Recognition: unknown
Interposer frame and method of manufacturing the same
Pith reviewed 2026-05-06 21:31 UTC · model grok-4.3
The pith
A method builds an interposer by plating conductive sidewalls inside drilled holes of a continuous fiberglass dielectric then stripping the outer metal layers to leave only the vertical conductors.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The central claim is that a continuous fiberglass dielectric can be drilled, plated on the hole walls, and then selectively etched on its outer surfaces to produce isolated conductive through-substrate holes without delamination, after which a central die cavity and opposing substrates can be added to complete a functional interposer frame.
What carries the argument
Selective removal of the outer conductive layers after full plating of the TSH sidewalls, which leaves only the sidewall conductors embedded in the unbroken fiberglass dielectric.
If this is right
- The finished frame can electrically connect connectors on the first substrate to connectors on the second substrate through the preserved sidewall conductors.
- The central opening allows a die to sit inside the interposer thickness, reducing overall package height.
- Removal of the outer conductive layers after plating prevents unintended lateral shorts between adjacent TSHs.
- The passivation layer on the second substrate protects the exposed conductors during subsequent assembly steps.
Where Pith is reading between the lines
- Because the fiber reinforcement is never severed across the full thickness, the structure may tolerate higher bonding pressures or temperatures than interposers built from laminated or drilled-and-filled cores.
- The same sequence could be adapted to create interposers with non-circular TSH cross-sections or with multiple concentric rings of holes around the central cavity.
- If the selective etch step can be made self-aligned to the hole entrances, the process might reduce the number of masking operations compared with conventional via-last flows.
Load-bearing premise
The fiberglass fibers and surrounding base material stay mechanically and electrically continuous after drilling, plating, and selective etching so the sidewall conductors do not delaminate when the outer substrates are later bonded.
What would settle it
Cross-section images or electrical tests showing cracks, fiber breakage, or open circuits along the plated TSH walls after thermal cycling or substrate bonding would show the method fails to preserve continuity.
Figures
read the original abstract
1 . A method, comprising: receiving a dielectric substrate having a first conductive layer on a first side of the dielectric substrate and having a second conductive layer on a second side of the dielectric substrate, wherein the dielectric substrate is made of a base material and fiber glass material and the base material and the fiber glass material are continuous from the first side of the dielectric substrate to the second side of the dielectric substrate; forming a plurality of through substrate hole (TSH) openings passing through the first conductive layer, passing through the dielectric substrate, and passing through the second conductive layer; forming a seed conductive layer on sidewalls of the TSH openings; forming a main conductive layer to cover the seed conductive layer and to cover the first conductive layer and the second conductive layer; after the main conductive layer is formed, selectively removing the first conductive layer from the first side of the dielectric substrate and selectively removing the second conductive layer from the second side of the dielectric substrate while leaving the seed conductive layer and main conductive layer along the sidewalls of the TSH openings; forming a central die opening laterally surrounded by the plurality of TSH openings and whose width is greater than a width of each TSH opening of the plurality of TSH openings; arranging a first substrate comprising a first plurality of connectors proximate to the first side of the dielectric substrate; arranging a second substrate comprising a second plurality of connectors proximate to the second side of the dielectric substrate, the dielectric substrate separating the first substrate from the second substrate; forming a passivation layer on the second substrate, the passivat
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript presents a manufacturing method for an interposer frame. It begins with a continuous fiberglass-reinforced dielectric substrate carrying conductive layers on both sides, forms through-substrate-hole (TSH) openings, deposits seed and main conductive layers on the TSH sidewalls, selectively removes the outer conductive layers while retaining the sidewall conductors, creates a central die cavity, bonds connector-bearing substrates to both faces, and deposits a passivation layer on one side.
Significance. If the sequence can be executed without delamination or loss of sidewall continuity, the approach would constitute a plausible variant of plated-through-hole interposer fabrication. Absent any process parameters, yield data, reliability results, or comparison with existing art, however, the practical or commercial significance cannot be evaluated from the supplied text.
minor comments (3)
- [Abstract] The abstract is truncated mid-word ('the passivat'), leaving the final process step incomplete.
- [Abstract] No numerical values (layer thicknesses, plating chemistries, etch selectivities, or thermal budgets) or verification data are supplied, which prevents assessment of whether the selective removal step truly preserves sidewall conductors without damaging the fiberglass matrix.
- [Abstract] The text contains no figures, cross-sectional diagrams, or embodiment examples, making it impossible to confirm the geometric relationships asserted (e.g., TSH diameter versus central cavity width).
Simulated Author's Rebuttal
We thank the referee for reviewing our patent application describing a method for manufacturing an interposer frame with metal-lined through-substrate holes. The document is a patent specification whose purpose is to disclose a novel process sequence; it is not a research article containing experimental results. Below we address the referee's observations on practical significance and the absence of process data.
read point-by-point responses
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Referee: Absent any process parameters, yield data, reliability results, or comparison with existing art, the practical or commercial significance cannot be evaluated from the supplied text. If the sequence can be executed without delamination or loss of sidewall continuity, the approach would constitute a plausible variant of plated-through-hole interposer fabrication.
Authors: We agree that the manuscript, being a patent application, does not contain empirical yield or reliability data; such data are generated during process development and are outside the scope of a patent disclosure. The full patent specification includes a background section that distinguishes the claimed sequence from prior plated-through-hole and interposer methods, particularly the use of a continuous fiberglass-reinforced core that remains unbroken from one face to the other. The process is deliberately ordered so that the seed and main conductive layers are deposited on the TSH sidewalls before the outer copper foils are removed, thereby preserving sidewall continuity and minimizing the risk of delamination at the dielectric-conductor interface. A skilled practitioner can therefore implement the method from the written description without additional experimental results being supplied in the patent itself. revision: no
Circularity Check
No circularity: pure descriptive manufacturing process with no derivations or fitted predictions
full rationale
The supplied text is a patent abstract reciting a sequence of fabrication steps for an interposer frame (receive continuous fiberglass-reinforced laminate with outer copper, drill TSHs, seed+plate sidewalls and outer surfaces, selectively etch outer copper while preserving plated sidewalls, form central cavity, bond dual substrates, apply passivation). No equations, parameters, predictions, first-principles derivations, or self-citations appear. Each step is an independent manufacturing operation; none is defined in terms of a later result or obtained by fitting a quantity that is then re-used as a 'prediction.' The fiberglass-continuity property is an input material fact, not a derived output. Consequently the derivation chain is empty and the circularity score is zero.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Standard drilling, plating, and etching steps can be performed sequentially on a continuous fiberglass dielectric without inducing delamination or plating defects.
discussion (0)
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