by Debra Vogler, senior technical editor, Solid State Technology

June 8, 2009 – As IMEC completed preparations for its 25th anniversary celebration, SST spoke with Luc Van den hove about the research center’s strategy and the keys to its success over the years. On June 2, Van den hove was named IMEC’s president & CEO.

Reflecting on key factors to IMEC’s success, Van den hove noted that one factor is the consortium’s neutrality. “We’re located in a small neutral country, and we’re not dominated by one company — we are truly neutral,” he explained. “We get support from the local government, but it never pressures us to work with a company, or give preferential treatment.” He noted the Belgian government’s position is that for IMEC to be the number one R&D provider, it has to go out and work with the best, wherever they are located, and “that has been a very important reason for our success.”

Van den hove also believes that IMEC’s R&D model is economical for its members because members share the costs (with several partners participating in a program), but the benefits are also shared, and this customer-focused responsiveness is a key performance criteria. “We have also built in enough flexibility so that for partners who want to do proprietary work, they do not have to share that,” said Van den hove. “We adapt our offering to what’s needed by each partner — it’s not a take it or leave it model — we try to bring value to each of the partners.”

IMEC will continue its path to aggressively scaled CMOS technology, focusing on 22nm today, as well as developing the modules and materials that will be needed for the 15/16nm nodes. “These activities will go on for at least the next 10 years,” said Van den hove, “and they will remain an important pillar of our strategy.” Besides memory technology’s need for aggressive scaling, logic technology will need new materials, particularly extreme high-mobility materials, and both technologies will need advanced lithography and 3D integration, he said.

The consortium’s advanced lithography program is focused on developing more cost-effective double-patterning immersion lithography and EUV. “The nice part about EUV is that you can work with much higher k factors, a regime where lithographers are used to working,” he explained. Recognizing that the major challenge with EUV is cost-of-ownership — and the source throughput in particular –Van den hove said that IMEC is still very optimistic about EUV, calling it “the only technology that shows strong potential for implementation for large volume manufacturing for sub-22nm technologies.”

The second pillar of IMEC’s strategy is the expansion of activities into fields that are not directly related to aggressive scaling technology, but which reuse the basic technology IMEC has been developing in its core CMOS program. Van den hove noted that the only way to continue to get out of a downturn is to invest in innovation. “Companies will have to do R&D in the most cost-effective way, and we believe we have set up a model that has been very successful to tackle those R&D challenges,” he said. “So we are setting up plans to continue where we are strong and expand into new areas such as biomedical — where silicon-based nanotechnology can essentially be reused — and photovoltaics (PV), as well as other areas, to secure our success in the future.” In just the past few days, aligned to its 25th anniversary celebrations, IMEC has followed through with two announcements along these themes:

• A Neuroelectronics Research Flanders (NERF), a research initiative with Flanders’ life science institute VIB and the Leuven University, housed on the IMEC campus, supported by a €3M research grant from the Flemish Government for the first three years. Kicking off in October with a roadmap, NERF aims to examine the functional mapping of the brain, generate research methodologies and technologies for medical applications, such as diagnostics and treatment of disorders of the central and peripheral nervous system.
• Joint work with Schott Solar, to explore and develop wafer-based bulk silicon solar cells: thinning the active layer from 150μm to 40μm, introducing alternative back-side dielectric stacks and interdigitated back-side contacts using a passivated emitter and rear local (PERL) back surface field, and exploring cell module integration and reliability. Epitaxial thin-film (<20μm) silicon solar cells on low-cost silicon carrier also will be explored.

Van den hove pointed out that the origin of IMEC’s PV research was work done at the Katholieke Universiteit (K.U.) Leuven — IMEC was a spin-off from there, and PV research was a major part of the work done by the university team that eventually formed IMEC. “In the ’80s and ’90s, IMEC’s PV program didn’t get much attention,” Van den hove noted, but during the last five years attention has increased. “We kept working on solar cell technology for 25 years, continuing to support the program started in the university.” Although the program investigates several routes to PV, it is focused primarily on crystalline silicon (c-Si) PV. “We believe it’s the most promising technology, one of the only technologies that has demonstrated solar cells with lifetimes greater than 20 years and high-efficiency cells.” Now, the challenge is to reduce their cost by more than a factor of 4 in the next 10-15 years, he said. “We have a roadmap to achieve this by reducing silicon consumption (by thinning down the silicon substrate) while maintaining or slightly improving the efficiency of the cells.” Cell efficiency improvements will be addressed by tackling the processing steps, i.e., adjusting diffusions and contact schemes, and generally optimizing the process itself.

The other important PV program at IMEC is organic solar cells, which Van den hove explained have the advantage of being made out of very thin films (the absorption coefficient of organic material is very high), but with the challenges of lower efficiency and limited lifetime that need to be addressed. He estimates that this longer-term R&D work will require about 10-15 years before it can be used for high-volume PV fabrication. In the short term, though, organic PV can be used for consumer applications that don’t require a 20-year lifetime, such as integrated into clothing, or on tents, or where you need flexibility of the material. “These could be nice niche applications in the shorter term for organic solar cells,” he pointed out.

Another major R&D effort at IMEC is in the area of biomedical applications in which nanoelectronics and nanotechnology are used. Examples include functionalized nanoparticles for molecular imaging and curing cancers. “There are also activities for brain/computer interface, such as neuron on chip,” said Van den hove — activities that SST highlighted back in 2005. Research includes measuring signals in neurons and stimulating neurons, “which we think will give us a better understanding of how the brain works,” he said — “and that can be done making devices based on silicon technology. So we are reusing technologies we developed in core CMOS for applications in the biomedical field.” — D.V.