Silicon-FilmTM solar cells

The Silicon-Film^TM process is being employed to develop two new solar cell products. The first is on an accelerated path to large-scale manufacturing. A key element in that development is optimizing the specific geometry of both the Silicon-Film^TM sheet and the resulting solar cell. The decision is based on several factors including cost, engineering concerns, and marketing issues. Solar cell performance has been retained with increasing size. The results of testing have indicated that there is no limit to the width of sheet generated by this process. Significant advances in solar cell processing have been developed in order to fabricate devices of this size including diffusion and application of the anti-reflection coating. An advanced thin-silicon-based photovoltaic module product is being developed. A low-cost monolithic interconnected array is being integrated into a module that combines the design and process features of advanced light-trapped, thin-silicon solar cells. This advanced product consists of a low-cost substrate, a nominally 50 μm thick grown silicon layer with minority carrier diffusion lengths exceeding 100 μm, light trapping due to back-surface reflection, and back-surface passivation. The thin silicon layer enables high solar cell performance and can lead to a module conversion efficiency as high as 19%.