Direct fabrication of cone array microstructure on monocrystalline silicon surface by femtosecond laser texturing

- A quasi uniform cone array like microstructure silicon surface had been successfully fabricated by direct femtosecond laser texturing and using perpendicular grooves texturing structure, and without any other optics.
- The relative reflectance of fabricated silicon surface has been reduced to less than 9% in the measured wavelength range from 400 to 1000 nm. The fabrication approach has overcome the disadvantage of excessively ablated points of intersection, which generally will affect the fabricated surface reflection in ordinary perpendicular microgroove fabrication approaches.
- In addition, the alternative fabrication method will be presented in detail.

Improving the utilization ratio of sunlight is a key factor for the development of solar cell. In this paper, a quasi uniform cone-array-like microstructure was directly fabricated on monocrystal silicon surface in atmosphere by using an alternative femtosecond laser texturing technique. The fabricated cone array like microstructure has a spike depth of up to 8 μm and is able to substantially reduce light reflection due to the effective optical coupling between the incident light with the cone array like microstructure. Compare to planar silicon wafer, the relative reflectance of the cone array structure has been decreased to less than 9% in the measured wavelength range from 400 to 1000 nm. This may be a promising method for the optimal fabrication of surface-microstructure photovoltaic material, such as solar cell, infrared sensor, etc.