Atmospheric Plasma–Based Surface Cleaning Solutions for Advanced Electronics Manufacturing
ABSTRACT
The continuous scaling and increasing complexity of electronic devices demand advanced surface cleaning technologies that are both highly effective and environmentally sustainable. Atmospheric plasma–based cleaning has emerged as a promising alternative to conventional wet chemical and solvent-based processes for electronics manufacturing. Furthermore, more difficult contamination removal can be accomplished with the new hydroplasma technology.
The atmospheric plasma jet enables localized, non-contact cleaning while maintaining compatibility with sensitive electronic materials. A key advantage of the atmospheric pressure plasma is its dry processing capability, eliminating the need for liquid chemicals. The plasma is generated primarily from air and can be utilized with other gases, resulting in a process free of volatile organic compounds (VOCs) and significantly reducing environmental, health, and safety concerns. For applications requiring enhanced removal of organic residues, hydroplasma operation employs a low volume of water, achieving efficient cleaning with minimal resource consumption.
The following presentation will showcase how this technology effectively removes contaminants encountered in electronics processing with results from various material characterization methods. This includes solvent residues on silicon wafers, metal oxides using forming gas (N2/H2) plasma, and flux residues and epoxy layers through hydroplasma treatment. Removing epoxy bleed-out from die surfaces ensures pristine surfaces which are activated and ready for the application of TIM (Thermal Interface Materials). Ultimately, wettability and thermal surface properties are improved.
The atmospheric plasma jet system supports a wide range of substrate sizes and process requirements, with jet diameters ranging 4 mm to 250 mm for large-area substrates, including 300 mm silicon wafers. Processing speeds range from 50 mm/s to 800 mm/s, with high-precision motion provided by six-axis robotic control, while high-volume manufacturing is enabled through conveyor belt integration. Plasma generation uses compressed air, ensuring simple and cost-effective operation.
Effective surface cleaning is achieved across multiple applications. In this talk, results from several case studies will be presented, including complete removal of IPA and acetone residues from silicon wafers, elimination of copper oxides with thicknesses of up to 100 nm, and thorough cleaning of Au and Ni pads prior to wire bonding.
The fully automated system supports inline integration and repeatable process control, making it suitable for deployment in high-throughput manufacturing environments. Experimental results demonstrate high cleaning efficiency, improved surface activation, and process uniformity across a range of electronics substrates. These findings highlight atmospheric plasma and hydroplasma technologies as sustainable, cost-effective solutions for next-generation electronics surface preparation and contamination control.
BIOGRAPHY
Terry Dunbar is a Global Account Manager for semiconductor applications at Plasmatreat, supporting manufacturers and technology partners in addressing critical surface preparation and cleaning requirements for semiconductor substrates, wafers, and advanced packaging processes. He has more than 26 years of experience in semiconductor-adjacent markets, electronics manufacturing, and advanced process technologies, with an emphasis on translating surface-related challenges into manufacturable solutions.
In his current role, Terry focuses on the application of plasma-based surface modification technologies for wafer and substrate preparation. His work addresses complex interface challenges including organic and inorganic residue removal, polymer and epoxy contamination, metal oxide reduction on contact and bond surfaces, and surface activation prior to bonding, metallization, or interconnect formation. These process approaches are used to improve surface energy control, interfacial cleanliness, adhesion consistency, and reliability while reducing dependency on wet chemical processes.
Prior to joining Plasmatreat, Terry held a range of senior commercial and business development roles at Nordson Corporation, where he supported global customers in precision dispensing, materials processing, and electronics assembly technologies. He has experience working across device manufacturing, advanced packaging, and assembly ecosystems, collaborating with both process engineering and manufacturing teams.
Terry holds a BA in International Business from Southern Illinois University and is an active participant in industry forums focused on semiconductor surface preparation, cleaning, and process integration.