There is a huge market today for solar energy driven products. In this area, there are innovations happening every day and which companies are complementing with the incorporation of newer age technologies. In this scenario, IMEC, the reputed research center for Nanoelectronics has just announced a path-breaking innovation in the field of silicon solar cells. They are using a processing sequence that is one of its kinds and is primarily based on laser doping technology. The new solar cells are of i-PERC type and with a larger area of 156 mm X 156 mm. The doping process involves the deposition of Al2O3 (Aluminum Oxide) on the solar cell surface to ensure a black surface.
The aluminum oxide coating is accompanied by a Nickel-Curium (NiCu) coating on the frontal side. This ensures that the efficiency of conversion is above 20 percent. In the past, the black surface creation required a firing process. However, with the new laser doping process, those requirements no longer exist. The NiCu plating provides for a metallization process which can be done at much lower temperatures. Earlier, due to the higher temperatures required, the Aluminum Oxide layer used to undergo a substantial amount of degradation, which is also eliminated now. The solar energy conversion efficiency is improved and increased, due to the decrease of the metal stack optical degradation.
The IMEC program director, Mr Jozef Szlufcik, had mentioned that the key factors that contribute to industrial growth are attaining simplicity in the processes and realizing that taking ownership comes with a cost. He had also added that the new technology will go a long way in reducing costs, and the silicon cell technology will flood the market with its cost-efficiency and better performance. The cost-of-ownership will also reduce drastically by using the i-PERC technology, and he maintains that this will be a milestone in the solar cell industry.
The new process, as envisaged and implemented by IMEC, is very simple, owing to the fact that the Aluminum Layer Deposit acts as the best doping source, and enhances the proper formation of the black layer (BSF). The complete process was trialed at IMEC, with great success. The 156mm X 156mm surface that was created from i-PERC silicon cells had efficiency above 20 percent. The contact quality was also of great quality, due to the fact that these silicon cells had high fill factor, even after the usage of anneals of low temperatures.
The implementation of the laser doping technique, as taken up by IMEC will help achieve high efficiency and cost effective cell structures. The solar cells of back contact type are examples of such technique implementation. Solar energy harnessing is the order of the day, and these companies who are using the cutting edge technologies to come out with great products are the ones to look out for. Not only will the general people and industries be benefitted, the environmental benefits are also large in number. The cost factor also reduces substantially, and as IMEC puts it – get more energy t lower costs.