What are the most common cleanroom classification scales?
What are the global cleanroom classification bodies or cleanroom classification scales. We are looking to build several nanofab facilities across 3 continents and are researching the different types of cleanroom classifications that might be possible.
There are two different classification scales that are generally used, the U.S. General Service Administration standards (FS209E) and International Standards Organization (ISO) classifications. The classes are determined by the maximum acceptable numbers of particles (by size) in the air per cubic meter.
In semiconductor manufacturing, wafer fab processes usually require a sub-Class 1 to Class 10 cleanroom, while assembly processes prior to encapsulation of the die require a Class 10K cleanroom. A class 100K cleanroom is all that post-encapsulation assembly and test processes typically require.
Table 1. Cleanroom Classes
|Class Name||0.1 micron||0.2 micron||0.3 micron||0.5 micron||5 micron|