Straighforward in-line processing for a 16.8% efficient mc-Si solar cell

A simple in-line industrial process has been developed for commercial multicrystalline silicon (mc-Si) which results in solar cells with an average efficiency of 16.5%. The best cell has an efficiency of 16.8%. These are the highest efficiencies reported for full inline processing. The process consists of an acidic etch for texturing, homogeneous spin-on phosphorous and a belt furnace emitter diffusion, MicroWave PECVD for silicon nitride layers, and screen-printed metallization. The silicon nitride layer serves as antireflection coating and provides bulk and surface passivation. Detailed characterization and computer simulation showed that implementation of already proven technologies in the current cell processing could lead to efficiencies close to 18%.