Investigation Of Silicon-based Nanowire Heterojunction Solar Cell With Self-assembly Mask

Due to the rapid growth of the world's population and the improvement of living standards,the rapid increase in demand for energy has made the problems of the energy crisis and environmental pollution more and more acute.With the increasing depletion of fossil energy and the deterioration of the global environment,clean energy such as solar energy has attracted more and more attention.One of the main methods of solar power is photovoltaic power.In addition to the impact of climate issues,the main reason that restricts the widespread use of photovoltaic power generation is the relatively high battery prices.Silicon materials are abundant and non-toxic,and they are the main raw materials for photovoltaic cells.However,the cost of crystalline silicon used in photovoltaic cells is relatively high.Therefore,many businesses try to reduce the thickness of the silicon wafer as much as possible to reduce costs,which will directly affect the efficiency of photovoltaic cells.Aiming at the problems of high cost and low conversion efficiency ofphotovoltaic cells,this paper proposes a new type of nanowire battery.The specific research content is as follows:(1)Research on China's photovoltaic installations this year.At present,China's total photovoltaic installations rank first in the world.Research status and prospects of photovoltaic nanowire cells and photovoltaic heterojunction cells.The conversion efficiency of current heterojunction planar cells can reach 26.6%.(2)Analyze the reasons that will affect the conversion efficiency of photovoltaic cells,light loss,series-parallel resistance,and carrier recombination.The optical loss can be reduced by adding an anti-reflection layer,the resistance of the series resistance can be controlled by adjusting the thickness of the intrinsic layer,and the carrier recombination phenomenon can be reduced by a passivation process.(3)Simulate and analyze the absorption of sunlight by different materials.Combining narrow bandwidth crystalline silicon(c-Si)materials with wide bandwidth amorphous silicon materials can theoretically achieve higher open circuit voltage.The silicon substrate with and without the light trapping structure is calibrated under various parameters by simulation analysis.As a result,the battery with the light trapping structure combined performs better in all aspects.Therefore,combining the advantages of heterojunction batteries and nanowire batteries,a new type of nanowire heterojunction battery is proposed,which has both the higher open circuit voltage of the heterojunction battery and the good The advantages of electronic transmission channels and traps.(4)Design the preparation process and prepare the samples,in which the technology of preparing nanowires uses microparticle self-assembly technology instead of traditional mask making.The diameter of nanowires can be controlled by controlling the particle size,which greatly reduces the cost.A nanowire array with a maximum height of m2.7m and an average height of m0.7m was prepared,which has good light absorption.(5)The battery parameters are calibrated,and the optimal battery efficiency is measured as 2.71%.The efficiency of the nanowire heterojunction battery prepared in the experiment is still relatively low.The causes of low battery efficiency are analyzed,including factors such as light energy loss,intrinsic layer thickness,defect state,and series and parallel resistance.