Equation 5 · Part 2 · Advanced Semiconductor Fabrication in Practice: An Advanced Technical Guide
subscript
subscript
What this part means
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
Its job in the formula
A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.
Full expression→subscript→Article meaning
The passage around this formula
This Poisson form is known to be pessimistic in practice, because real defects cluster rather than distributing independently across the wafer — a particle-contamination event or a localized etch non-uniformity produces several nearby failures at once, not one failure drawn independently from a uniform background. Models that account for clustering (the negative binomial family, of which Murphy’s model is a well-known special case) generally predict a higher yield than the naive Poisson formula for the same nominal defect density, because clustering means large stretches of the wafer are defect-free even at a defect density that would look damaging if it were spread evenly. Which model…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
Open the illustrated subscripts: which member of a family? guide →
Sources cited in the article section
These citations provide research context; check each source for the exact claim it supports.