By Bettina Weiss, Sr. Director, SEMI PV Group

Based upon the experiences of other industries, technology developments in cell efficiency and increases in manufacturing economies of scale will not be enough to reach grid parity goals as fast as the world desires. The solar PV industry needs to look at meaningful cost reduction through a global, robust and well-organized supply chain. The current learning curve for the industry is not as steep as other electronic industries, especially semiconductors which use many of the same processes, materials, and suppliers as PV. A faster learning curve for the solar PV industry could be accomplished through better industry collaboration, including industry standards and technology roadmaps.

The progress made by semiconductors in cost reduction is one of the technological marvels of our time.  Since 1975, the cost of one transistor has been reduced by a factor of about 4,000,000.  This achievement has often been ascribed to Moore’s Law, the prediction that the number of transistors that can be placed inexpensively on an integrated circuit would double approximately every two years.  Learning curve cost reductions summarized by Moore’s Law has led to the dramatic market expansion of chips into nearly every facet of modern life, and many observers see it as a useful guide to cost reduction in the PV industry. While thin film and c-Si cells do not benefit from lithography-enabled feature-size reductions that comprise much of cost reductions in semiconductors, much of Moore’s Law is directly related to productivity, yield, and other cost reductions not related to feature-size reductions. Since PV manufacturing is based upon many of the same processes and materials as IC and display manufacturing, there remain important learnings from these industries that can be applied to solar cells and modules.

For over twenty years, keeping pace with Moore’s Law was accomplished by individual companies, working independently on common technical problems. For decades, the idea that a technology roadmap was semiconductors was necessary to sustain an acceptable rate of industry progress was simply not part of anyone’s expectation. It was not until the 1980’s—twenty years after Gordon’s Moore’s observation about the rate of improvement in semiconductors—that the first international roadmap for technology development was produced. Today, the industry-wide agreement to advance the industry as a common rate-- characterized by the International Technology Roadmap for Semiconductors (ITRS)--is recognized as a natural and necessary compass and integral component of the IC industry.

The ITRS document describes the technological targets required to achieve Moore’s Law over numerous areas from research design, to photolithography, materials, and other parameters.  It is updated annually and provides a technology forecast over a rolling 15-year timeline.  It has thousands of contributors and pages and is used by hundreds by companies in all regions of the world.  Many see the ITRS process as an effective way to identify and target key requirements and contend that “innovation is spurred by identifying requirements.”  The open and public process fosters a healthy “beat the roadmap” behavior by the industry.  Some see the PV industry as very much a “parallel universe” to semiconductors who can benefit from the experience of the ITRS.

There are both similarities and differences between the critical roadmap issues in chips and PV.  Both involve substrates, interconnects, absorber/efficiency, metrology, packaging, and test.  Both have common business drivers such as cost reduction, throughput, quality and reliability, and sustainability. Roadmaps can effectively identify technology gaps and serve as “learning tools for the industry.”  With more exposure of the critical technology gaps, more focused and cost effective innovation can occur.  PV is clearly different from chips, however, and does not have the powerful organizing paradigm of the next process node that helps ground the semiconductor roadmap.

Industry standards also have a close relationship to technology roadmaps, and many view them as a natural consequence of industry collaboration and roadmapping. It has been said that “roadmaps without standards don’t work.”  Roadmaps are the group view of the technology path over time. Standards are the tools the industry uses to identify the set of specifications that define industry requirements. In other words, standards define where the industry collaborates, and roadmaps establish where the industry competes. Several studies have identified billions of dollars in industry costs that the semiconductor industry has eliminated with standards.  Are there similar costs in the PV industry that can be reduced with a smart standards effort and gets us closer to grid parity?  Many believe there are. 

The PV industry is just starting to address roadmaps and standards.  Several manufacturing standards have already been adopted by the industry and there is a growing participation by key constituents in the standards development process.  Active PV standards committees are in place in North America, Europe, Japan, and Taiwan under the SEMI International Standards Program, the same platform and process that supports IC manufacturing standards.  One major standard specified how different machines or processes communicate together, a fundamental requirement for the modern automated factory and huge contributor to manufacturing efficiency.  The standards effort in PV appears to be well on its way to contributing to a steeper learning curve

Roadmaps are just now being considered by the industry.  A recent survey of cell and module manufacturers, equipment and material suppliers, and other key players ranked lack of industry roadmap and effective collaboration second behind government polices as a key barrier to industry growth.  However, some industry participants believe it is too early for a technology roadmap and that engaging in an open, public dialogue could be harmful. Collaboration opponents object that roadmaps cannot define industry growth in such a dynamic market environment.

Last month, SEMI PV Group announced the formation of the European Crystalline Cell Technology and Manufacturing Group (CTM). This special interest group of eight crystalline solar cell manufacturers (Q-Cells, Deutsche Cell, Bosch Solar Energy, Schott Solar, Sovello, Sunways, SolarWatt/Systaic Cells and Solland) is working together in a pre-competitive environment to address the technology challenges facing the photovoltaic industry. The CTM Group has begun work on a crystalline solar cell technology roadmap up to the year 2020. This particular roadmap describes the development of crystalline solar cell technology with focus on materials, manufacturing processes, and product development. As part of this activity, the priority of the CTM Group will be the definition of the development processes for raw materials, cell technology and cell manufacturing. The group also aims to optimize the interfaces within the entire manufacturing supply chain to help achieve this goal. How this European group leverages their roadmap activities to the global supply chain and connects with industry cluster efforts in other regions have yet to be determined.

Technology roadmaps and industry standards are complex issues for the industry to consider, involving fundamental issues of competition and cooperation.  Along with the CTM Group, discussions are underway between other key stakeholders around the world trying to identify areas where cooperation makes sense.  As these discussions continue, the industry has the opportunity to learn from the semiconductor industry and find its own path, to find its own Moore’s Law that drives down costs and accelerates grid parity, enabling a great solar era unsupported by government incentives.

For continuing dialog on industry collaboration, check out PV Group organized programs at Intersolar North America.

PV Group, The Grid – April 2010