No abstract

No abstract

International audienceThis work deals with the understanding of the transport behavior of different deposited Indium Tin Oxide (ITO) layers on the emitter of n-type heterojunction solar cells. A complete study based on effective lifetime measurements has been carried out on samples with different ITO thicknesses to evaluate the passivation quality before and after ITO deposition, showing that increasing the ITO thickness degrades the passivation properties only at low injection level. Further characterizations coupled with numerical simulations demonstrate that such a behavior is due to recombination at the ITO/(p) a-Si:H interface induced by the ITO layer

Front electron collectors in rear emitter hydrogenated amorphous silicon/crystalline silicon (a-Si:H/c-Si) solar cells are comprehensively investigated with the objective of increasing cell power conversion efficiency. Since such cells benefit from the lateral electron conductivity of the n-doped substrate, the electrical constraint on the front transparent conductive oxide (TCO) layer is relaxed. However, cell improvement is only expected if the front side is optimized. Here, we present our understanding of recombination losses in the front amorphous silicon layers and at the a-Si:H/c-Si interface, which determine the short-circuit current. In addition, we show how the TCO/(n + i)a-Si:H/(n)c-Si contact has to be finely engineered to minimize the resistance for electrons to be extracted. Both points are addressed through experimental and simulation works.