Silicon heterojunction (SHJ) solar cells with an interdigitated back-contact
(IBC) exhibit high conversion efficiencies of up to 25.6%. However, due to the
sophisticated back-side pattern of the doped layers and electrode structure
many processing and patterning steps are required. A simplification of the
patterning steps could ideally increase the yield and/or lower the production
costs. We propose a patterning approach for IBC SHJ solar cells free of any
photo-lithography with the help of laser-induced forward transfer (LIFT) of the
individual layer stacks to create the required back-contact pattern. The
concept has the potential to lower the number of processing steps significantly
while at the same time giving a large degree of freedom in the processing
conditions optimization of emitter and BSF since deposition of the
intrinsic/doped layers and processing of the wafer are all independent from
each other.Comment: 6 pages, 3 figures, 1 tabl