{
  "schema": "semiagora.process-simulation.v1",
  "experiment_id": "SA-PROC-METRO-4PP-SHEETR-001",
  "title": "Four-point probe sheet-resistance map",
  "execution_mode": "precomputed-only",
  "model_boundary": "Educational wafer-map replay for sheet-resistance vocabulary. It is not a calibrated electrical metrology report, tool qualification, or wafer acceptance result.",
  "lesson_route": "/learn/process-metrology",
  "simulation_route": "/simulations/process-four-point-probe-sheet-resistance",
  "measurement_context": {
    "wafer": "100 mm teaching map",
    "method": "four-point probe sheet resistance",
    "map_grid": "5 x 5",
    "units": "ohm_per_square"
  },
  "x_index": [-2, -1, 0, 1, 2],
  "y_index": [-2, -1, 0, 1, 2],
  "sheet_resistance_ohm_sq_map": [
    [52, 51, 50, 51, 52],
    [51, 50, 49, 50, 51],
    [50, 49, 48, 49, 50],
    [51, 50, 49, 50, 51],
    [52, 51, 50, 51, 52]
  ],
  "derived_metrics": {
    "mean_ohm_sq": 50.4,
    "center_ohm_sq": 48,
    "max_ohm_sq": 52,
    "min_ohm_sq": 48,
    "center_to_corner_spread_ohm_sq": 4,
    "half_range_nonuniformity_percent": 3.97
  },
  "methods": [
    "Treat each grid site as a saved sheet-resistance measurement point.",
    "Compute the map mean across all 25 teaching sites.",
    "Compute half-range nonuniformity from max, min, and mean sheet resistance.",
    "Use center-to-corner spread as a fast warning for radial process drift."
  ],
  "limitations": [
    "No probe-spacing correction, edge correction, contact force, temperature coefficient, film-thickness correction, or tool calibration is included.",
    "No qualified metrology, facility procedure, wafer acceptance, process recipe, or production uniformity claim is implied.",
    "Real sheet-resistance review requires raw measurement logs, uncertainty, calibration status, wafer map coordinates, and material context.",
    "This replay is not evidence of a SemiAgora-processed wafer."
  ],
  "sources": [
    {
      "label": "NIST Nanofab 280DI sheet-resistance mapping system",
      "url": "https://www.nist.gov/laboratories/tools-instruments/nanofab-tool-four-dimensions-280di-sheet-resistance-mapping-system",
      "note": "Public NIST tool page describing automated four-point probe sheet-resistance mapping and thin-film uniformity use."
    },
    {
      "label": "NIST sheet-resistance measurement report",
      "url": "https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=5777",
      "note": "Public NIST publication context for sheet-resistance measurement discipline."
    }
  ]
}