| Abstract |
Silicon solar cell technology has greatly advanced in the last three decades--from merely concepts to a full-fledged industry. The performances of commercial cells and modules are now at levels that would have been very difficult to imagine just a few years back. At the same time, PV energy sales are expected reach 1 GW/yr in the near future, and there has been a rapid drop in the selling-price of PV modules. This is indeed astounding progress. However, this path has not been easy or free from obstacles and bottlenecks. There have been numerous difficulties and barriers in the science and technology of photovoltaics, as well as on the business end. For example, there have been times of insufficient funding, limited R&D resources for universities and laboratories, and a shortage of feedstock. Si-PV has overcome these hurdles and many other barriers. The PV industry has weaned itself away from the microelectronics technology, many new techniques of crystal growth and low-cost cell fabrication methods (suitable for PV) have been successfully applied, and mc-Si cells are nearing the efficiencies of CZ-Si wafers. On a more technical side, perhaps the most intriguing achievement is the development of the science and technology for making high-efficiency cells on low-quality material through gettering and impurity/defect passivation. Si-PV is continually on the path to lower costs and to be competitive with conventional sources of electric energy. Hopefully, this most significant barrier, of meeting the conventional energy cost, will be surmounted in the near future. |
