Research On The Synergistic Mechanism Of SnO₂/CuO Carrier Selection Layer On Crystalline Silicon Cells

Crystalline silicon solar photovoltaic market occupies a dominant position,the current efficiency of polysilicon production line for 16-18%,the PERC battery production line efficiency has reached 22%,amorphous silicon thin film silicon heterojunction?SHJ?solar cells currently laboratory high photoelectric conversion efficiency of 26.6%,but compared the efficiency of the limit theory for silicon?29.4%?,there is still a large gap.With the continuous improvement of wafer quality,the composite loss at the contact?the area between the metal and the photonic absorption layer?has an increasingly obvious influence on the efficiency,which is considered as the final obstacle to approaching the theoretical efficiency.How to overcome this obstacle and eliminate the compound loss at the contact can be solved by introducing carrier selective contact.In this paper,chemical water bath method?CBD?configuration,precursor solution by spin coating method in polysilicon and back surface deposition SnO₂ and selective contact layer CuO film as the carrier,through X-ray diffractometer?XRD?,field emission scanning electron microscope?FESEM?,ultraviolet-visible spectrophotometer?UV-Vis?and Jane life tester structure,morphology and optical properties of thin films and Jane characterizing the life.The quantum efficiency,dark current and photocurrent curves of the crystalline silicon battery were obtained through the solar cell IPCE test system and the photoelectric response?J-V?test system.In this study,SnO₂ and CuO were respectively used to modify the front and back sides of silicon wafers,and the effects of different precursor concentrations,annealing temperature and time on the minority lifetime were studied.By testing the photoelectric performance of SnO₂/Si composite battery,it is proved that SnO₂,as an electron selection layer,can block the holes on the front of the battery,so that the Ag electrode can absorb electrons more rapidly,accelerate the separation of the holes and electron pairs on the front,and reduce the composite loss on the front.It increases the absorption of infrared and visible light.Compared with the original wafer,the short-circuit current of the modified crystalline silicon battery was improved by 7.9%,and the photoelectric conversion efficiency was improved by 10.5%.Second use of CuO to modification of the back of the silicon wafer,by testing the photoelectric properties of Si/CuO composite battery,prove that the CuO as hole choose layer can make the battery on the back of the electronics will be blocked,improving the barrier height between silicon and Al electrodes,reduce the battery on the back of the minority carrier compound,and because the intervention of CuO hole selection,and make the crystal silicon cells are more likely to form ohm contact on the back.Compared with the original wafer,the open-circuit voltage and photoelectric conversion efficiency of the modified crystalline silicon battery are improved by 6.4%and 7.4%respectively.On this basis,SnO₂/Si/CuO composite solar cells were prepared.Low fe-sub composite and effective multi-sub transmission were realized through carrier selective contact,and the spectral absorption of the cells was improved and the series resistance was reduced.In the end,the photoelectric conversion efficiency increased by 13.7%compared with the original.