The Formation And Effect Of Gold Nanoparticles On The Surface Of Single Crystalline Silicon Solar Cells

The solar cells have got fast development in both research and industry fields with the increasingly severe energy problems. More and more new materials, new structures and new process technology emerged. Although the solar cells have broad prospects for development, the current solar cells are lacking of competitive advantage at the energy conversion compared to traditional energy. It is very important to reduce the production cost and enhance the efficiency of solar cells to make the solar cells widely used.It is an important approach to improve the efficiency of solar cells by reducing the optical loss part. More photons can be scattered into the interior of solar cells through surface modification. Surface texture and growth of reducing reflection membrane are general used for silicon solar cells on the market, which could be optimized to further improve the efficiency of solar cells by using trapping nanostructures. A layer of gold film was deposited on silicon surface by evaporation, and then it would turn into gold nanoparticles by rapid annealing, which is called thermal dewetting. This structure could couple the sunlight with the particles and form the surface plasmons, which could effectively reduce the reflection of sunlight.The gold film evolution on plane substrates by rapid thermal annealing was represented in the dissertation, and based on this, the gold dewetting on rough silicon solar cell surface was analyzed systematically. The mechanism study of the formation of gold nanoparticles through thermal annealing was investigated. The relationship between the morphology and the process conditions were discussed in details. We found that the optical characteristics of the gold nanoparticles could be controlled by the change of annealing conditions and different thickness of gold deposition through the optical test. The transition from homogeneous dewetting to spinodal dewetting was observed when the thicker gold film was annealed on the silicon solar cell surface. In addition, compared with the plane substrate, the micro structures on the surface of a silicon solar cell has a great influence on the dewetting process. It is found that at the top and bottom of the pyramid structure of silicon exists different performance through dynamic analysis. This phenomenon is advantageous to the study of solar cell with wide spectrum or full spectrum light structure.We compared the dip-cast method with the thermal dewetting, both methods are used to couple the nanoparticles to the surface of silicon solar cells and find that the latter one is better. The influence of thermal process on the solar cell itself and the nanoparticles is analysed and concluded that the gold nanoparticles on the surface can make the efficiency enhancement.