IC Knowledge - Cleanroom Cleanliness

Cleanroom cleanliness guidelines

Introduction
A common question when considering a cleanroom is how clean does the cleanroom needs to be for a specific use being planned? The exact cleanliness requirements depend on many factors including the processes being run, products being produced and even the specifics of die sizes and layouts. So specific requirements are dependent on many detail but some general guidelines are possible.

General guidelines
The following table presents some general guidelines for cleanroom cleanliness for semiconductor and MEMS applications. This table is taken from the IC Knowledge – Cleanroom Reference Guide for Semiconductor and MEMS applications.

Table 1. Cleanroom Cleanliness Recomendations.

Cleanroom Class

Semiconductor linewidth

MEMS linewidth

ISO Class 7

Wafer sort and packaging areas

>4.0 microns

ISO Class 6

> 3.0 microns

> 2.0 microns - use Class 5 for photo

ISO Class 5

> 1.5 microns

>1.0 microns

ISO Class 4

>700nm

>500nm

ISO Class 3 >350nm ---

ISO Class 2 >180nm ---

ISO Class 1 >90nm ---

Minienvironments <90nm ---

Table 1 is just one of many summary tables available in the IC Knowledge - Cleanroom Reference Guide for Semiconductor and MEMS Applications Related Products

Cleanroom Reference Guide for Semiconductor and MEMS Applications - combines all of the essential information to design, build and operate a cleanroom into one easy to access concise guide. Published March 2008, 109 pages long, full color, with 122 figures and 61 tables. New Price $500. ORDER NOW!

Cleanroom Class	Semiconductor linewidth	MEMS linewidth
ISO Class 7	Wafer sort and packaging areas	>4.0 microns
ISO Class 6	> 3.0 microns	> 2.0 microns - use Class 5 for photo
ISO Class 5	> 1.5 microns	>1.0 microns
ISO Class 4	>700nm	>500nm
ISO Class 3	>350nm	---
ISO Class 2	>180nm	---
ISO Class 1	>90nm	---
Minienvironments	<90nm	---