Entegris, Inc. today announced a product extension for its VaporSorb line of airborne molecular contamination (AMC) filters. VaporSorb is a brand of filter used in cleanroom environments and for process tools during key steps in semiconductor manufacturing. VaporSorb filters have been engineered to capture airborne organics, bases and strong acids‹all in one filter. The new VaporSorb TRK has added unique material to allow it to become the first single filter to capture not only the top three core contaminant classes, but also the fourth, a group defined as weak acids.

Designed specifically for photolithography coater/developer tracks, the new filter was created as a “four-in-one” filter solution to avoid the complexities of multi-filter handling and to build on the previous “three-in-one” technology. In addition, the filter retains the VaporSorb’s industry-leading service life to reduce both tool downtime and cost of ownership.

“Today’s photolithography yield concerns can begin to be alleviated by addressing the one potential contaminant class that has to be addressed, and that is weak acids,” stated Senior Product Marketing Manager for Entegris AMC Filtration Services, Joe Wildgoose. “With VaporSorb TRK, we not only have a single solution that addresses the three common major concerns, but also the newest and latest concern regarding weak acidic airborne contaminants.”

Examples of weak acids include acetic and formic acids (acetate; CH3COO- and formate; HCOO-) and nitrous acid (nitrite; NO2-). These contaminants are causing concerns regarding defects and yield in photolithography processing, since they are not removed by traditional AMC filters and, furthermore, may be formed from organic contamination when using traditional filter designs.

VaporSorb filters use a unique mix of materials to capture airborne molecular contaminants. The mix was improved by adding a new adsorbent to create the new four-in-one filter. In-field, end-user testing has confirmed that the filter is capable of capturing all organics, bases, strong acids and weak acids that cause wafer or equipment defects.