Brussels (Belgium), September 24, 2018 — At EU PVSEC conference, imec - the world-leading research and innovation hub in nanoelectronics, energy and digital technology and partner in EnergyVille - announced that its latest generation of large-area monofacial screen-printed rear-emitter nPERT cells feature a conversion efficiency of 23.03 percent, certified by Fraunhofer ISE CalLab. The nPERT (n-type Passivated Emitter and Rear Totally diffused) solar cells are made using an industry-compatible screen-printing process that has been designed as an upgrade of conventional pPERC (p-type Passivated Emitter and Rear Cell) processes. According to imec, its nPERT technology is projected to reach 23.5 percent efficiency by the end of this year, and there is a clear technology roadmap to eventually surpass 24 percent.
While p-type PERC solar cells are becoming mainstream in the PV industry, n-type PERT technology is being developed as a cost-effective contender that has a number of inherent advantages: Due to the absence of B-O complexes, n-type cells don’t suffer from light induced degradation (LID) and are less sensitive to metal impurities. That makes for cells that have the potential for a longer-term stability and a higher efficiency. Imec fabricated the M2-sized cells (area: 244.3 cm²) on its pilot line with industry-compatible tools and recipes, in a process that is an upgrade of the pPERC fabrication process, using a similar layout of an n+ region (Front Surface Field) on the illuminated side and a p+ region (as rear emitter) on the opposite side and adding a cost-effective boron diffusion.
“Until now, nPERT solar technology has not yet found the traction it deserves in the industry,” says Loic Tous, senior researcher at imec. “With these ever-improving results, which we achieved by applying knowledge gained from our bifacial nPERT project, we are now demonstrating the potential of nPERT technology. The advantages in stability and efficiency potential over p-type PERC cells, while using the same equipment with the addition of a Boron diffusion, make this a very promising technology for future manufacturing lines.”
Imec is the world-leading research and innovation hub in nanoelectronics, energy and digital technologies. The combination of our widely acclaimed leadership in microchip technology and profound software and ICT expertise is what makes us unique. By leveraging our world-class infrastructure and local and global ecosystem of partners across a multitude of industries, we create groundbreaking innovation in application domains such as healthcare, smart cities and mobility, logistics and manufacturing, energy and education.
As a trusted partner for companies, start-ups and universities we bring together more than 4,000 brilliant minds from over 85 nationalities. Imec is headquartered in Leuven, Belgium and has distributed R&D groups at a number of Flemish universities, in the Netherlands, Taiwan, USA, China, and offices in India and Japan. In 2017, imec's revenue (P&L) totaled 546 million euro.
Imec is a partner in EnergyVille (www.energyville.be), a collaboration of the Flemish research centers KU Leuven, vito, imec and UHasselt in the field of sustainable energy and intelligent energy systems, as well as in Solliance, a partnership of R&D organizations from the Netherlands, Belgium and Germany working in thin-film photovoltaic solar energy (TFPV).
Further information on imec can be found at www.imec-int.com.