Characterization of sub-10 nm filter cleanliness by electrophoretic purification and analysis

The cleanliness and particle removal requirements on filtration for the semiconductor industry continue to increase in order to keep pace with the development of sub-10nm devices. However, there has been a lack of available instrumentation to directly measure the particles and low levels of "killer" defects that are detrimental to final device function. To address this issue, an electrophoretic particle capture device has been used in order to test its ability to capture and characterize sub-10 nm particles. Using an electrode, a variable electric field is applied to a process stream that results in the capture and subsequent release of particles. The release of particle creates a measurable current that can be correlated to the amount of contamination in a system. In this case we apply the technique to the evaluation of a cleaning method for next generation filtration products developed specifically for the microelectronics industry. We are able to demonstrate that the cleaning method used has a significant impact on the cleanliness of the filter and that the new technique has the ability to effectively characterize its state of cleanliness.