ConceptStatus: FOUNDATIONALUpdated 2026-08-13

Semiconductor Metrology and Defect Inspection

How fabs measure dimensions, overlay, films, composition, defects, and electrical behavior without confusing measurement with process control.

Definition

Metrology quantifies specified properties, while inspection searches for anomalies or defects; together they provide the evidence used to control processes, disposition wafers, and learn yield.

Process position

Inputs

  • Wafer, reticle, die, or package
  • Sampling plan
  • Measurement recipe
  • Reference and calibration data

Outputs

  • Measurements and defect maps
  • Statistical signals
  • Disposition and root-cause evidence

How it works

  1. 01Define the measurand or defect class
  2. 02Calibrate the system
  3. 03Select sites and sampling frequency
  4. 04Acquire data
  5. 05Classify and correlate signals
  6. 06Feed results to process and yield control

Measurement answers a defined question

A useful control plan states what property matters, where and how often it is sampled, how uncertainty compares with the process window, and what action follows an excursion. More data is not automatically better control.

Source-supported[1]

Semiconductor process control relies on inspection, metrology, and data analysis across reticle, wafer, and packaging operations.

Inspection and review form a learning loop

High-throughput inspection finds candidate anomalies; review and classification determine which signals represent meaningful defect mechanisms. Correlation with process history and electrical yield turns those observations into root-cause evidence.

Source-supported[2][1]

Inspection and metrology data can be combined with analysis to identify defect sources and support yield improvement.

Sources

Citations support the tagged claims above. Access dates record when Maha Strategies last checked the public source.

  1. [1]Annual Report: Process Control and Yield Management · KLA · 2024 · accessed 2026-08-13
  2. [2]Annual Report: Inspection, Metrology, and Yield Analysis · KLA · 2019 · accessed 2026-08-13

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