Application of ink jet technology on photovoltaic metallization

Computer-controlled ink-jet assisted metallization of the grid pattern of solar cells with metallo-organic decomposition (MOD) silver inks offers a maskless alternative method to conventional photolithographic thin-film technology and screen-printing technology. This method can provide low-cost, fine-resolution reduction in process complexity by direct ink-jet patterning, avoidance of degradation of p-n junctions by firing at low temperature (350 degrees C), and uniform line film on rough-surface solar cells (unpolished solar cells for low-cost purposes). The metallization process involves jet-printed metallo-organic inks, belt furnace firing, and thermal spiking. With titanium thin-film underlayer as an adhesion promoter and multilayer ink jet printing, solar cells of 8.08% average efficiency without AR coating can be obtained. This efficiency value is approximately equal to that of thin-film metallized solar cells of the same lot.<
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