UV curing has made significant inroads in the world of printed electronics. The potential for UV curing of printed electronics was among the subjects discussed at uv.eb EAST, a ultraviolet (UV) and electron beam (EB) conference and exhibition which was held Oct. 4-5, 2011 in Syracuse, NY. Talks given by UV equipment manufacturers, university officials and manufacturers all pointed to further opportunities for utilizing UV in printed electronics.

The conference was organized by RadTech, and sponsored by the New York State Energy Research and Development Authority (NYSERDA). NYSERDA also showcased the start-up of the new NYSERDA-funded UV/EB Tech Center in Syracuse. The center, built to accelerate commercialization of the technology, is located at SUNY-ESF (State University of New York-College of Environmental Science and Forestry).

The use of UV in manufacturing of solar cells and displays was the topic of the Electronics Session. In the opening talk, “UV Processing for Electronics,” Kevin Joesel of Fusion UV forecasted 9% average annual growth over two years for UV/EB applications in printed electronics.

In terms of photovoltaics, Joesel noted that UV curing is being used in areas such as photo resist deposition, electronic board conformal coatings, electrical potting materials UV cured protective hard coats, conductive inks and dielectric coatings, as well as cure clear conductive layers, backsheet/film and encapsulation resins.

Dr. Wayne E. Jones, professor and chair, Department of Chemistry, Center for Autonomous Solar Power (CASP), and Center for Advanced Microelectronics Manufacturing (CAMM) at State University of New York (SUNY) - Binghamton, next discussed “Inorganic and Organic Hybrid Solar Cells on Flex: Opportunities and Challenges for UV/EB Technology.” 

After analyzing the opportunities for flexible PV, Dr. Jones discussed work being done on roll-to-roll manufacturing on displays at CAMM and PV at CASP.

Dr. Jones added that CASP is currently focusing it solar efforts on thin-film dye sensitized solar cells (DSSC) and organic cells, using slot die coating, roll-to-roll fabrication and earth abundant materials. He added that UV and EB can help decrease cure time and adhesive thickness.

“UV and EB could be the key for low cost future manufacturing,” Dr. Jones concluded.

Sartomer’s Bill Schaeffer gave the next presentation, on “Energy Curable Materials to Enhance the Exterior Durability of Electronic Handheld Devices.” Schaeffer discussed the trend toward scratch-resistant screens as well as wear resistant casings that house the electronics on cell phones, game systems and other hand-held devices, and presented data on highly functional urethane acrylate oligomers suitable for this application.

John Herold of DELO Industrial Adhesives LLC followed with “Speed Up Your Productivity – UV/Light Curing Adhesives for Bonding of Electronic Components.”

In his talk, Herold noted that DELO has made significant inroads in the smart card, smart label and cell phone markets, and sees opportunities in displays and semiconductors for packaging. He cited numerous advantages of UV curing, including the short curing times, no thermal stress on components and precise control of the curing process. Herold added that bonding with light curing adhesives can replace welding and other thermal joining methods.

“Light-curing adhesives play an important role in electronic manufacturing,” Herold concluded.

The final talk was “Flexible & Printed Electronic Devices Made Roll-to-Roll on Unsupported Substrates,” presented by Dr. Mark Poliks of Endicott Interconnect Technologies, Inc. Working with CAMM at SUNY Binghamton, Endicott Interconnect Technologies is Developing a host of areas, including flexible sensors, medical electronics and capacitors.

Endicott Interconnect is using a variety of production methods, including photolithography; wet and dry processing of flexible, unsupported, thin film-based active, passive electronic devices and advanced interconnect technology; and development of materials and processes for inkjet printed electronics utilizing UV lamps, once again showing the growing opportunities for UV in printed electronics.