HAMBURG, GERMANY—Enthusiasm continued to reverberate from within the solar industry equipment supply chain as tool suppliers and laser manufacturers descended upon Hamburg, Germany for the 24th European Photovoltaic Solar Energy Conference and Exhibition (known as EUPVSEC; www.photovoltaic-conference.org) from September 21–24. As the highest profile technical photovoltaic (PV) meeting of the year, EUPVSEC has traditionally been the place to assess industry perceptions, to review manufacturing trends, and to measure their impact on production equipment demand. The meeting did not disappoint! And for almost for the first time, the role of laser-based tooling within solar-cell and -panel manufacturing became a topic for discussion amongst market analysts, cell makers, and production line suppliers (see also www.laserfocusworld.com/articles/359809).
At previous EUPVSEC meetings, laser-based tools had been confined mainly to thin-film patterning, with a handful of laser suppliers and integrators promoting similar tool variants. Then, the pull was from venture-capital investment into thin-film panel start-ups, combined with high-profile marketing from leading flat-panel equipment suppliers offering turn-key thin-film production lines. During the week of September 21st, however, this compartmentalized perception of laser tooling within the solar industry was well and truly destroyed!
Driving this equipment inflection sea-change are several new crystalline-silicon (c-Si) cell concepts, previously championed with vigor from the solar research community. Within most novel c-Si cell types are new process stages that help push average efficiencies from 14–16% to 18–20% and above. Laser-based tooling is essential to these cells being realized. Capturing this best from both exhibition and conference attendees was the phrase “selective emitter”—a type of cell design being primed for production roll-out that is enabled—not merely assisted—by laser-based c-Si production tools. Selective emitters feature different phosphorous diffusion levels below and between the metal contacts located on the front surface of the cells. This increases current collection at the contacts and minimizes recombination losses between them.
At EUPVSEC, equipment manufacturers and turn-key line suppliers were actively using the phrase “laser-based” as a marketing ploy; a sure sign that lasers have a bright future within both c-Si and thin-film solar-cell production. Final confirmation will come from the rate to which existing cell lines are upgraded and new capacity added specifically for selective-emitter cell production. Watch out then for “made using lasers” becoming a differentiating tool feature throughout the value chain!
—Finlay Colville, director of marketing, solar Coherent