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Posted: Jan 27, 2011
Road Map for CIGS Solar Commercialization
(Nanowerk News) Sol Array, LLC is broadening its collaboration with China National Building Materials Group (CNBM), one of China's fortune 500 companies and top producer for building materials, to enhance its effort for CIGS commercialization. Sol Array has been working with CNBM as a co-developer and a minority partner, set up as the "Guang Dong Kai Sheng Photovoltaic Technology Research Institute Company Limited", and is headed by CEO/President of CNBM, Mr. Peng Shou. Sol Array believes that the partnership with CNBM will help expand China°'s current meager thin-film solar market and alter it into a major solar-user country, rather than merely the largest exporter of silicon solar modules. Such undertaking is fully in-line with China's current policies in the solar industry, whose primary mission is to alleviate the large and growing pollution problem of coal-fired power plants for China°'s environmental concerns.
The espoused process by the partnership aims specifically for volume production, and uses commercially available inexpensive soda-lime glass as substrate material. An automated and continuous in-line physical vapor deposition (PVD) process was adapted for the entire deposition of the thin-film stack, using a 4-element CIGS compound target for a simple, one-step deposition. This eliminates an extensive selenization process, and does away with the cumbersome co-evaporation of various CIGS elements for the formation of the active CIGS layer. Also, it ensures uniformity and repeatability in mass scale production, leading to a highly efficient and low cost manufacturing format.
Sol Array is now in discussions with CNBM on further collaborative efforts for their CIGS program. This includes exploring division of their corporate emphases by possibly entering into a sister company relationship, where CNBM°'s emphasis will be in CIGS module production, while Sol Array will be engaged in building CIGS production systems. The two companies further investigated the possibility of a 20MW CIGS module production line construction, to be housed in a newly established solar module production base, situated in San Shui, Guangdong, P.R.C., where facilities are nearing completion.
Jimin Ma, CEO/President of Sol Array LLC, has stressed that: "Of paramount importance for staying power, is the ultimate challenge of commercializing CIGS solar ®C a program of comprehensive cost reduction for system design, capital equipment, middle management, manufacturing and sales. This can come about from the synergy between Sol Array°'s strength in equipment design, automation and R&D, merging with CNBM°'s strength in large scale manufacturing."
This follows success by the co-development in achieving sputtered "stoichiometric" films from 4-element CIGS targets, where atomic proportions match that of industry's ideal composition, retaining almost identical composition in the CIGS film as in the target, with negligible selenium loss during deposition.
The proprietary process has just been proven successful, after months of difficulties dealing with frailty of the ceramic target due to its poor thermal conductivity, and in adapting pulsed dc in place of RF magnetron sputtering for speed considerations. Furthermore, an automated, pass-by in-line deposition approach is being adapted into the standard operating procedure. This is considered best for controllability and uniformity over large format glass substrate for volume production versus batch evaporation.
The approach also did away with large quantities post selenization, usually done by heating films of just the three metals in considerable amounts of toxic hydrogen selenide gas ®C a time consuming process that has been the industry norm. Instead, the patented process requires only a very small amount of solid selenium, used during annealing for crystal growth, merely to contain the selenium from escaping at the annealing stage, thus eliminating the problems of controlling and removing vast amounts of poisonous hydrogen selenide gas.
Although early results had shown good composition of the CIGS film, the packing density of crystals and their size needed further improvement; it is hoped that a technical paper on further findings will be published later this year.
Collaboration is also expected to continue with its existing target suppliers based in the USA. This includes the pressing powders of the four elements in CIGS as ceramic CIGS sputtering targets, having the highest possible packing density.
Sol Array has filed some 5 US patents relating to these new processes, and expects to demonstrate the methods in the new facility this year, showing their relevance to viable production. For more information contact Jimin Ma, E: jma[.]solarrayllc.com
CNBM (Beijing, P.R.C., cnbm.com.cn) is in the top 500 Chinese companies, with revenue of over $100 billion US. It is a China State Owned Enterprises conglomerate, engaged in building material manufacturing, with new focus in the synergy between CNBM's building material forte and the "building integrated photovoltaic (BIPV)" solar industry. CNBM was listed on the Hong Kong Stock Exchange on 23 March, 2006 and joined the Hang Seng China Enterprises Index on 10 March, 2008. It currently has a staff count of 50, 000, with fixed assets of £§55 billion RMB ($US 8.25 billion); it owns 200 subordinates of solely owned and joint-venture companies, 6 among them were publicly listed companies where CNBM has a controlling shares percentage.
CNBM is currently the largest glass manufacturing plant producer, with good ties to China's policy makers. It has 20 production lines of modern float glass with annual production of over 40 million weight cases of high-quality float glass in various colors and specifications. It produces 16 million pieces of ITO conductive film glasses, and is China°'s only glass enterprise equipped with production capacity of ultra thin and ultra thick glass with range from 0.55mm to 25mm. Also, in terms of production capacity, CNBM is currently the largest cement, gypsum board and glass fiber producer in Asia.
About Sol Array, LLC
SOL ARRAY, LLC (solarrayllc.com) is an entrepreneurial US company, incorporated in Delaware, and it has an office at 50 Francisco St., Ste. 120, San Francisco, CA 94133, USA. It aims to participate in the commercialization of thin-film CIGS solar industry and believes that the core collaborative synergy lies in: technology exchange, corporate learning and market positioning, where its affiliations can leverage and amplify the core competencies of each participant, in areas of manufacturing, recruiting, process technology, marketing, research and development; where global competitiveness is pivoted on the proper balance of research, production and marketing, that fuses the synergistic forces for long term endurance. For product improvements, it has a network of technology talents, based in the US and other European research institutions for product development; where the company's forte is in system design for in-line sputtering line and turn-key operations worldwide.