Wafer handling tools

From its onset, the semiconductor industry has relied on fluoropolymers as the material of construction for wet processing equipment, fluid transport systems, and wafer handling tools. Semiconductor manufacturing processes are extremely intolerant of particulate and chemical contamination which can, even in trace amounts, cause severe decreases in yields. Therefore, fluoropolymers purity and resistance to chemical attack have created an important role for plastics in the semicon industry. In the next section, we briefly review the chip manufacturing industry to provide the reader with a more in-depth understanding of the important role that fluoroplastics play in this industry. 

There are a large number of potential sources for particles to fall onto a wafer. Advanced tool design and proper selection of clean room technology can be very effective in reducing or eliminating this type of defect. In addition, it is desirable to eliminate manual intervention. The use of minienvironment around the tools and closed wafer-handling cassettes such as FOUP (front opening unified pod) are proven effective. These types of particles are more frequently seen in small clean rooms where wafers are handled manually. 

Scrubber and wet benches are sometimes used one after the other in the same post-CMP cleaning, but this probably does not represent the most suitable solution. In the near future, the more rational way will be to integrate a scrubber or megasonic bath in the CMP tool to avoid handling wet wafers. 

---