This Standard was technically approved by the MEMS/NEMS Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on August 18, 2017. Available at www.semiviews.org and www.semi.org in March 2018; originally published March 2006; previously published August 2012.

This Guide provides a framework for specifying the dimensions, location, quantity and characteristics of alignment targets that are placed on each wafer of a pair of wafers. Such targets are used to align two patterned wafers prior to an operation that bonds them together.

This Guide applies to targets that can be used with two common alignment processes—inner surface alignment and outer surface alignment.

This Guide covers specification requirements, mark characteristics and applications.

SEMI M20 — Practice for Establishing a Wafer Coordinate System