PQ Material Sciences Guide — How Each Room's Materials Are Tested Over Time¶

One-sentence summary: every room in the cell (Fusion, Health, Lithography) deals with real materials — plasma, biological molecules, silicon wafers — and the Performance Qualification stage tests how each material behaves across many runs, not just one.

Why this page exists¶

The qualification stack has four stages: IQ (installed), OQ (operates), PQ (performs), MQ (constitutional). PQ — Performance Qualification — is the one that tests behavior over time and under load. It is the stage that asks: "yes, this thing worked once, but does it work consistently?"

Different rooms in the cell touch different materials. Different materials need different performance envelopes. This page is the index of how PQ tests material science across the cell's domains.

If you haven't yet read GAMP5 Test Authority, start there.

Fusion — plasma confinement materials¶

Tungsten divertor erosion¶

Inside a tokamak, plasma at 150 million Celsius touches a divertor — the part of the reactor that absorbs the exhaust. Divertors are typically made of tungsten, the metal with the highest melting point (3,422 °C). Even tungsten erodes under plasma load. PQ measures:

Erosion rate (nm/hour) — is the divertor surviving the design lifetime?
Sputter yield — how many tungsten atoms come off per plasma ion impact?
Recrystallization — is the surface microstructure stable?

The PQ envelope is: erosion rate < 5 nm/hour at design power, sputter yield < threshold, no recrystallization within the first 1,000 hours.

PFC (plasma-facing component) thermal limits¶

The first wall of the reactor takes neutron flux and thermal load. PQ measures:

Thermal cycling fatigue — how many heat-cool cycles before cracks form.
Neutron damage (dpa) — displacements per atom from the neutron flux.
Tritium retention — radioactive tritium absorbed into the wall.

Where to find these tests in the substrate¶

SELECT * FROM c4_validation_receipts
  WHERE validation_id LIKE 'PQ-FUSION-MATERIALS%'
  ORDER BY booted_at_iso;

Health — biological materials and pharmacology¶

Peptide stability¶

The HEALTH-AML protocol uses peptide-based interventions. Peptides are short proteins, and proteins degrade. PQ measures:

Half-life in serum — how long before half is broken down.
Aggregation rate — does the peptide clump (loses function).
Storage stability — degradation at 4 °C vs. -80 °C vs. lyophilized.

CYP routing¶

Most drugs are metabolized by the liver's cytochrome P450 enzymes (CYP). PQ measures:

CYP3A4 / CYP2D6 binding — which enzyme handles the protocol's molecules.
Drug-drug interaction risk — does the protocol block another patient's medication.
Inter-patient variability — do CYP3A4 polymorphisms change the dose?

Frequency targeting tolerance¶

The TB and inflammation protocols use frequency rather than chemistry. PQ measures:

Frequency drift — does the resonance target shift in different patient populations?
Off-target resonance — does the frequency hit anything it shouldn't?
Dose-response stability — does doubling the exposure double the effect?

Where to find these tests in the substrate¶

SELECT * FROM c4_validation_receipts
  WHERE validation_id LIKE 'PQ-HEALTH-MATERIALS%'
  ORDER BY booted_at_iso;

See also: Health Protocol Catalog and GaiaFTCL Health Mac Cell Wiki.

Lithography — silicon and photoresist materials¶

Si wafer flatness¶

A 300 mm silicon wafer has to be flat to within a few nanometers across its entire surface. PQ measures:

Total thickness variation (TTV) — high points vs. low points across the wafer.
Bow and warp — overall curvature.
Surface roughness (RMS) — atomic-scale smoothness.

Photoresist response¶

The chemical layer that gets exposed by EUV light has to react predictably. PQ measures:

Sensitivity (mJ/cm²) — how much light energy is needed.
Resolution (nm) — smallest feature it can hold.
Line-edge roughness (LER) — how clean the edges of patterned lines are.

ASML optics — EUV mirror reflectivity¶

EUV light cannot pass through glass. Lithography uses mirrors — multilayer molybdenum/silicon stacks. PQ measures:

Reflectivity at 13.5 nm — typically 60-70% per mirror.
Contamination accumulation — carbon and oxygen buildup over hours.
Thermal stability — does the mirror figure shift under 250 W beam load?

Where to find these tests in the substrate¶

SELECT * FROM c4_validation_receipts
  WHERE validation_id LIKE 'PQ-LITHO-MATERIALS%'
  ORDER BY booted_at_iso;

What's the same across all three domains¶

A few principles hold across Fusion, Health, and Lithography materials PQ:

PENDING_OBSERVATION is the default. A materials PQ test does not pass on a single boot. It waits for accumulated data. For most, the threshold is at least 30 measurements across at least 7 days.
Drift is the enemy. PQ is more about stability over time than correctness once. A material that performs at spec on day 1 and at 70% of spec on day 30 has failed PQ even though every individual measurement was "correct."
Each test ID is unique per (domain, material, property). The PQ catalog grows over time as the cell's domain coverage expands.
Refusal is information. A REFUSED PQ test is not a failure — it is the cell saying "I cannot make this performance claim with the data I have." That refusal itself is signed and recorded.

How operators use this page¶

If you are working in materials science and want to use the cell to qualify your own materials:

Identify which domain your material fits — Fusion, Health, or Lithography.
Read the relevant catalog page for that domain.
Look at the PQ test IDs in that domain's substrate query.
Set up your measurements to land in the substrate via NATS subjects (e.g., gaiaftcl.pq.materials.fusion.divertor_erosion).
Run for at least 30 days.
Read the PQ rollup — PENDING_OBSERVATION → CURE → CALORIE as the data accumulates.

The cell's job is to keep score, not to do the measurements for you. The cell's value is in the audit trail it produces.

PQ Material Sciences Guide — How Each Room's Materials Are Tested Over Time¶

Why this page exists¶

Fusion — plasma confinement materials¶

Tungsten divertor erosion¶

PFC (plasma-facing component) thermal limits¶

Where to find these tests in the substrate¶

Health — biological materials and pharmacology¶

Peptide stability¶

CYP routing¶

Frequency targeting tolerance¶

Where to find these tests in the substrate¶

Lithography — silicon and photoresist materials¶

Si wafer flatness¶

Photoresist response¶

ASML optics — EUV mirror reflectivity¶

Where to find these tests in the substrate¶

What's the same across all three domains¶

How operators use this page¶

See also¶