High Purity Lining Solutions for Handling Caustic Piranha Solutions

As the semiconductor industry continues its quest for smaller, faster and more powerful electronic devices, there is a secret sauce that aids this pursuit: a corrosion concoction known as “Piranha” solution. This powerful combination of sulfuric acid and hydrogen peroxide is critical in removing residual organic particles from substrates, a necessary step in high-performance electronics production. However, the properties that make the Piranha solution so effective also make it a substance requiring special handling.

Safe handling of high purity chemicals

The Piranha solution’s corrosive nature and reactivity demand the utmost care in its transportation, processing and storage. The semiconductor industry’s need for ultra-high purity processing standards further complicates this challenge. Any contamination, no matter how minute, can compromise the integrity of the final chip or wafer. This is where the importance of proper containment and handling procedures comes into play.

Companies that need to safely transport, process and store high purity sulfuric acid and hydrogen peroxide and Piranha solution components typically rely on steel tankers, trailers, storage tanks, process vessels and ISO (international intermodal) containers lined with PFA (perfluoroalkoxy), the most chemically inert fluoropolymer lining. The metal surfaces alone cannot withstand the aggressive nature of these chemicals without yielding to their corrosive properties. A fluoropolymer lining can supply a dual purpose to both protect the contents and prolong the lifespan of the container.

Fluoropolymer linings secure high purity chemicals

PFA as a chemically inert fluoropolymer is exceptionally resistant to a wide range of chemicals. This includes strong acids and oxidizers, making it an ideal material to help contain Piranha solutions and other aggressive chemicals. No other resin can match PFA’s ability to protect against contamination while maintaining the purity of the acids that comprise the Piranha mixture.

• The benefits of PFA extend beyond its chemical resistance.
• Its high-temperature tolerance (up to about 260°C) is beneficial when dealing with exothermic reactions associated with Piranha solution.
• PFA also has a smooth, non-stick surface that prevents chemical residues from adhering to container walls, facilitating easier cleaning and reducing the risk of cross-contamination.
• PFA’s low permeability helps prevent chemicals from diffusing through the lining, further ensuring the integrity of the contained substances.

Trusted expertise in applying and welding high purity linings

Electro Chemical Manufacturing (ECM) applies and welds PFA sheets to line tank, trailer and ISO container interiors. The process demands greater technical skill and commitment to maintaining ultra-clean conditions that what is found by tank lining companies serving the semiconductor industry.

When welding, other companies only deploy a clean room “tent” over the manway. Tents are vulnerable to seal-breaking and contaminant influx.

In contrast, ECM has invested in a fully equipped Class 10,000 clean room, large enough to house dedicated clean equipment and a complete ISO container for liner installation. This infrastructure investment and expertise level helps set ECM apart as a leading provider in high-purity chemical containment, such as for Piranha storage or handling.

As the semiconductor industry continues to grow and push the boundaries of technology, it requires manufacturing partners that understand the importance of safe handling for aggressive chemicals like Piranha solution while adhering to purity standards. ECM created the processing conditions and supplies the technical expertise to apply and weld PFA linings for industries that require pure, secure containment. This degree of dedication to quality and reliability for its lining services ensures aggressive chemicals such as these can be transported, processed and stored without compromising standards.

One of ECM’s transportation services clients has had a Halar®-lined trailer in service for 4 years now, and the liner looks as good as it was when it was first installed. For details about their experience, check out the case study Halar®, Sulfuric Acid Hauling and Semiconductors.