The Surface Of Crystalline Silicon Solar Cells Woven Structured Process

According to the mono-crystalline silicon structure,key technologies of mono-crystalline silicon cell have been studied in this thesis,which are the texturization,diffusion and coating SiNx:H etc. In this thesis, the texturization problem was made a key study. Surface texturing is one of the key techniques to improve the efficiency of silicon solar cell. The technique of monocrystalline texturing has not been widely used for an uniforming process in industry,it is different for different factories and laboratories. Some problems need to be solved, such as how to judge the quality of the texturing, and how to keep the stability in the industrial manufacture,etc.. In this paper, wet chemical etching on monycrystalline silicon wafer was investigated. The alkalic mixtures contain NaOH and additives.The concentration of the mixture affects the microcosmic formation,etching rate and the stability of the mixture. Even the tiny change of the alkalic mixtures,exactive temperature and exactive time would bring a diferent surface formation. So the parameters should be kept in an allowable range. In the industrial solar cell processing, the concentration will change when the alkali consumes. Adjusting the concentration of solution in time is the guarantee of texturing structure formation.The microcosmic formation afects directly the manufacture process of solar cell and the cell performance. The samples which have low reflectance present deep groove when the crystal lattice has defects and locates in the crystal boundary. This kind of groove takes disadvantage on cleaning, passivation and screen printing. The high reflectance samples have the smooth surface formation,but the light trapping is not idealized. How to make the balance between the light trapping and the electricity performance is a problem need to be solved. In this thesis, we have applied the texturisation method to the industry production, the suede surface was made in 125mm* 125mm mono-silicon chips.The short circuit can reach the value of 5.35 ampere and the solar cell efficiency can be achieved to 17.4%..