selective to the exposed regions over the unexposed regions
Data Source
AI summary
Embodiments disclosed herein include an electronic package that comprises a substrate with a first surface and a second surface opposite from the first surface. In an embodiment, the substrate comprises glass. In an embodiment, the electronic package further comprises an opening through the substrate from the first surface to the second surface, where the opening comprises a first end proximate to the first surface of the substrate, a second end proximate to the second surface of the substrate, and a middle region between the first end and the second end. In an embodiment, the middle region has a discontinuous slope at junctions with the first end and the second end.