The first thing to record about US20260223625A1 is that its claim 1 is (canceled). The application, published 30 July 2026, assigned to Tokyo Electron Limited and naming Nathan Ip as sole inventor, therefore begins at claim 2. Three claims stand independent: claim 2, claim 10 and claim 18. Everything else depends from one of them, and the published set carries several marks of amendment that were not reconciled afterwards.

The three independents

Claim 2 is the feedforward method. Measure, using a metrology tool integrated with a wafer bonding tool, a physical parameter of a first wafer representing information relating to topographical features; generate, by a tool controller having a model of a wafer bonding process, a first bonding recipe based at least in part on that parameter; bond the first and second wafers accordingly. Two wherein clauses close it: the parameter is at least one of overlay, in-plane distortion, slope, curvature, force or stress, and the metrology tool is at least one of six named instruments.

Claim 10 inverts the order into a feedback method — bond first, measure the resulting post-bond wafer, generate a second recipe from that measurement, bond the next pair accordingly. Its wherein clauses look parallel but are not identical: claim 10's instrument list contains seven options, adding a scanning interferometric sensor that claim 2's six-item list omits. That difference is load-bearing, and claim 15 confirms it by tying the scanning interferometric sensor to measuring topography of the post-bond wafer.

Claim 18 is the broadest in reach and the least like the other two. It recites a method using a plurality of wafer bonding systems, in which a first system measures, generates a recipe, bonds, and transmits at least one of the physical parameter or the recipe to a second bonding system, which bonds in accordance with what it received. Notably, claim 18 recites no instrument list and no parameter list — the limitations that constrain claims 2 and 10 are simply absent. It is bounded by the transmission step and little else.

The method of claim 2, wherein: the physical parameter includes slope, and the metrology tool comprises a Shack-Hartmann sensor configured to measure the slope.— Integrated Metrology for Process Controls in Wafer Bonding System, US20260223625A1

Four irregularities in the dependent structure

First, the wafer ordinals do not run continuously. Claim 2 introduces a first and a second wafer, then bonds "a fifth wafer and a sixth wafer" to produce "a third post-bond wafer" — with no third wafer, no fourth wafer and no second post-bond wafer introduced anywhere in that claim. Claim 10 repeats the pattern, jumping to "a seventh wafer and an eighth wafer" to produce "a fourth post-bond wafer". Third and fourth wafers do exist, but in claims 3, 7, 8 and 9. The natural reading is that limitations were consolidated upward into the independents during amendment and the numbering was left as it stood.

Second, claim 4 depends from the wrong parent. It reads "The method of claim 2, wherein creating the model comprises" and then recites "the physical parameter of the third wafer", "the physical parameter of the fourth wafer", "the process conditions" and "the estimated physical parameter of the simulated post-bond wafer". Every one of those terms — and the step of creating the model itself — is introduced in claim 3, not claim 2. Claim 4 is written as though it depends from claim 3. Claim 5 then depends from claim 4, so the defect propagates into the chain that describes how the recipe is actually generated.

Third, two dependents restate what their base claim already requires. Claim 14 recites that the physical parameter includes at least one of overlay, in-plane distortion, slope, curvature, force or stress — a list already recited in claim 10, from which it depends. Claim 15 recites a scanning interferometric sensor, already present in claim 10's instrument list. Neither narrows claim 10 as published.

Fourth, "PhotoStress" appears inside claims 2 and 10 as a proprietary product designation with no further specification anywhere in the record. Naming a commercial instrument in a claim produces a concrete fallback at the cost of covering only that instrument.

Taken together, these are the fingerprints of a set consolidated during prosecution rather than drafted in one pass. The practical fallback structure is uneven. Claim 2's chain is deep — model creation (claim 3), model use and tuning (claim 5), second-wafer measurement (claim 6), lot framing (claim 7), a bridge into feedback (claims 8 and 9), and instrument-to-parameter pairings (claims 16 and 17). Claim 10's chain is shallower and partly redundant. Claim 18 has three dependents, of which claim 19 supplies the only substantive narrowing — that recipe generation estimates post-bond distortion using a model and the recipe is configured to reduce post-bond distortion of wafers bonded in the second system.

Design-around space follows from where the limitations sit. Against claims 2 and 10 the openings are instrument-shaped: measure a quantity outside the recited six, or use an instrument outside the recited list. Against claim 18 there is far less to work with, because it recites neither list — avoiding it means not transmitting the parameter or the recipe between systems at all.

The standing caveat applies with force here. This is a published application, not an issued patent. It is unenforceable in this form, and a set that opens with a canceled claim, skips ordinals and misroutes a dependency is visibly mid-prosecution. The claims that issue, if any do, should not be assumed to look like these. The one structural feature likely to survive is the split across three control topologies, since feedforward, feedback and multi-tool operation are genuinely different inventions rather than three framings of one.