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Both structured wire and diamond (or fixed abrasive) sawing wire have been put forward as solutions for further increasing the productivity of the multi wire sawing process for PV applications.While structured wire relies on improvement of slurry drag into the sawing channel,diamond wire results in a fundamentally different cutting mode.Starting from an evaluation of cutting efficiency,we introduce the energy spent per wafer formed (Ew)as a non-biased parameter taking into account differences in kerf loss.We observed improvements of Ew versus standard (straight) loose abrasive sawing wire ranging from approximately 13% to 67% for structured and optimised diamond wire respectively.Secondly,we found that the mode of improvement is also different: for structured wire,we confirm an improved material removal rate while the required power remains constant.On the other hand,for diamond wire,we have been able,through wire and process optimisation,to not only further increase the material removal rate,but also substantially decrease the required cutting power.In a second part of the study,we have assessed the impact of the different Ew values on the main wafer characteristics.We found that structured wire does not affect the wafer strength of as-cut wafers,while for fixed abrasive sawing wire a strong orientation dependency of strength is noticed with variations of-30% to 40% for parallel and perpendicular loading,respectively.Compared to straight wire,total thickness variation values obtained were slightly lower for structured and much lower for diamond wire cut wafers.