Cleanliness Verification

Each year the need for stricter cleanliness levels for cleaned parts is discovered. One professional may work in the semiconductor industry, where critical dimensions are shrinking every hour, or so it seems. Another professional may work in the automotive industry, where it is being learned that the initial operation of an engine will determine its life expectancy.

In all cases, the tolerable level of contamination is constantly decreasing. The problem is, how to measure this contamination? With the exception of the semiconductor wafer, most contamination sensitive parts are complex in shape and therefore do not lend themselves to traditional scanning techniques; therefore, different methods need to be used when testing these items. Let’s take a look at the three more common techniques currently used and discuss the advantages, disadvantages and benefits of each.