
106 Semiconductors: Integrated Circuit Design for Manufacturability
For the fourth dimension (i.e., in time or voltage domain) in which the IC
has to operate, design rules should guarantee 100% functionality and reli-
ability within the assumed process variability margin (e.g., 10%). The process
excursions translate into parametric variations, which may be acceptable for
the digital, but too big for analog/RF products (Table3.5). As an example,
variability control of a pattern transfer process requires compensation of
mask CD data based on photo and etch bias extracted as a function of layout
dimensionality (Table3.6):
• 1D: pitch ...