SEMI P24 - CD Metrology Procedures
This standard was technically approved by the Global Micropatterning Committee and is the direct responsibility of the North American Micropatterning Committee. Current edition approved by the North American Regional Standards Committee on July 11, 2004. Initially available at www.semi.org September 2004; to be published November 2004. Originally published in 1994.
NOTICE: This Standard or Safety Guideline has an Inactive Status because the conditions to maintain Current Status have not been met. Inactive Standards or Safety Guidelines are available from SEMI and continue to be valid for use.
The purpose of this document is to establish uniform procedures for metrology systems for the litho-metrology task. It does not address how these systems will be applied to solve problems, nor does it address other contributors to process variations such as thermal wafer processing, exposure tool focus control, materials, etc.
This document discusses determining the performance of gauging/measurement systems for a very specific application—the lithography section of integrated circuit wafer fabrication. This document in many cases, will be applicable to IC mask-making, in which case the word "mask" can be substituted for "wafer."
It is acknowledged that the final measurement for a fabricated wafer is the electrical functionality. However, the intermediate lithographic measurements can be useful in prediction and control of final functionality. This document is intended to be useful for this litho-metrology application, irrespective of the technology employed.
Measurement results and system performance depend on the sample(s) used. Therefore, performance for different systems or the same system at different times can only be appropriately compared when the measurements are obtained with a sample of the same material composition.
The parameter addressed is precision. Additional important parameters are reliability and cleanliness, which have been addressed by other SEMI Standards.
Referenced SEMI Standards
SEMI E10 — Standard for Definition and Measurement of Equipment Reliability, Availability, and Maintainability (RAM)
SEMI P19 — Specification for Metrology Pattern Cells for Integrated Circuit Manufacture