1:15 PM - 1:30 PM
[10p-N104-2] Limiting Factors of Open-Circuit Voltage for Heterojunction Rib-Si Solar Cells
Keywords:Silicon solar cell, heterojunction
We are developing a thin Rib-Si solar cell with the aim of improving the open circuit voltage Voc by using thin wafers. This time, we will show the current status of conversion efficiency of Rib-Si solar cells and discuss the limiting factors of Voc. N-Si was used for the substrate. An a-Si: H / a-SiOx: H stacked structure is used for the passivation of the interface. We are preparing Rib solar cells with a thickness of 50micron to 120micron, and a conversion efficiency of about 21% has been obtained. From the viewpoint of Voc, 730 mV is obtained. The factors that limit the open circuit voltage of heterojunction solar cells can be broadly divided into (1) bulk recombination, (2) interfacial recombination, (3) hole concentration in the p layer, and (4) edge effect peculiar to small area cells. In this talk, we discussed these Voc limiting factors from an experimental and theoretical point of view.