Light trapping structures for silicon solar cells via inkjet printing

Inverted pyramids and v‐groove texturing has been employed for high efficiency cells because they provide advantages over the conventional upright random pyramid texturing used industrially. This letter reports the use of an inkjet‐patterning technique as an alternative to the expensive and complex photolithography method normally used for the dielectric patterning step required for the fabrication of these light trapping structures. The resulting single‐sided and double‐sided inkjet‐patterned textures are equivalent in structure to matching textures produced using photolithography and they show enhanced cell absorption over random upright pyramid texturing in the near‐bandgap wavelength range. Photocurrent calculations show that the inkjet‐patterning approach is a promising direction for current commercial wafers of about 200 μm thickness although future inkjet technology improvements will need to reduce pattern feature dimensions to reduce the extent of silicon etching for compatibility with the predicted thinner wafers in the future. SEM micrograph of inkjet fabricated tiled inverted pyramids.