- Details
- Last Updated: Friday, 30 December 2022 15:10
Low Reflectance silicon wafers
Goal: Develop a process that generates Low Reflectance silicon material for Photovoltaics and Optoelectronics
Nitrogen doped Czochralski (N-Cz) silicon wafers heat treated and etched chemically produced textured surfaces that efficiently trap light. N-Cz samples exhibited, over a wide spectral range, a very low effective reflectance, compared to other Cz samples.
[111] oriented silicon, when etched with NaOH at 80C produces texture at the material surface.
N doped silicon heat treated develop oxynitride nanofeatures (precipitates and voids covered with nanometer thick oxynitride layer) in the near surface region. When etched these leave a finely textured surface that causes the observed extremely low reflectance.
Only a small amount of light escapes from the bulk and forms a boundary layer of diffuse light, and which couples with the textured surface.
N doped silicon processed to produce extremely fine nanostructure at the surface that results in low reflectance.
This work was sponsored by NREL and the former photovoltaic company Astropower/GE. The process was integrated in Astropower solar cell production line.