The Study Of Plasmon Solar Cell Simulation

It was found that the light absorption of the solar cell could be controlled by the nano-structuresintegrated on its surface.The optimal absorption characteristics over a wide band can be obtained byoptimizing the nano-structures. The development of micro-nanofabrication technology made itpossible to construct the nano-structures. In this paper, the main researches contents as follows:1. Solar cell fundamental theory and numerical methodsThis paper revealed the working principle of solar cells, and the physical process of incidentillumination and the current generation. The four parameters was analyzed: the circuit current, theopen circuit voltage, the fill factor, the photoelectric conversion efficiency. They are important inmeasuring the characteristics of solar cell. The electro-magnetic theory of nano-structures is used tostudy the spectral characteristics of solar cells. Maxwell’s equations is used to describe the interactionbetween the incident sunlight and the nano-structures, and is discrete with thefinite-difference-time-domain (FDTD) method in Yee cell. Then the numerical methods areestablished.2. Enhancement absorption mechanism of a-Si:H thin film solar cellFDTD method is used to study the a-Si: H thin film solar cells, and analysis the factors of surfacespectral characteristics, such as the electrode, the back electrode, the intrinsic absorption layer. Thematerial property of nano-particles, the size and the nano-particles’ location have an effect on thespectral absorption characteristics. By analyzing different metal materials, we find that Alnano-particles has the greatest effect on the absorption. Meanwhile, the absorption of Alnano-particles themselves is relatively small. The size of the particle in the bottom ITO layer isdiscussed.We find that when the radius of Al particle is30nm, the absorption enhancement of300nm~800nm wavelength is greatest. The position of the nano-particles is also considered, we findout the deposited nano-particles on the up side of the cell has a great effect on the absorption of theshort wave, and the deposited nano-particles on the bottom of the cell has a great effect on theabsorption of the long wave. Therefore, the structure of deposited one metal nano-particles on up andbottom of the cell is proposed in this paper. The radius of Al particles deposited on at the bottom ofthe ITO layer is30nm, The radius of Al particles deposited on at the bottom of the a-Si layer is50nm.It is the best structure to makes absorption larger in wider band.3.Experimental study on the nanostructure of silicon solar cells The silver film on the surface of the silicon wafer was manufactured by sputtering. Agnano-particles was shaped on the wafer surface by annealing. The surface topography of themicrostructure was measured by SEM. The reflectance spectral was measured by the UV-visible-NIRspectrophotometer. We experimentally studied the absorption characteristics of Si plane with Agnano-particles. A significant reduction of reflectivity was found.