Maximum allowable slip and other non-uniformly
distributed defects are frequently specified when procuring polished and
epitaxial silicon wafers. SEMI M62 specifies a maximum allowable fraction of
the epitaxial wafer surface area that can contain slip.
This Guide provides a design for and
guidance for use of a wafer grid that facilitates the determination of the
fraction of the wafer surface area covered by observed defects.
This Guide defines a grid pattern that
is useful for quantifying surface defects on a nominally circular semiconductor
wafer. The grid is defined such that it contains 1000 elements of approximately
equal area. Each grid element thus contains 0.1% of the total quality area of
the surface being inspected. Defects that are non-uniformly distributed (e.g.,
slip) can be quantified in terms of the percent defective (or percent useful)
area on the wafer surface.
The grid described is referenced to
the center of the wafer. A concept of a ‘fixed quality area’ is used, based on
nominal wafer diameter, such as is specified in SEMI M1.
Referenced SEMI Standards (purchase
separately)
SEMI M1 — Specification for Polished Single
Crystal Silicon Wafers
SEMI M59 — Terminology for Silicon
Technology
SEMI M62 — Specification for Silicon
Epitaxial Wafers
SEMI MF154 — Guide for Identification
of Structures and Contaminants Seen on Specular Silicon Surfaces
SEMI MF1725 — Practice for Analysis of
Crystallographic Perfection of Silicon Ingots
SEMI MF1726 — Practice for Analysis of
Crystallographic Perfection of Silicon Wafers
SEMI MF1809 — Guide for Selection and
Use of Etching Solutions to Delineate Structural Defects in Silicon
Revision History
SEMI M17-1110 (Reapproved 1121)
SEMI M17-1110 (Reapproved 1015)
SEMI M17-1110 (technical revision)
SEMI M17-0704 (technical revision)
SEMI M17-0998 (technical revision)
SEMI M17-90 (first published)