Preparation method of silicon wafer micro-nano turbid transparent composite suede and application thereof

Abstract

The invention discloses a preparation method of a silicon wafer micro-nano turbid transparent composite suede. The method comprises the following steps: forming a micron-sized pitted surface layer onthe surface of a silicon wafer by sand blasting equipment; further manufacturing a nanoscale pitted surface layer on the surface of the micron-sized pitted surface layer, and finally forming a composite suede structure in which the nanoscale pitted surface layer is smooth and light-transmitting after complete turbidity removal and a low-reflection semitransparent turbidity layer is still reservedafter a micron-sized pitted surface layer etching process through an etching process. The technical process is simple, the depths of the micron-sized pitted surface layer and the nano pitted surface layer are stable and controllable, and the forming precision is high; according to the formed micro-nano turbid transparent composite structure, the light receiving area of the crystalline silicon of the solar cell is increased; the influence of the illumination angle is small, the received oblique light beams are large, weak sunlight of morning sunshine and sunset sunshine can be effectively responded, the manufactured solar cell piece can be horizontally placed, tiny nanoscale transparent shallow pits are quite beneficial to absorption of weak reflected light, and the utilization rate of theweak light of red oranges is comprehensively increased.

Description

technical field [0001] The invention relates to the field of solar cells, in particular to a preparation method and application of a micro-nano-turbid composite suede surface of a crystal silicon wafer. Background technique [0002] With the rise of energy consumption in developing countries, the existing fossil energy is gradually exhausted, and the search for renewable energy has become the consensus of all countries. Renewable energy includes solar energy, wind energy, water energy, etc. Among them, solar energy has attracted the attention of various countries because of its wide distribution and availability everywhere. [0003] The key issue in the development of solar cells is to increase conversion efficiency and reduce costs. For silicon-based solar cells, in 1997, Eric. Mazur et al. from Harvard University in the United States used femtosecond laser pulses to repeatedly irradiate the surface of silicon wafers in SF6 and Cl2 gas environments. A conical peak-like arr...

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Problems solved by technology

[0006] 2) Dry-process black silicon is greatly affected by equipment parameters, and the investment in hardware equipment is high;

[0007] 3) Wet black silicon is greatly affected by the quality of silicon wafers and process conditions

Specifically, the wet black silicon reaction process consumes a large amount of heavy metal Ag, leaving too many metal particles will increase the burden of subsequent cleaning work, and if the cleaning is not clean, the surface will become a carrier recombination center, and the efficiency of the cell will decrease.

[0008] However, whether it is laboratory technology or mass production technology, they are all pursuing to reduce the surface reflectance of silicon wafers. The current microstructure of the suede surface has high turbidity, opaque medium layer, too deep suede bottom, too high suede peak, etc. The bottom of the pit is too deep. Although the above microstructure successfully reduces the reflectivity, it also makes it difficult to absorb sunlight in an all-round way, short power generation time, and low photoelectric conversion efficiency. Moreover, the absorbed photogenerated carriers The recombination loss is large, and it is difficult to flow to the silver paste electrode; the peak or pyramid-shaped suede also causes the silicon wafer to consume a lot of material when preparing the suede, and it is difficult to continue to reduce the thickness; and the silicon wafer with the above structure is difficult to process and easy to break. The disadvantage is that the visible light of the rising sun or setting sun is difficult to illuminate the back or pit bottom of these suede structures. When the components are installed, they need to have an inclination angle to face the sun, but if the inclination angle is large, the wind pressure of the components is high, and they are easily destroyed by strong winds.

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