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Friday, November 30, 2012

Developments Continue in OPV

Despite the dominance of crystalline silicon products in the market today, significant commercial and research milestones continue to be reached by organic photovoltaics (OPV). Currently, OPV does not offer the efficiency levels or lifetime assurances of crystalline silicon, but OPVs can offer unique form factor advantages, low capital expenditure requirements and low cost roll-to-roll production. At the SEMI Plastic Electronics Conference, held in Dresden Germany from October 9-11, three days of technical and business presentations dedicated to OPV reviewed the status of OPV and the near and long term expectations for the technology.


A highlight of the OPV track at the conference was a keynote presentation by Thibaud Le Séguillon, CEO of Heliatek. The company was founded in 2006 out of two leading universities in Germany and this announced the world’s leading OPV efficiency of 10.7 % and successfully demonstrated R2R production in Dresden. Heliatek is backed by backed by industry (Bosch, BASF, RWE) venture capital (Wellington Partners) and has received €10 M in public funding. The company is in the process of ramping up commercial production with 75MWp capacity and expected to begin a second R2R fab in January 2013.

Heliatek is focused on four key competencies: materials development, stack architecture, roll-to-roll production, and OPV business development. The company’s business development strategy is to provide energy harvesting films for a variety of end markets, not in rooftop panels. The near-term applications are for “energy to go” applications up to 2-3MW, including automotive roofs, but by 2015 they plan to fully exploit the building integrated PV market (BIPV) providing films to glass, cement, polycarbonate, membranes and other building materials. They are targeting markets that need to unique form-factor of flexible films including ease of integration, aesthetics, superior energy harvesting and truly disposable green qualities. A key differentiator for Heliatek OPV—critical to automotive and architectural applications-- is transparency. Today, they achieve 6.5% at 30% light transmission with a near-term goal of 7% at 30% light transmission, then 50%.

The company utilizes small molecule organics—oligomers—rather than polymers to achieve better efficiency, lifetime performance and production reliability. Oligomers do not require solvents in production, enables the preparation of optimized multilayer tandem cells, and avoids interface degradation by adding dedicated (doped) interlayers. The product utilizes a 250 nm stack with absorber layers that requires an amazing 1 gram of material for every square meter. Their Gen 8 production line (2.2M width) has a throughout of one meter per minute.



Le Séguillon confidently explained that only a small shift in spectra (50-100nm) will enable 13% efficiencies. He sees a clear path to 15% efficiencies. The company claims superior energy harvesting, up to 25% higher yield over traditional PV. At low light, Heliatek claims 15-25% better efficiency than other PV technologies and no loss of efficiencies at low temperatures.

Heliatek’s foil-encapsulated solar films withstand lifetime tests well above industry standard PV limits Using IEC testing methods, Heliatek OPV provides excellent lifetime rating, proving > 95 % efficiency after 1,800 hrs both in light soaking test and at 85 °C. Extrapolated light soaking lifetime T80: 13,600 hrs. (approx. 24 yrs.).

The product is manufactured on roll to roll pilot lime using 30 cm wide PET-substrate using linear sources with low temperature vacuum deposition. Laser scribing is used for P1, P2 and P3 structuring. One vacuum rollcoater integrates organic multilayer deposition, metal deposition, P2, P3 and first encapsulation.

3-Day OPV Agenda

The SEMI Plastics Electronics Conference featured morning plenary sessions with 3-afternoon and morning tracks on OPV, Displays and Lighting, and Integrated Systems. Over 15 presentations were given on OPV organized into technology, business case, and manufacturing. In addition to sessions on current and near-term commercialization from Heliatek, Merck Chemicals, Mitsubishi Chemical, Eight19, and Isovoltaic, the latest research on OPV was presented by CEA LITEN, Holst Centre, VTT, and many others.

European Consortia, ASML, Supplier Network Plan for 450mm Transition

European government representatives, consortia and suppliers discussed programs to support and participate in the anticipated conversion of leading edge wafer manufacturing to 450mm wafers at SEMICON Europa in Dresden. Possibly signaling a major change in the 450mm planning framework, representatives from G450C, imec, Fraunhofer IISB, and others discussed mechanisms for greater European participation, and emerging research initiatives, related to 450mm development. In addition, in probably the first major public discussion of the 450mm lithography system schedules following investments from TCMC, Intel and Samsung last summer, ASML provided a comprehensive presentation on their roadmap for 450mm EUV platforms.

Michael Liehr, newly promoted to Executive Vice President of Innovation and Technology at the College of Nanoscale Science and Engineering (former IBM veteran, Paul Ferrar has been appointed General Manager, Vice President and coordinator of G450C project), provided an update on consortium’s pilot fab, tool roadmap, wafer development, and wafer availability plans. Newly announced at Europa was G450C’s welcome of global collaboration efforts with regional consortia and government agencies. As a new consortium on the crowded stage of collaborative research development, G450C’s working relationship with other consortia in the industry has been an ongoing question for manufacturers, suppliers, and key stakeholders. G450C’s role in prequalifying tools for 450 wafer manufacturing places them in a powerful, central role in the future of the industry. With the industry consolidating and global R&D dollars needing increasing focus and efficiency, the roles, core competencies, and optimal distribution of research initiatives across the world is undergoing significant transformation.

“We’re looking forward to working with any regional organizations including wafer pool and adjunct tool demos,” said Liehr during the session. While G450C priority remains on the specific program deliverables, Liehr spoke to the need to recognize and value the contributions of other players in global industry. He said that G450C selection, validation, evaluation of projects would proceed with criteria emphasizing technical and commercial transition value and that “G450C understands that public funding must be applied within the taxpayer region.”

Liehr’s comments were welcome news to European consortia with a high stake in the semiconductor industry. The Fraunhofer-Gesellschaft network in Germany, for example, has 60 institutes, more than 1800 employees and an annual research volume of 1.65 billion euros (2010), of which 1.4 billion euros is generated through contract research. Lothan Pfitzner, head of department at Fraunhofer IISB provided an overview of his organization’s existing and planned activities in 450mm manufacturing process development. Pfitzner said Fraunhofer Group will support 450 mm R&D&I activities based upon their strong expertise and experience in equipment assessment, manufacturing science (e. g. process control, automation, wafer handling, etc.), flying wafer concepts, green aspects, modeling and testing.

For reasons of cost optimization, Fraunhofer is also willing to reclaim 450 mm wafers. In addition, Fraunhofer hopes to contribute in the area BEOL and of TSV in optimization of processes as well as in the area of metrology and defect detection and characterization. Part of these activities will take place at the Fraunhofer IISB Erlangen facilities.

Fraunhofer plays a key role in many current and planned public-funded research efforts related to 450mm manufacturing. The ENIAC EEMI450 is currently developing and evaluating wafer material, metrology tools, process equipment, and handling systems. The CATRENE NGC450 program is providing analysis and optimization of cluster platform performance. Planned programs under Framework 7 include SEA450 involving equipment assessment of cleaning and hot processing equipment and corresponding metrology tools. Another planned program is ENIAC 450EDL project involving virtual metrology and predictive maintenance models for 450 mm metrology tools.

Imec, headquartered in Leuven, Belgium, has nearly 2000 researchers including more than 600 industry residents and guests, is also planning a 450mm pilot line to begin construction in 2013 and scheduled for completion in 2015. Phase one of the program is anticipating funding from the Flemesh government, EU ENIAC FP7, and industry sources. Imec expects to play a key role in the acceleration of 450mm equipment development through installation of alpha and beta tools for early learning in an “industry-relevant technology flow.” The organization’s track record of support for advanced process and lithography development is expected to be a key factor in securing a strong role in 450mm manufacturing programs.

Other European initiatives include those by Israeli “Metro450” Consortium comprised of five key companies: AMIL (metrology division of Applied Materials), Nova, Jordan Valley, Nanomotion, and Intel. University support comes from four institutions and public funding comes from the Israeli Chief Scientist budget. The regional interest in 450mm manufacturing stems from Israel’s strong success in wafer fab metrology, now accounting for over 30% of world’s share and approximately $1.3 billion in sales. Menachim Shoval, Metro450 Board Chair, said the transition of current 300 mm metrology solutions to 450mm manufacturing is not trivial and threatens their current world position.

Other regional interests expressed during the forum include those from the state of Saxony in Germany. Silicon Saxony, the organization representing the interests of the substantial semiconductor cluster, has a vision that “By 2018, Silicon Saxony will be seen as a trendsetter for innovative semiconductor manufacturing technologies for 450mm and may plan to install its 1st 450mm manufacturing site in the Dresden region.”

The scale and diversity of interests in 450mm is impressive, but a realistic forecast for European pilot lines and public funding is hard to gauge. Currently G450C plans to qualify “one or two…maybe three” tools per process, limiting broad supplier participation in future 450mm manufacturing. European efforts to supplement the G450C qualifying process may help open the participation opportunities for other companies in 450mm manufacturing, especially for European companies hoping to benefit from public funding. But significant EU and country funding of 450mm R&D is not yet assured. With the current European debt crisis and emphasis on austerity, significant funding for semiconductor R&D may be limited. Furthermore, there remains significant debate over research priorities with many in the European semiconductor community, including leading European device makers, favoring R&D emphasis on “More than Moore” programs.

Opening up the qualifying process for 450mm high volume production tools to European consortia would seem to benefit 450mm device makers, tool makers and the overall industry move towards 450mm wafers. In addition to expanding the number of qualifying tools and public R&D funding sources, European consortia can be expected to link important process development efforts in 3-dimensional transistors, 3DIC and other areas with 450mm production requirements. Many of the current EEMI450 programs also feature unique approaches to metrology and material handling, adding an important “innovation” element to 450mm development efforts. At this stage of the 450mm transition, however, it is uncertain how likely G450C will move to open up their primary tool qualification role to organizations they may perceive as competitors. According to Lieher, “The same consolidation forces affecting device makers and suppliers are affecting R&D facilities. Specialization will need to be furthered so there is minimal overlap.”

ASML Begins 450mm Development

Another noteworthy discussion in the European 450mm session was ASML’s plans for large wafer lithography systems to support high volume 450mm production. ASML successfully negotiated billions of dollars in capital investment by Intel, TSMC and Samsung this summer to support accelerated development of extreme ultraviolet (EUV) systems for 450mm manufacturing. Until a 450mm EUV lithography system is developed, 450mm pilot line development will utilize nano imprint technology, a significant R&D limitation according to many observers.

In perhaps the first public discussion of the company’s 450mm plans, ASML’s Frank Bornebroek discussed the product strategy and technology challenges for 450mm EUV systems. He described how ASML will now simultaneously develop four tools on two platforms to accommodate 450mm production. He said the initial versions will provide 30 wafers per hour in 2016-2017, extended to 60 WPH for EUV in 2018-2019. For immersion systems, ASML is targeting 50 WPH in 2016 and high volume systems in 2018.

While the company is committed to the G450C schedule for high volume production, significant technical barriers will need to be overcome. “It’s not just a scale up, but significant overlay improvements will be required…overlay drives patterning” said Bornebroek. “The larger the wafer, the more difficult it will be to improve productivity. We will need to accelerate 3-times more mass at 2-times more accuracy.”

ASML is in process of hiring an additional 200 employees to meet the aggressive delivery goals. 450mm systems will require a “full base frame redesign” with major changes to chucks, mirror blocks, stages, tables and handlers, with adaptations to sensor and metrology systems. Bornebroek indicated that “450mm wafers will provide limited cost benefit for scanning systems.”