Question 1

What is edge exclusion in a die per wafer calculation?

Accepted Answer

Edge exclusion is the ring at the wafer rim, typically 2–5 mm, where dies are not usable because of process non-uniformity and handling. The calculator only counts a die when all four corners fall inside the wafer radius minus the edge exclusion.

Question 2

Why does street width change the die count?

Accepted Answer

The street (scribe lane) is the gap between adjacent dies reserved for the dicing saw. The die pitch is die size plus street width, so a wider street means fewer dies fit across the wafer diameter.

Question 3

How many more dies fit on a 300 mm wafer than a 200 mm wafer?

Accepted Answer

A 300 mm wafer has 2.25× the area of a 200 mm wafer, and because edge loss is proportionally smaller on the larger wafer, the usable die count is usually 2.3–2.5× higher for the same die size.

Die Per Wafer Calculator

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