Monocrystalline Silicon Texture And Study On Ceramic Roller Type Diffusion Boron Emitter

The technology of making and diffusing is the basic technology of solar cell preparation.The surface of crystal silicon can reduce the reflectivity of light and increase the effect of light trapping.However,the PN junction formed by diffusion is the core of solar cells.At present,there is a mature technology for making single crystal silicon wafers,and the pyramidal suede structure is usually formed by etching the anisotropic alkali solution of monocrystalline silicon.Isopropanol is usually added as surfactant in alkali solution,but the linear mark on the surface of single crystal silicon wafer is difficult to be removed by using traditional fluting liquid and additives,and it is difficult to achieve the ideal fine uniform and dense pyramid structure.In this paper,the ideal fine,uniform and compact pyramidal flannelette structure of about 2 μm is obtained by searching for high quality additive of non-alcohol fluting.Meanwhile,the process of making single crystal silicon wafer and polished single crystal silicon wafer by wire cutting is discussed.It is found that polished silicon wafers undergo four stages of nucleation,growth,forming and homogenization in the case of alkali corrosion of the additive for making pile,while wire cut silicon wafers have long pyramids in the severely damaged area of crystal lattice(broken and broken pits).The corrosion process of silicon wafer consists of four stages: line mark removal,line mark residue,molding and homogenization.In the current photovoltaic market,most manufacturers of crystalline silicon solar cells use boron doped P-type silicon wafers to produce the cells,while phosphorus doped N-type cells are becoming more and more popular for their unique advantages.The boron emitter of N-type battery is usually prepared by the diffusion of boron tribromide in the tube furnace,and the gas fluidity during the tube diffusion is easy to affect the uniformity of the diffusion,and the heat diffusion mode of the tube furnace has a high cost.Some foreign research institutions have developed a horizontal chain diffusion mode,which is low in cost,basically phosphorus diffusion forms N emitter,but the chain diffusion conveys silicon wafers using stainless steel wire mesh.It is easy to pollute the battery and affect the efficiency of the battery.In this paper,a kind of atomizing device is developed to prepare uniform boron emitter by using the low cost boric acid diffusion source in the roller diffusion furnace of ceramic roller shaft.The diffused square resistor ranges from 40 to 110 and the cell efficiency of uncoated cells reaches 10%.