This article discusses the widespread use of PFA in electronics manufacturing, particularly in semiconductor manufacturing. We provide details on contamination routes, regulated pressures, detection methods, and new strategies for phase-out and lifecycle management.
The role of PFAS (1 and polyfluoroalkyl substances) in the electronics sector is extensively scrutinized. Unique chemical properties such as high thermal stability, chemical inertness and hydrophobicity make them essential in a variety of precision driven processes.
However, growing environmental sustainability, bioaccumulation behavior, and regulatory attention has led to the manufacturing of electronic devices tracking, quantifying and reducing their presence across the supply chain.
When PFA is used in electronic manufacturing
Microelectronics uses PFA in multiple process stages, from wafer manufacturing to final device packaging. One of the most important areas is PFA in semiconductor manufacturing, with perfluoroid surfactants formulated in photoresists and reflective coatings. These materials allow for accurate patterning in sub-10 nm shapes.
In the etch phase, a fluorinated process gas is used in a plasma etch reactor. Plasma-based etching provides more accurate control at this stage. These gases promote the etching of highly selective silicon, silicon dioxide and low-K dielectrics. Many of these gases are decomposed into PFA-related by-products during the plasma reaction.
Other PFAS compounds are:
Degreaser and solvents for couher cleaning coolants for ion inpanters and test equipment radiofrequency and 5G circuit wire coatings and PCB laminated dielectric materials, usually PTFE or fluorinated ethylene propylene (FEP).
Due to its low dielectric constant, high fault voltage and low chemical resistance, the functional role of PFA is irreplaceable in many high-speed environments. This makes tracking even more important as phase-outs and replacements approach.
PFAS contamination route
PFAS contamination stems from direct use and secondary reactions. For example, plasma etching can produce volatile fluorinated by-products and can be deposited on reactor walls, gas lines, and removal components. Over time, these residues accumulate, leading to contamination during maintenance, swaps of FAB tools, and even destruction of the HVAC system.
Important contamination vectors include:
Aerial particulates from the plasma chamber used exhausted process gas without a tired liquid waste stream without a suitable scrubber, including rinse solutions and developer bus tool surfaces exposed to repeated PFAS radane processes.
Non-point contamination also occurs. For example, even fluoropolymer seals and gaskets in wet benches and chemical delivery lines can reach ultra pure water (UPW) systems at low levels of PFA. Once these compounds enter a common closed-loop water recycling system with FABS, they are difficult to remove and often require sophisticated oxidation processes, carbon filtration or ion exchange resins.
Tracking and testing
Accurate detection of PFA contamination in electronic environments requires a multi-method approach. Flame ionization detection is insufficient for many low volatile PFAS compounds. Instead, the lab relies on:
Liquid chromatography mass spectroscopy (LC-MS/MS) to identify ultra-traced PFAs in water and solvent solvent combustion ion chromatography (CIC) for the measurement of total organic fluoride (TOF) of water and solvent matrixes, for the determination of GC/MS of total organic fluoride (TOF) of water and solvent matrixes, measures the thermal desorption GC/MS of solid phase materials such as wafers, resins, and resins.
Since many electronic manufacturers operate in multi-layer supply chains, third-party inputs can undermine material traceability. Packaging foam, adhesives and transport materials can all be unexpected PFA sources.
To address this, some industry leaders are requesting full fluoride disclosure from their suppliers and creating an in-house PFAS inventory that tracks usage between chemicals, equipment and environmental outputs.
PFAS regulations and their impact
Regulatory pressures are increasing. The proposed EU reach restrictions submitted by five member states in 2023 could eliminate thousands of PFAS compounds within the next decade. These include short-chain PFAs, which are often assumed to be safer despite new evidence of similar toxicity and persistence.
US PFAS regulations are increasingly enforced at federal and state levels. The US EPA has added over 100 PFAs to its Toxic Release Inventory (TRI). The organization is also finalizing regulations under the Safe Drinking Water Act, which requires reporting and mitigation in water systems that exceed levels above the four PPTs of PFOA and PFOS.
Several states, including Washington and New York, independently prohibit the use of certain PFAs in packaging electronic devices and flame retardants. Failure to comply with these evolving regulations increases the risk of closures, fires and elimination from global markets increasingly managed by sustainability metrics.
Strategic changes in PFA management across electronics manufacturing
The electronics industry is responding to the increasing risks and scrutiny surrounding PFA by making targeted changes across materials, equipment and process designs. One main focus is alternatives such as estrido oil and synthetic waxes.
Manufacturers are actively testing fluorine-free photoresists, surfactants and etchants that can replicate the performance of PFAS-based materials without the same environmental concerns. Manufacturers are investigating these alternatives in wet etching, cleaning and lithographic steps where PFA is commonly used to control surface tension and to promote uniform film formation.
The design team is modifying the process flow to minimize pyrolysis of materials containing PFA. By reducing exposure to high-energy plasma or heat-intensive annealing steps, Fab can reduce the formation of sustained by-products. Equipment suppliers are working closely to introduce new deposition and etch systems with better containment and exhaust treatment capabilities to capture or destroy wastewater containing PFAS before entering a wider waste stream.
In parallel with material and equipment changes, companies are investing in a wider range of pollution control and traceability infrastructure. This includes a point-of-use gas reduction system with enhanced fluorine capture rates and a sealed chemical delivery loop. There is also the promotion of wastewater monitoring and treatment, but it is not legally necessary at this time. Some fabs implement end-to-end PFAS traceability protocols using digital tools that integrate supplier disclosure and emission monitoring into a unique compliance framework.
Even at the organizational level, shifts are ongoing. Companies have embedded PFAS accountability into ESG goals, R&D roadmap and supplier scorecards. As PFAS regulations evolve, compliance is a key component of long-term operational resilience and brand trust, especially in the US, EU and Asia.
PFA is a challenge in equipment recycling and decommissioning
When FABS upgraded to a new process node and abolished the aging device, management of PFAS residues embedded in the deprecated tool occurred. Vacuum pumps, exhaust lines, process chambers, especially those used in dry etching and CVD – contain residual fluorinated compounds that last even after standard decontamination procedures. These residues complicate resale, renovation and disposal, especially if the device crosses international borders, especially if PFA regulations are different.
In some regions, ingredients containing inappropriately treated PFA may be classified as hazardous waste that requires specialized transport and treatment. Furthermore, washing of solvents used during abolition could potentially mobilize PFA to wastewater if not properly captured.
As a result, equipment OEMs and FABs are beginning to develop PFAS-specific decontamination protocols, seeking shared end-of-life management standards. Addressing these often overlooked lifecycle stages is critical to achieving true PFA accountability beyond clean rooms and beyond the secondary equipment market.
Moving from passive management to active removal
The electronics industry can no longer afford to treat PFA as a necessary evil. Their sustained use between gases, resins, coatings and adhesives has created a risk profile where diffusion can be measurable. It affects environmental compliance, product quality and worker safety.
The path that advances requires technical accuracy, intentional alternatives, and system-level transparency.
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